SECTION 6C1-2A - DIAGNOSTIC TABLES –

V6 ENGINE

IMPORTANT

Before performing any Service Operation or other procedure described in this Section, refer to Section 00

CAUTIONS AND NOTES for correct workshop practices with regard to safety and/or property damage.

CONTENTS

SYSTEM COMPONENT LOCATIONS

PCM WIRING DIAGRAMS

POWERTRAIN CONTROL MODULE CONNECTOR

IDENTIFICATION

PCM CONNECTOR TERMINAL VOLTAGES WITH

EXPLANATIONS

PCM ENGINE AND TRANSMISSION DIAGNOSTIC

TROUBLE CODES (DTC)

4L60-E TRANSMISSION FLUID CHECKING

PROCEDURE

TABLE A V6 PCM - ON BOARD DIAGNOSTIC (OBD)

SYSTEM CHECK

TABLE A-1 V6 PCM - NO CHECK POWERTRAIN

MALFUNCTION INDICATOR LAMP (MIL)

TABLE A-2 V6 PCM - NO SERIAL DATA

TABLE A-3.1 V6 PCM - ENGINE CRANKS BUT WILL

NOT RUN

TABLE A-3.2 V6 PCM - ENGINE CRANKS BUT WILL

NOT RUN

TABLE A-3.3 V6 PCM - ENGINE CRANKS BUT WILL

NOT RUN

TABLE A-4.0 V6 PCM - STARTER CRANKING

CIRCUIT

TABLE A-4.1 V6 PCM - FUEL PUMP ELECTRICAL

CIRCUIT

TABLE A-4.2 V6 PCM - FUEL PUMP ELECTRICAL

CIRCUIT

TABLE A-4.3 V6 PCM - FUEL DELIVERY SYSTEM

TABLE A-4.4 V6 PCM - FUEL DELIVERY SYSTEM

TABLE A-4.5 V6 PCM - FUEL DELIVERY SYSTEM

TABLE A-6.0 V6 PCM - BAROMETRIC PRESSURE

SENSOR OUTPUT CHECK

TABLE A-6.1 V6 PCM - MAF SENSOR OUTPUT

CHECK

TABLE A-6.2 V6 PCM - TP SENSOR OUTPUT CHECK

TABLE A-6.3 V6 PCM - OXYGEN SENSOR CHECK

TABLE A-6.4 V6 PCM - CANISTER PURGE SOLENOID

CHECK

TABLE A-6.5 V6 PCM - ENGINE CONTROL EFI RELAY

DIAGNOSIS

TABLE A-7.1 V6 PCM - IDLE AIR CONTROL (IAC)

SYSTEM

TABLE A-7.2 V6 PCM - IDLE AIR CONTROL (IAC)

SYSTEM

TABLE A-8.1 V6 PCM - DIRECT IGNITION SYSTEM

(DIS) CHECK

TABLE A-8.2 V6 PCM - DIRECT IGNITION SYSTEM

(DIS) CHECK

TABLE A-11.1 V6 PCM - A/C CLUTCH CONTROL

(NON-OCC SYSTEM)

TABLE A-11.2 V6 PCM - A/C CLUTCH CONTROL

WITH OCCUPANT CLIMATE CONTROL (OCC)

TABLE A-12.1 V6 PCM - ELECTRIC FAN CONTROL -

STANDARD FAN PACKAGE

TABLE A-12.2 V6 PCM - ELECTRIC FAN CONTROL -

STANDARD FAN PACKAGE

TABLE A-12.3 V6 PCM - ELECTRIC FAN CONTROL -

HIGH PERFORMANCE FAN PACKAGE

TABLE A-12.4 V6 PCM - ELECTRIC FAN CONTROL -

HIGH PERFORMANCE FAN PACKAGE

TABLE A-12.5 V6 PCM - ELECTRIC FAN CONTROL -

HIGH PERFORMANCE FAN PACKAGE

TABLE A-13 V6 PCM - RESTRICTED EXHAUST

CHECK

DTC P0101 - V6 PCM MASS AIR FLOW SENSOR OUT

OF RANGE

DTC P0107 - V6 PCM BAROMETRIC PRESSURE

SENSOR SIGNAL VOLTAGE LOW

DTC P0108 - V6 PCM BAROMETRIC PRESSURE

SENSOR SIGNAL VOLTAGE HIGH

DTC P0111 - V6 PCM INTAKE AIR TEMPERATURE

SIGNAL VOLTAGE UNSTABLE

DTC P0112 - V6 PCM INTAKE AIR TEMPERATURE

SIGNAL VOLTAGE LOW

DTC P0113 - V6 PCM INTAKE AIR TEMPERATURE

SIGNAL VOLTAGE HIGH

DTC P0117 - V6 PCM ENGINE COOLANT

TEMPERATURE SIGNAL VOLTAGE LOW

DTC P0118 - V6 PCM ENGINE COOLANT

TEMPERATURE SIGNAL VOLTAGE HIGH

DTC P0121 - V6 PCM THROTTLE POSITION SENSOR

STUCK

DTC P0122 - V6 PCM THROTTLE POSITION SENSOR

VOLTAGE LOW

DTC P0123 - V6 PCM THROTTLE POSITION SENSOR

VOLTAGE HIGH

DTC P0131 - V6 PCM RIGHT HAND OXYGEN SENSOR

VOLTAGE LOW

DTC P0132 - V6 PCM RIGHT HAND OXYGEN SENSOR

VOLTAGE HIGH

DTC P0134 - V6 PCM NO RIGHT HAND OXYGEN

SENSOR SIGNAL

DTC P0151 - V6 PCM LEFT HAND OXYGEN SENSOR

SIGNAL VOLTAGE LOW

DTC P0152 - V6 PCM LEFT HAND OXYGEN SENSOR

SIGNAL VOLTAGE HIGH

DTC P0154 - V6 PCM NO LEFT HAND OXYGEN

SENSOR SIGNAL

DTC P0170 - V6 PCM LONG TERM FUEL TRIM (LTFT)

DELTA HIGH

DTC P0173 - V6 PCM SHORT TERM FUEL TRIM (STFT)

DELTA HIGH

DTC P0200 - V6 PCM INJECTOR VOLTAGE MONITOR

FAULT

DTC P0218 - V6 PCM TRANSMISSION FLUID

OVERTEMPERATURE

DTC P0325 - V6 PCM DSNEF SYSTEM FAULT

DTC P0327 - V6 PCM LEFT HAND KNOCK SENSOR

CIRCUIT FAULT

DTC P0332 - V6 PCM RIGHT HAND KNOCK SENSOR

CIRCUIT FAULT

DTC P0341 - V6 PCM CAM/CRANK SENSOR SIGNAL

INTERMITTENT

DTC P0342 - V6 PCM CAMSHAFT POSITION SENSOR

SIGNAL MISSING

DTC P0374 - V6 PCM 18X REFERENCE SIGNAL

MISSING

DTC P0400 - V6 PCM EGR FLOW FAULT INDICATED

DTC P0405 - V6 PCM EGR POSITION FAULT

DTC P0446 - V6 PCM CANISTER PURGE CIRCUIT

FAULT

DTC P0502 - V6 PCM NO VEHICLE SPEED SIGNAL

DTC P0503 - V6 PCM VEHICLE SPEED SENSOR

INTERMITTENT SIGNAL

DTC P0506 - V6 PCM IDLE SPEED ERROR

DTC P0507 - V6 PCM VACUUM LEAK

DTC P0530 - V6 PCM A/C PRESSURE SENSOR

CIRCUIT FAULT

DTC P0560 - V6 PCM SYSTEM VOLTAGE TOO HIGH

(LONG TIME)

DTC P0561 - V6 PCM SYSTEM VOLTAGE UNSTABLE

DTC P0562 - V6 PCM SYSTEM VOLTAGE LOW

DTC P0563 - V6 PCM SYSTEM VOLTAGE TOO HIGH

DTC P0601 - V6 PCM POWERTRAIN CONTROL

MODULE MEMORY

DTC P0712 - V6 PCM TFT SIGNAL VOLTAGE LOW

DTC P0713 - V6 PCM TFT SIGNAL VOLTAGE HIGH

DTC P0730 - V6 PCM 2-3 SHIFT SOLENOID B CIRCUIT

VOLTAGE HIGH

DTC P0740 - V6 PCM TCC ENABLE SOLENOID

CIRCUIT FAULT

DTC P0741 - V6 PCM TCC SYSTEM STUCK ON

DTC P0748 - V6 PCM PC SOLENOID CURRENT

ERROR

DTC P0753 - V6 PCM 1-2 SHIFT SOLENOID A CIRCUIT

VOLTAGE HIGH

DTC P0756 - V6 PCM 1-2 SHIFT SOLENOID A CIRCUIT

VOLTAGE LOW

DTC P0757 - V6 PCM 2-3 SHIFT SOLENOID B CIRCUIT

VOLTAGE LOW

DTC P0785 - V6 PCM 3-2 DOWNSHIFT CONTROL

SOLENOID CIRCUIT FAULT

DTC P1064 - V6 PCM LOW SPEED FAN - NO BCM

RESPONSE

DTC P1116 - V6 PCM ENGINE COOLANT

TEMPERATURE SIGNAL VOLTAGE UNSTABLE

DTC P1255 - V6 PCM THEFT DETERRENT SIGNAL

MISSING

DTC P1351 - V6 PCM IGNITION ELECTRONIC SPARK

TIMING (EST) CIRCUIT FAULT

DTC P1361 - V6 PCM IGNITION BYPASS CIRCUIT

FAULT

DTC P1372 - V6 PCM NO REFERENCE PULSES

WHILE CRANKING

DTC P1571 - V6 PCM REQUESTED TORQUE OUT OF

RANGE

DTC P1627 - V6 PCM PCM – ANALOG TO DIGITAL

(A/D) CONVERSION ERROR

DTC P1628 - V6 PCM PCM ERROR – ENGINE

COOLANT TEMPERATURE

DTC P1642 - V6 PCM LPG ENABLE SIGNAL OUT OF

RANGE

DTC P1643 - V6 PCM LPG FCV PWM OUT OF RANGE

DTC P1810 - V6 PCM TFP MANUAL VALVE POSITION

SWITCH ASSEMBLY CIRCUIT MALFUNCTION.

DTC P1860 - V6 PCM TCC PWM SOLENOID FAULT

DTC P1870 - V6 PCM TRANSMISSION SLIPPING

SYSTEM COMPONENT LOCATIONS

Figure 6C1-2A-1 Component Locations

Legend

1. Fuel Pump (Inside Fuel Tank)

2. Fuel Tank

3. OCC In –Car Air Temperature Sensor

4. Fuel Pressure Regulator

5. Exhaust Gas Oxygen (O2S) Sensor (Two)

6. Engine Harness (PCM) Ground (Two Terminals)

7. Idle Air Control (IAC) Valve

8. Throttle Position (TP) Sensor

9. Mass Air Flow (MAF) Sensor

10. Tachometer Lead

11. Powertrain Control Module (PCM) (Inside Vehicle)

12. Intake Air Temperature (IAT) Sensor

13. Fuel Injectors

14. Ignition Coils

15. Engine Coolant Temperature (ECT) Sensor

16. DIS Module

17. Air Cleaner

18. Crankshaft Position (CKP) Sensor

19. A/C Refrigerant Pressure Sensor

20. A/C Accumulator

21. Engine Cooling Fans (Two)

22. Oil Pressure Switch

23. Camshaft Position (CMP) Sensor

24. Battery

25. Engine Compartment Fuses

26. Engine Compartment Relays

27. Engine Compartment Fuse/Relay Centre

28. Engine Harness (PCM) Ground (Two Terminals)

29. ABS or ABS/TCS Hydraulic Modulator

30. Detonation Knock Sensors (KS) (Two)

31. Brake Hydraulic Failure Switch

32. EVAP Canister Purge Solenoid

33. Diagnostic Link Connector (DLC)

34. BCM

35. Vehicle Speed Sensor (VSS)

36. Check Powertrain MIL

Figure 6C1-2A-2 – Engine Compartment Fuse/Relay/Fusible Link Locations

Legend

Fuses

1. Fuel Pump Fuse – F28

2. Engine / BCM / Telematics– F29

3. RH Headlamps – F30

4. LH Headlamps – F31

5. Automatic Transmissi on – F32

6. Engine Sensors – F33

7. Injectors / Ignition – F34

8. Injectors / Ignition – F35

Relays

9. Start – R1

10. Blower Fan – R2

11. Headlamp (High Beam) – R3

12. Engine Control (EFI) – R4

13. Engine Cooling Fan Relay 2 – R5

14. Horn – R8

15. A/C Compressor – R11

16. Fog Lamp – R10

17. Fuel Pump – R16

18. Headlamp (Low Beam) – R14

19. Engine Cooling Fan Relay 1– R7

Fusible Links

20. Engine Cooling Small Fan F107 (30A)

21. Blower Fan – F106 (60A)

22. Main – F105 (60A)

23. Engine – F104 (60A)

24. A.B.S. – F103 (60A)

25. Lighting – F102 (60A)

26. Engine Cooling Large Fan F101 (30A)

Figure 6C1-2A-3 Engine Component Locations

Legend

1. Idle Air Control (IAC) Valve

2. Throttle Position (TP) Sensor

3. EGR Valve

4. Injectors

5. Direct Ignition System Module

6. L.H. Knock Sensor (KS)

7. Crankshaft Position (CKP) Sensor

8. Oil Pressure Switch

9. Camshaft Position (CMP) Sensor

10. Ignition Coils (Three Places)

11. Engine Coolant Temperature (ECT) Sensor

Figure 6C1-2A-4 Engine Component Locations

Legend

1. Fuel Pressure Regulator.

2. Canister Purge Solenoid.

3. Injectors.

4. R.H. Exhaust Gas Oxygen (O2S) Sensor.

5. Transmission Pass-Through Connector.

6. Vehicle Speed Sensor (VSS) (Automatic Trans).

7. PCM Connectors.

8. Engine Harness Ground.

Figure 6C1-2A-5 Engine Component Locations

Legend

1. Engine Harness Ground.

2. Ignition Coils (Three Places).

3. Direct Ignition System Module.

4. Camshaft Position (CMP) Sensor.

5. Oil Pressure Switch.

6. R.H. Knock Sensor (KS).

7. Vehicle Speed Sensor (VSS) Automatic Trans.

8. Injectors.

Figure 6C1-2A-6 Automatic Transmission Internal Electronic Component Locations

Legend

1. Vehicle Speed Sensor.

2. 1-2 Shift Solenoid A and 2-3 Shift Solenoid B.

3. Automatic Transmission Fluid Pressure (TFP) Manual Valve Position Switch.

4. 3-2 Downshift Shift Control Solenoid.

5. Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid Valve.

6. Torque Converter Clutch (TCC) Solenoid Valve.

7. Pressure Control Solenoid (PCS) Valve.

PCM WIRING DIAGRAMS

Figure 6C1-2A-7 PCM Wiring Diagram (1 of 10)

Figure 6C1-2A-8 PCM Wiring Diagram (2 of 10)

Figure 6C1-2A-9 PCM Wiring Diagram (3 of 10)

Figure 6C1-2A-10 PCM Wiring Diagram (4 of 10)

Figure 6C1-2A-11 PCM Wiring Diagram (5 of 10)

Figure 6C1-2A-12 PCM Wiring Diagram (6 of 10)

Figure 6C1-2A-13 PCM Wiring Diagram (7 of 10)

Figure 6C1-2A-14 PCM Wiring Diagram (8 of 10)

Figure 6C1-2A-15 PCM Wiring Diagram (9 of 10)

Figure 6C1-2A-16 PCM Wiring Diagram (10 of 10)

POWERTRAIN CONTROL MODULE CONNECTOR IDENTIFICATION

This powertrain control module voltage table is for use with a Digital Multimeter (DMM) to further aid in

diagnosis . Conn ect the B lack (-) probe to a goo d chass is ground, a nd back probe the powert rain c ontrol m odule

term inal with the Re d (+) probe. These v olt ages were der i ved f rom a k nown g ood ve hicle. T he vo lt ages you get

may vary due to low battery charge or other reasons, but they should be very close.

THE FOLLOWING CONDITIONS MUST BE MET BEFORE TESTING:

• Engine and Transmission at operating temperature

• Closed Loop

• Engine idling ( for “Engine Run” column)

• TECH 2 not installed

• Accessories “OFF”

BACKPROBING VIEW OF BROWN PCM CONNECTOR X1

Figure 6C1-2A-17 PCM Connector Terminal End View (1 of 3)

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

A1 3-2 CONTROL

SOLENOID 898 GN/WH 12 * B1 1-2 SHIFT

SOLENOID A

CONTROL

1222 L-GN 12 *

A2 2-3 SHIFT

SOLENOID B

CONTROL

1223 YE/BK 12 * B2 NOT USED - - - -

A3 LPG ENABLE

OUTPUT (LPG ONLY) 2531 WH/GN (1) (1) B3 EST OUTPUT 423 WH 0 2.0

A4 NOT USED - - - -

B4 BYPASS

CONTROL 424 TN/BK 0 4.7

A5 SYSTE M GROUND 450 BK/RD * * B5 SYSTE M GROUND 2753 BK * *

A6 NOT USED - - - -

B6 CAMSHAFT

POSITION

SENSOR SIGNAL

630 BK 4.8 4.4

A7 MAF SENSOR

INPUT 492 BN/WH 4.8 4.2 B7 CRANKSHAFT 18X

SIGNAL 647 L-BU/BK 5

2.7

3.0

A8 START RELAY

CONTROL 434 GY * *

B8 TORQUE

REQUEST 463 OG 0.2 0.2

A9 AIR

CONDITIONING

RELAY CONTROL

459 L-GN/BK 12 (2) B9 CRANKSHAFT

REFERENCE HIGH 430 PU 4.8 2-3

A10 CANISTER PURGE

SOLENOID 428 GN/YE 12 13 B10 CRANKSHAFT

REFERENCE LOW 453 BK/RD * *

A11 TCC SOLENOID

PWM CONTROL 418 BN 12 13

B11 TORQUE

ACHIEVED 464 BK/WH .9 3-6

A12 TCC ENABLE

SOLENOID

CONTROL

422 GY/RD 12 13 B12 ENGINE COOLING

FAN RELAY HIGH

SPEED CONTROL

473 BU/WH 12 (7)

Normal

Volta

es Normal

Volta

This powertrain control module voltage table is for use with a Digital Multimeter (DMM) to further aid in diagnosis. Connect

the Black (-) probe to a good chassis ground, and backprobe the powertrain control module terminal with the Red (+) probe.

These voltages were derived from a known good vehicle. The voltages you get may vary due to low battery charge or other

reasons, but they should be very close.

THE FOLLOWING CONDITIONS MUST BE MET BEFORE TESTING:

• Engine and Transmission at operating temperature

• Closed Loop

• Engine idling ( for “Engine Run” column)

• TECH 2 not installed

• Accessories “OFF” BACKPROBING VIEW OF BROWN PCM CONNECTOR X2

Figure 6C1-2A-18 PCM Connector Terminal End View (2 of 3)

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

C1 VEHICLE SPEED

OUTPUT TO

SPEEDOMETER

5197 PU/WH 0.1

0.1

D1 VEHICLE SPEED

SENSOR SIGNAL

1230 BU/WH * *

C2 IAC COIL “B” LOW 444 L-GN/BK NOT USE-

ABLE D2 VEHICLE SPEED

SENSOR SIGNAL

1231 TN * *

C3 IAC COIL “A” LOW 1748 L-BU/BK NOT USE-

ABLE D3 LH OXYGEN

SENSOR GROUND 1664 BU/BK * *

C4 IAC COIL “A” HIGH 1747 L-BU NOT USE -

ABLE D4 LH OXYGEN

SENSOR SIGNAL 1665 PU 450

Mv (4)

C5 IAC COIL “B” HIGH 1749 L-GN/WH NOT USE-

ABLE D5 RH OXYGEN

SENSOR GROUND 1667 GY/BK * *

C6 ECT/TP A/C

PRESSURE

SENSOR GROUND

2752 BK/YE * * D6 PCM GROUND 450 BK/RD * *

C7 TP SENSOR

SIGNAL 411 BU (5) (5) D7 INTAKE AIR

TEMPERATURE

SENSOR SIGNAL

5089 BN 1.0

(3) 1.0

(3)

C8 EGR PINTLE

POSITION 1456 L-GN .7 .7 D8 BARO SENSOR

SIGNAL 432 L-GN 4-5 4-5

C9 RH OXYGEN

SENSOR SIGNAL 1666 GY 450

Mv (4) D9 NOT USED

C10 LEFT HAND

KNOCK SENSOR

SIGNAL

496 BU 1.3

A/C

1.9

A/C

D10 A/C PRESSURE

SENSOR SIGNAL 380 GN/BK 1-2 1-2

C11 RIGHT HAND

KNOCK SENSOR

SIGNAL

1876 L-BU 1.3

A/C

1.9

A/C

D11 ENGINE COOLANT

TEMPERATURE

SENSOR SIGNAL

410 YE 1.9

(3) 1.9

(3)

C12 BATTERY

VOLTAGE FEED 740 OG/BK 12 13 D12 BATTERY

VOLTAGE FEED 740 OG/BK 12 12

C13 UART PRIMARY

SERIAL DATA 800 RD/BK 3-5 3-5 D13 TRANS FLUID

TEMP (TFT)

SENSOR SIGNAL

1227 BK/YE 1.8

(3) 1.8

(3)

C14 INJECTOR

VOLTAGE

MONITOR LINE

639 RD 12 13 D14 NOT USED - - - -

C15 TP & A/C & BARO

PRESSURE

SENSOR

REFERENCE

VOLTAGE

416 GY 5 5 D15 NOT USED - - - -

C16 EGR, REFERENCE

VOLTAGE 5047 PU/WH 5 5 D16 IGNITION FEED 300 OG 12 13

(3) Varies with temperature.

(4) The voltage should vary between 100 mV - 1000 mV.

(5) 0.l25 - 1.25 volts measured between terminals "X2-C7" and "X2-B1" or about 4.0 volts at wide open throttle.

* Less than 0.50 volts

Normal

Volta

es Normal

Volta

This powertrain control module voltage Table is for use with a Digital Multimeter (DMM) to further aid in

diagnosis . Conn ect the B lack (-) probe to a goo d chass is ground, a nd back probe the powert rain c ontrol m odule

term inal with the Re d (+) probe. These v olt ages were der i ved f rom a k nown g ood ve hicle. T he vo lt ages you get

may vary due to low battery charge or other reasons, but they should be very close.

THE FOLLOWING CONDITIONS MUST BE MET BEFORE TESTING:

• Engine and Transmission at operating temperature

• Closed Loop

• Engine idling (for “Engine Run” column)

• TECH 2 not installed

• Accessories “OFF”

BACKPROBING VI EW OF TAN PCM CONNECTOR X3

Figure 6C1-2A-19 PCM Connector Terminal End View (3 of 3)

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

Pin Function

CKT

Wire

Colour

Ign

"ON"

Eng

Run

E1 NOT USED - - - - F1 FUEL INJECTOR

# 3 CONTROL 1746 PU 12 13

E2 FUEL INJECTOR

#2 CONTROL 1745 GN 12 13 F2 FUEL INJECTOR

#4 844 BN/YE 12 13

E3 NOT USED - - - - F3 PRNDL “A” 771 BLU/W * *

E4 FUEL INJECTOR

#1 CONTROL 1744 BU 12 13 F4 FUEL MODE

SWITCH (LPG ONLY) 5606 BU/OG * *

E5 FUEL INJECTOR

# 4 CONTROL 845 GY 12 13 F5 NOT USED - - - -

E6 FUEL INJECTOR

# 6 CONTROL 846 YE 12 13 F6 PRNDL “P” 776 WH * *

E7 SYSTEM GROUND 450 BK/RD * * F7 SYSTEM GROUND 450 BK/RD * *

E8 NOT USED - - - - F8 PRNDL “B” 772 YE 12 13

E9 PRESSURE

CONTROL

SOLENOID HIGH

1228 RD * 1.3 F9 PRNDL “C” 773 GY 12 13

E10 FUEL PUMP

RELAY CONTROL 465 GN/WH (1) 13 F10 NOT USED - - - -

E11 NOT USED - - - - F11 RANGE SIGNAL

"A" 1224 BN/YE 12 13

E12 EGR CONTROL

(PWM) 1676 PU 0.0 0.0 F12 RANGE SIGNAL

"B" 1225 YE 0 0

E13 PRESSURE

CONTROL

SOLENOID LOW

1229 GY/BU * 6.8 F13 RANGE SIGNAL

"C" 1226 GY 12 13

E14 NOT USED - - - - F14

POWER/ECONOMY

SWITCH INPUT 553 BU (6) (6)

E15 NOT USED - - - - F15 OIL PRESSURE

INPUT SI GN AL 31 BU/RD * 13

E16 LPG FCV

(LPG ONLY ) 5623 BK/BU (1) (1) F16

LPG

CONFIGURATION

(LPG ONLY )

300 OG 12 13

(1) Battery voltage first 2 seconds

(2) With air conditioning "ON" 0 volts, with air conditioning "OFF" 13 volts.

(6) W hen Power/Economy switch is depressed, voltage will momentarily change from 12 volts to 0 volts then back

to 12V.

(7) W ith engine cooling fan "ON" 0 volts, with engine cooling fan "OFF" 13 volts.

* Less than 0.50 volts.

Normal

Volta

Normal

Volta

es Normal

Volta

PCM CONNECTOR TERMINAL VOLTAGES WITH EXPLANATIONS

CONNECTOR X1

A1: 3-2 Downshift Control Solenoid Control

Automatic Transmission Only

The 3-2 control solenoid is a normally closed, ON – OFF solenoid used to control the 3-2 downshift. The solenoid is

constant l y fed 12 volts and PCM co ntro ls pat h to groun d.

A2: 2-3 Shift Solenoid “B” Control

Automatic Transmission Only

The PCM is used to either open or provide a path to ground for the 2-3 shift solenoid. W hen the PCM provides a

path to ground, the 2-3 shift solenoid is considered “ON” and the voltage should read 0 volts.

A3: LPG Enable (LPG Only)

When operating in the LPG Mode, the PCM supplies an LPG enable signal to the LPG smart unit from this

terminal.

A4: Not Used

A5: System Ground

This terminal is connected directly to the engine ground, the voltage on this terminal should be zero volts.

A6: Not Used

A7: Mass Air-Flow (MAF) Input Signal

The PCM supplies a 5-volt signal voltage to the mass air flow sensor on this circuit. The mass air flow sensor

pulses the 5-volt signal to ground. These ground pulses occur at a very fast rate, from less than 500 per second

(500 Hz) with no airflow through the sensor, to upwards of many thousands of pulses per second at high air flow

rates such as during acceleration. If measured, the voltage seen will be between 0.5 and 4.5 volts, depending on

air flow through the sensor.

A8: Start Relay Control

W hen the PCM receives th e proper T hef t Deterrent s ignal, the PCM will s upply a ground s igna l to Start Rel ay. This

will allo w t he ve hic le to start. If an impr oper Theft Deter r ent sig nal is sens e d by th e PC M, t he PCM wil l no t su pply a

ground signal to the Start Relay. This will prevent the starter motor from operating.

A9: Air Conditioning Relay Control

W hen the A/C is req uested , the BC M or OCC will com m unica te to the PCM via the s erial data line, r equesti ng A/C.

The PCM supplies the ground path on this terminal to energise the A/C control relay. The voltage will be less than 1

volt when the PCM energises the relay. When the PCM does energise the A/C control relay, the voltage will be

more than 0.1, but less than 1 volt.

A10: Canister Purge Solenoid Control

The PCM operates a normally closed solenoid valve, which controls vacuum to purge the evaporative emissions

storage canister of stored fuel vapours. The PCM turns “ON” the pulse width modulated control of the purge

solenoid, to control purging of the stored vapours. If the PCM is not energising the purge solenoid, the voltage

measured at this terminal should equal battery voltage. If the PCM is controlling the solenoid, the measured voltage

will be between battery voltage and 0.50 volts.

A11: Torque Converter Clutch, Pulse Width Modulated Apply Solenoid Control

Automatic Transmission Only

The PCM uses the pulse width modulated TCC apply solenoid to smoothly engage the torque converter clutch,

after the TCC “ON-OFF” solenoid is energised. By varying the duty cycle pulse width modulation, the PCM can

slowly engage the torque converter clutch, allowing very smooth TCC engagement.

A12: Torque Converter Clutch Enable Solenoid Control

Automatic Transmission Only

The PCM is used to either open or provide a path to ground for the torque converter solenoid. When the PCM

provides a path to ground, the T CC solen oid is co nsidered O N and volta ge shoul d be near 0 vol ts. The P CM uses

both the TCC enable solenoid and the TCC “PWM” solenoid to control the torque converter clutch.

B1: 1-2 Shift Solenoid “A” Control

Automatic Transmission Only

The PCM is used to either open or provide a path to ground for the 1-2 shift solenoid. W hen the PCM provides a

path to ground, the 1-2 shift solenoid is considered “ON” and the voltage should read 0 volts.

B2: Not Used

B3: Electronic Spark Timing (EST) Output

This terminal will have very low voltage with the ignition “ON” but engine not running. With the engine running at

idle, the voltage should be slightly more than 1 volt. As the engine RPM goes up, this voltage will increase.

B4: Ignition Module Bypass Control

Ignition System Mode Control

With ignition “ON” and engine not running this terminal will have very low voltage. As soon as the PCM sees engine

RPM of more than 450 RPM (Electronic Spark Timing “run” threshold) the PCM turns on 5 volts to the Ignition

Module Bypass Control circuit, causing the ignition module to allow the PCM to operate the ignition system.

B5: System Ground

This terminal is connected directly to the engine ground, the voltage on this terminal should be zero volts.

B6: Camshaft Position Input Signal

This signal is used by the PCM to “sequence” the energising of the fuel injectors, similar to the firing order of an

engine. This allows the PCM to operate the fuel injectors in a “sequential fuel injection” mode. The camshaft

position sensor is actually wired to the ignition module. The ignition module sends one pulse per every two

crankshaft revolutions to the PCM to determine actual camshaft position, and thus, engine cycle sequence.

B7: Crankshaft 18X Input Signal

The 18X cr ank s haf t ref erenc e input s i gna l is us ed to v ery accurate l y contr ol E ST s par k tim ing at lo w engine speeds

– below 1200 RP M. Below 1200 R PM, the PCM m onitors the 18X signal t o control spark timing. At eng ine speeds

above 1200 RPM, the PCM uses the 3X crankshaft reference input signal to control spark timing. (See 3X

crankshaft reference terminal X2-D12)

B8: Traction Control Torque Requested (MMR)

The ABS/TCS module will send a torque requested PWM signal to the PCM when torque reduction is requested

from the ABS/TCS module for traction control. This PW M signal should closel y match the Torque Achieved (MMI)

signal, when traction control is being requested.

B9: 3X Crankshaft Reference Input Signal High

This terminal could be called the “tacho” input. It provides the PCM with RPM and crankshaft position information.

With ignition “ON” but engine not running, t he voltage will be either hig h or low, depending on crank shaft position.

As the crank shaf t turns, the volta ge will be a n averag e of the two rea dings. T he PCM uses th e 3X signal to control

fuel injection, and spark timing with engine speeds above 1200 RPM.

B10: Cranks haft Reference Input Signal Low

This terminal should always be zero volts. It is connected through the ignition module to engine ground.

B11: Traction Control Torque Achieved (MMI)

The PCM sends a Torque Achieved PWM signal to the ABS/TCS module informing the ABS/TCS module of the

achieve d eng ine tor que. This PWM signal s hould match c losely the Requeste d Torque (MMR) s ignal, wh en trac tion

control is occur in g.

B12: Engine Cooling Fan High Speed Relay Control

This terminal will have battery voltage until the PCM energises the high speed cooling fan relay by supplying the

ground; then it will be close to zero. The inputs that cause the PCM to energise the high speed fan relay are the

engine coolant temperature and A/C pressure.

CONNECTOR X2

C1: Vehicle Speed Output To Speedometer

The PCM a lternatel y grounds this signa l, in puls es, when it r eceives a vehicle s peed signa l from the vehicle speed

sensor in the transmission. This pulsing action takes place about 6250 times per kilometre. The speedometer

calculates vehicle speed based on the time between pulses.

C2: Idle Air Control (IAC)

C3: Idle Air Control (IAC)

C4: Idle Air Control (IAC)

C5: Idle Air Control (IAC)

Thes e term inals connect th e Idle Air Control valve, located o n the throttle b ody, to the PCM. I t is diffic ult to predict

what the voltage will be, and the measurement is unusable for any service procedures.

C6: Engine Coolant Temperature and Throttle Position Sensor Ground

This terminal should be zero volts. It is connected through the PCM circuitry to engine ground.

C7: Throttle Position (TP) Sensor Signal

The TP sensor input voltage, which follows actual throttle changes, is variable from 0 to 5 volts. Typically the

voltage is less than 1 volt at idle, and 4 to 5 volts at wide-open throttle.

C8: Linear EGR Valve Pintle Position

This voltage is an indication to the PCM of the position of the EGR valve pintle. A low voltage indicates a fully

extended pintle (closed valve). A voltage near 5 volts indicates a retracted pintle (open valve).

C9: Right Hand Oxygen Sensor Input Signal

W ith ignit ion on a nd en gine not r un ni ng, the vol tag e s h oul d b e 350 – 450 mill ivolts (0.350 – 0 . 45 0 vo lts ). This is th e

PCM-sup plied c ircuit “bi as” vo ltage. W ith the e ngine runn ing an d after the ox ygen sens or is hot, t he vo lta ge shou ld

be rapidly changing, somewhere between 10 – 1000 millivolts.

C10: Left Hand Electronic Spark Control (ESC) Knock Input Signal

The Electronic Spark Control “knock” sensor detects when detonation is occurring in the combustion chambers.

W hen detected, the PCM will reduce t he amount of spark advance bein g deliver ed on the EST output circ uit to the

ignition module.

C11: Right Hand Electronic Spark Control (ESC) Knock Input Signal

The Electronic Spark Control “knock” sensor detects when detonation is occurring in the combustion chambers.

W hen detected, the PCM will reduce t he amount of spark advance bein g deliver ed on the EST output circ uit to the

ignition module.

C12: Battery Voltage Feed

Hot At All Times

This supplies the PCM with full-time +12 volts. It stays hot even when the ignition is turned off. It receives its

voltage through the “ENGINE” fuse. This PCM terminal could be called the power supply and “MEMORY” terminal.

C13: UART Primary Serial Data

The c ircuit conn ects the PCM to the B CM t he ABS, I nstrum ents , SRS, OC C an d Audio System are a lso c onnect ed

to this c irc uit v ia the BCM and th e s ec on dary and t er tia r y seria l d ata c irc uits. The Tech 2 c an “ ta lk ” to each of thes e

modules by sending a message to a controller and asking only it to respond. The communication rate is at 8192

baud. T he c ontro l modul es also “t a lk ” to each other vi a these s er ia l data c irc uits . T he voltag e o n this cir cuit wi th th e

ignition on will vary from zero to five volts, if read with a DVM will be approximatley 3-4 volts.

C14: Injector Circuit Voltage Monitor Input Signal

The inj ect or volt age monito r line is us ed s o th at the P C M wil l know the exac t vo lta ge the f uel i nj ec tors ar e op erating

at. This voltage signal is used to modify the fuel injector pulse width calculation.

C15: Throttle Position (TP) Sensor Reference voltage and A/C Refrigerant Pressure Sensor

This voltage should always be 5 volts anytime the ignition is “ON.” It is a regulated voltage output from the PCM,

and supplies 5 volts to the TP sensor and A/C Refrigerant Pressure Sensor.

C16: EGR Sensor Reference Voltage

This voltage should always be 5 volts anytime the ignition is “ON.” It is a regulated voltage output from the PCM,

and supplies 5 volts to the EGR valve.

D1: Vehicle Speed Sensor Output Shaft Speed Input Signal Low

The transmission has an output shaft speed sensor used by the PCM to calculate vehicle speed, and to help

determ ine vario us aut om atic transm is sion shif ting f unctions . It is a m agnetic induc tive s ensor th at gener ates an A C

voltage signal sent to the PCM. If measured with the digital AC voltmeter, no voltage will appear until the output

shaft begins turning.

D2: Vehicle Speed Sensor Output S haft Speed Input Signal High

The transmission has an output shaft speed sensor used by the PCM to calculate vehicle speed, and to help

determ ine vario us aut om atic transm is sion shif ting f unctions . It is a m agnetic induc tive s ensor th at gener ates an A C

voltage signal sent to the PCM. If measured with the digital AC voltmeter, no voltage will appear until the output

shaft begins turning.

D3: Left Hand Oxygen Sensor Ground

This terminal shoul d have zero volts. It is connected dir ectly to the engine gro und. This ter minal grou nds the PCM

circuitry for the oxygen sensor voltage monitor inside the PCM.

D4: Left Hand Oxygen Sensor Input Signal

W ith ignit ion on a nd en gine not r un ni ng, the vol tag e s h oul d b e 350 – 450 mill ivolts (0.350 – 0 . 45 0 vo lts ). This is th e

PCM supp lie d c irc u it “b ias ” vo lta ge. With the engine running a nd af ter the oxygen s ensor is hot , th e v olt ag e should

be rapidly changing, somewhere between 10 – 1000 millivolts.

D5: Right Hand Oxygen Sensor Ground

This terminal shoul d have zero volts. It is connected dir ectly to the engine gro und. This ter minal grou nds the PCM

circuitry for the oxygen sensor voltage monitor inside the PCM.

D6: Intake Air Temperature / Transmission Fluid Temperature / EGR Valve / A/C Pressure Sensor Ground

Circuit

This terminal should be zero volts. It is connected through the PCM circuitry to engine ground.

D7: Intake Air Temperature (IAT) Input Signal

The PCM sends a 5 volt signal voltage to the IAT sensor, which is a temperature variable resistor called a

thermistor. The sensor is also connected to ground, and will alter the signal voltage according to incoming air

temper atur e. As the air t em per ature i nc r eases , th e v olt age s e en on t his t er minal d ecr eas es. At zer o °C, the voltage

will be above 4 volts. At normal operating temperature (10 °C to 80 °C) the voltage will be less than 4 volts.

D8: Not Used

D9: Not Used

D10: A/C Refrigerant Pressure Sensor Input Signal

The signal that is sent from the pressure Sensor to the PCM indicates to the PCM what the A/C pressure is at.

Depending on the A/C pressure, this signal will indicate to the PCM if A/C pressure is too low or too high.

D11: Engine Coolant Temperature (ECT) Input Signal

The PCM sends a 5 volt signal voltage out to the engine coolant temperature sensor, which is a temperature

variable resistor called thermistor. The sensor, being also connected to ground, will alter the voltage according to

engine coolant temperature. As the engine coolant temperature increases, the voltage seen on terminal X2-D11

decreases. At zero °C engine coolant temperature the voltage will be above 4 volts. At normal operating

temperature (85 °C to 100 °C) the voltage will be less than 2 volts.

D12: Battery Voltage Feed

“HOT” At All Times

This supplies the PCM with full-time +12 volts. It stays “hot” even when the ignition is turned off. It receives its

voltage through the ENGINE fuse. This PCM terminal could be called the power supply and “MEMORY” terminal.

D13: Transmission Fluid Temperature (TFT) Input Signal

Automatic Transmission Only

The PCM sends a 5 volt signal voltage out to the transmission fluid temperature sensor, which is a temperature-

variab le-resis tor cal led a th erm istor . The sensor , being also c onnected t o gro und, wil l alter th e volt age acc ording t o

transmission fluid temperature. As the fluid temperature increases, the voltage seen on the PCM terminal will

decrease.

D14: Not Used

D15: Not Used

D16: Ignition Switch Input Signal

This is the “ tur n on” s igna l t o the P CM f r om the ign ition s witch c irc u it. It is no t the “po wer supp ly” to the PCM, it on l y

tells the PC M t hat the igniti on switch is “ ON.” The vo lt age s h ou ld equal the batter y vol tag e when the k e y is i n e ither

the “run“ or “crank“ position.

CONNECTOR X3

E1: Not Used

E2: Fuel Injector #2 Control

The voltage seen a t these terminals actually com es through the injectors, which are connect ed to +12 volts. With

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

E3: Not Used

E4: Fuel Injector #1 Control

The voltage seen at these terminals actually comes through the injectors, which are connected to +12 volts. W ith

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

E5: Fuel Injector #4 Control

The voltage seen at these terminals actually comes through the injectors, which are connected to +12 volts. W ith

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

E6: Fuel Injector #6 Control

The voltage seen at these terminals actually comes through the injectors, which are connected to +12 volts. W ith

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

E7: System Ground

This terminal is connected directly to the engine ground, the voltage on this terminal should be zero volts.

E8: Not Used

E9: Transmission Pressure Control Solenoid (PCS) High

Automatic Transmission Only

The dut y cycle, an d am ount of c urrent f low to the PCS , are contr olle d by the PC M. T his c ircuit is the B+ su pply lin e

from the PCM to th e PCS. The duty c ycle and amperage ar e c ontro lle d b y the PCM. A high c urr ent ou tput in dic ates

low transmission fluid pressure, while a low current output would indicate high fluid pressure.

E10: Fuel Pump Relay Control

Turning the ignition “O N” causes the PCM t o energise (+12V) the fuel pump relay. If no cranks haft reference inp ut

pulses are received, the PCM turns off the relay. As soon as the PCM receives crankshaf t reference input pulses,

the PCM will turn the fuel pump relay on again.

E11: Not Used

E12: EGR Control

The PCM monitors EGR actual position and adjust a pintle position accordingly. The PCM uses information from

several sensors to control the pintle position. The PCM provides a PWM 12 volt control signal (% Duty) for EGR

operation.

E13: Transmission Pressure Control (PCS) Solenoid Low

Automatic Transmission Only

The 4L60-E automatic transmission uses an electrical solenoid to control hydraulic pressure inside the

transmission. This electrical solenoid allows the PCM to control “line pressure”, similar to other automatic

transm issions that use a “thr ottle valve” cabl e or vacuum modulator. The dut y cycle, and am ount of current f low to

the PCS, are both controlled by the PCM. By monitoring this line, the PCM can determine if the commanded

amperage has gone to the PCS and returned to the PCM.

E14: Not Used

E15: Not Used

E16: LPG Fuel Control Valve (LPG Only)

This is the PCM output PWM signal to the Fuel Control Valve for LPG air/fuel ratio adjustment.

F1: Fuel Injector #3 Control

The voltage seen at these terminals actually comes through the injectors, which are connected to +12 volts. W ith

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

F2: Fuel Injector #4 Control

The voltage seen at these terminals actually comes through the injectors, which are connected to +12 volts. W ith

the engine not running, the voltage seen would be battery voltage. With the engine running at idle, the charging

system increases the voltage slightly, so this voltage will increase. With higher engine RPM or more engine load,

the resulting increase in injector pulse frequency or injector pulse width will cause this voltage to appear slightly

less.

F3: PRNDL “A”

Automatic Transmission Only

These circuits alo ng with PCM circuit F6 indicate to the PCM what transm ission gear the driver has selected. The

PCM will then send a com mand via the seria l data li ne to the instrum ent panel c luster ( smart c luster) to ind icate to

the driver what gear has been selected.

F4: Fuel Mode Switch (LPG Only)

This is the input s ignal from the f uel mode switch indicating to the PCM that the driver has requested a ch ange in

the fuelling mode, either LPG or Petrol.

F5: Not Used

F6: PRNDL “P”

Automatic Transmission Only

This circuit a long with P CM c ircuits F3, F 8, F9 indic ate to the PC M what transm is sion gear the driver has s elec ted.

The PCM will then send a command via the serial data line to the instrument panel cluster (smart cluster) to

indicate to the driver what gear has been selected.

F7: System Ground

This terminal is connected directly to the engine ground, the voltage on this terminal should be zero volts.

F8: PRNDL “B”

Automatic Transmission Only

These circuits alo ng with PCM circuit F6 indicate to the PCM what transm ission gear the driver has selected. The

PCM will then send a com mand via the seria l data li ne to the instrum ent panel c luster ( smart c luster) to ind icate to

the driver what gear has been selected.

F9: PRNDL “C”

Automatic Transmission Only

These circuits alo ng with PCM circuit F6 indicate to the PCM what transm ission gear the driver has selected. The

PCM will then send a com mand via the seria l data li ne to the instrum ent panel c luster ( smart c luster) to ind icate to

the driver what gear has been selected.

F10: Not Used

F11: TFP Manual Valve Position Switch Range Signal “A” Input Signal

Automatic Transmission Only

Range signal “A”, “B” and “C”. The PCM sends out a buffered 12 volt signal to the pressure switch assembly,

located in the automatic transmission valve body. The 12 volt signal must pass through either a normally open or

norm all y clos ed s w itch to r eac h gro und . When the switches are c l os ed, t he s igna l s houl d b e ne ar 0 volts . The PCM

monitors the status of these signals to determine which gear servo is actually receiving hydraulic apply pressure.

F12: TFP Manual Valve Position Switch Range Signal “B” Input Signal

Automatic Transmission Only

Range signal “A”, “B” and “C”. The PCM sends out a buffered 12 volt signal to the pressure switch assembly,

located in the automatic transmission valve body. The 12 volt signal must pass through either a normally open or

norm all y clos ed s w itch to r eac h gro und . When the switches are c l os ed, t he s igna l s houl d b e ne ar 0 volts . The PCM

monitors the status of these signals to determine which gear servo is actually receiving hydraulic apply pressure.

F13: TFP Manual Valve Position Switch Range Signal “C” Input Signal

Automatic Transmission Only

Range signal “A”, “B” and “C”. The PCM sends out a buffered 12 volt signal to the pressure switch assembly,

located in the automatic transmission valve body. The 12 volt signal must pass through either a normally open or

norm all y clos ed s w itch to r eac h gro und . When the switches are c l os ed, t he s igna l s houl d b e ne ar 0 volts . The PCM

monitors the status of these signals to determine which gear servo is actually receiving hydraulic apply pressure.

F14: Power/Economy Switch Input Signal

Automatic Transmission Only

The PCM sends a signal of about 12 volts, and monitors the status of this circuit. In the economy position the

switch is open, the PCM vo ltage status s ignal rem ains high, abo ut 12 volts, an d the PCM does not all ow shift point

changes. W hen the transmission switch is pressed to the power position the switch is momentarily closed and the

PCM voltage status signal is momentarily pulled low. The PCM senses the momentary voltage signal drop and

enables power mode shifting only if other criteria are met. These criteria include throttle position and engine speed.

F15: Oil Pressure Switch

This input to the PCM from the Oil Pressure Switch indicates oil pressure when the engine is running. If oil pressure

is lost while the engine is running, the oil switch will close its contacts and the 12 volt signal to the PCM will be

removed. When the PCM sees this loss of signal, the PCM will command the instruments to activate the oil

pressure lamp, via the normal mode message.

F16: LPG Wiring Configuration (LPG Only)

This is the LPG configuration signal to the PCM from the ignition switch circuit. It is not the “power supply” to the

PCM, it only tells the PCM that the vehicle is equipped with LPG and enables the PCM to operate in either the

petrol and LPG modes.

V6 PCM ENGINE AND TRANSMISSION DIAGNOSTIC TROUBLE CODES (DTC)

DTC

DESCRIPTION CHECK

POWERTRAIN

MIL ACTIVATED

P0012 No revolutions per minute signal – normal when engine is not running No

P0101 Mass Air Flow (MAF) Sensor Out of Range Yes

P0107 Barometric (Baro) Pressure Sensor Signal Voltage Low No

P0108 Barometric (Baro) Pressure Sensor Signal Voltage High No

P0111 Intake Air Temperature Signal Voltage Unstable No

P0112 Intake Air Temperature Signal Voltage Low No

P0113 Intake Air Temperature Signal Voltage High No

P0117 Engine Coolant Temperature Signal Voltage Low Yes

P0118 Engine Coolant Temperature Signal Voltage High Yes

P0121 Throttle Position Sensor Stuck Yes

P0122 Throttle Position Sensor Voltage Low Yes

P0123 Throttle Position Sensor Voltage High Yes

P0131 Right Hand Oxygen Sensor Signal Voltage Low Yes

P0132 Right Hand Oxygen Sensor Signal Voltage High Yes

P0134 No Right Hand Oxygen Sensor Signal Yes

P0151 Left Hand Oxygen Sensor Signal Voltage Low Yes

P0152 Left Hand Oxygen Sensor Signal Voltage High Yes

P0154 No Left Hand Oxygen Sensor Signal Yes

P0170 Long Term Fuel Trim (LTFT) Delta High No

P0173 Short Term Fuel Trim (STFT) Delta High No

P0200 Injector Voltage Monitor Fault No

P0218 Transmission Fluid Overtemperature Yes

P0325 DSNEF System Fault Yes

P0327 Left Hand Knock Sensor Circuit Fault Yes

P0332 Right Hand Knock Sensor Circuit Fault Yes

P0341 Cam/Crank Sensor Signal Intermittent No

P0342 Camshaft Posit ion Sens or Sig na l Miss ing No

P0374 18X Reference Signal Missing No

P0 400 EGR Flow Fault Indicated No

P0405 EGR Position Fault No

P0446 Canister Purge Circuit Fault No

P0502 No Vehic le Spe ed Si gna l Yes

P0503 Vehicle Speed Sensor Intermittent Signal No

P0506 Idle Speed Error No

P0507 Vacuum Leak No

P0530 A/C Refrigerant Pressure Sensor Circuit Fault No

P0560 System Voltage Too High (Long Time) Yes

P0561 System Voltage Unstable Yes

P0562 System Voltage Low Yes

P0563 System Voltage Too High Yes

P0601 Powertrain Control Module Memory Yes

P0712 Transmission Fluid Temperature Signal Voltage Low No

P0713 Transmission Fluid Temperature Signal Voltage High No

DTC

DESCRIPTION CHECK

POWERTRAIN

MIL ACTIVATED

P0730 2-3 Shift Solenoid B Circuit Voltage High Yes

P0740 Torque Converter Clutch Enable Solenoid Circuit Fault Yes

P0741 Torque Converter Clutch System Stuck On No

P0748 Pres sur e Contr ol So le noi d Curr ent Er ror No

P0753 1-2 Shift Solenoid A Circuit Voltage High Yes

P0756 1-2 Shift Solenoid A Circuit Voltage Low Yes

P0757 2-3 Shift Solenoid B Circuit Voltage Low Yes

P0785 3-2 Down-Shift Control Solenoid Circuit Fault Yes

P1064 Low Spe ed Fan – No BCM Response No

P1116 Engine Coolant Temperature Signal Voltage Unstable No

P1255 Theft Deterrent Signal Missing Yes

P1351 Ignition Electronic Spark Timing (EST) Circuit Fault Yes

P1361 Ignition Bypass Circuit Fault Yes

P1372 No Reference Pulses While Cranking Yes

P1571 Requested Torque Out Of Range Yes

P1627 PCM - Analog to Digital (A/D) Conversion Error Yes

P1628 PCM Error – Engine Coolant Temperature Circuit No

P1642 LPG Enable Signal Out Of Range No

P1643 LPG FCV PWM Signal Out Of Range No

P1810 Transmission Fluid Pressure Manual Valve Position Switch Assembly

Circuit Ma lf unc tion Yes

P1860 Torque Converter Clutch Pulse Width Modulation Solenoid Fault No

P1870 Transmission Slipping No

4L60-E TR ANSMISSION FLUID CHECKING PROCEDURE

GENERAL INFORMATION

W hen adding or chan ging t he transm is sion fluid, use onl y Dexron® III. Ref er to th e MY200 3 Owner's Han dbook for

the recommended servicing intervals.

Because this transmission fluid changes colour and smell very easily in its life, these indicators should not

necessarily be relied upon to diagnose either transmission internal condition or fluid deterioration.

The Fluid Chec king Proc edure shows th at a dark br own fluid colour, cou pled with a dela yed shift patter n, may onl y

indicate that the fluid requires replacement and alone, is not a definite indication of a potential transmission failure.

NOTE: Do not o verfill th e trans miss ion. Overfillin g will cause f oaming of the fluid, loss of fluid, s hift com plaints and

possible damage to the transmission.

TRANSMISSION FLUID COLOUR

Transmission fluid colour when new and unused, is red. A red dye is added so that it can be distinguished from

other oils and lubricants. The red dye is not an indicator of fluid quality and is not permanent. As the vehicle is

driven, the transmission fluid will quickly begin to look darker in colour. The colour will then appear light brown. A

DARK brown colour with a distinctively burnt odour MAY indicate fluid deterioration and a need for the fluid to be

changed.

TRANSMISSION FLUID CHECKING PROCEDURE

1. Start the engine and drive vehicle for a maximum of 24 km, or until the transmission normal operating

temperature is reached.

NOTE: As temperature greatly affects transmission fluid levels, this operation must only be carried out when the

transm ission is at norm al operating tem perature (82 – 94° C). If the vehicle is not at normal oper ating tem perature,

and the proper checking procedures are not followed, the result could be a false reading of the fluid level on the

dipstick.

2. Park vehicle on level ground.

3. Move gear selector to 'PARK' position.

4.. Apply park brake.

5. Let engine idle for 3 minutes with accessories turned off.

6. Locate red coloured dipstick in the engine compartment, lift the locking lever, remove the dipstick and check

fluid colour, condition and level.

7. If the fluid level is low, add only enough DEXRONâ III to bring the level into the "HOT" area.

NOTE: Inaccurate fluid level readings will result if checked immediatel y after the vehicle has been op erated under

any or all of the following conditions:

a. In high ambient temperatures above 32° C.

b. At sustained high speeds.

c. In heavy city traffic during hot weather.

d. Towing

e. In commercial use (e.g. taxi).

If the vehicle has been operated under these conditions, switch the engine off and allow the vehicle to 'cool' for

approximately thirty minutes. After cool-down period, re-start the vehicle and continue from step 2.

4L60-E AUTOMATIC TRANSMISSION FLUID CHECKING PROCEDURE

STEP ACTION VALUE YES NO

1. Check the fluid colour.

Is the fluid colour red? Go to Step 2 Go to Step 11

2. Is the fluid level satisfactory? Go to Step 20 Go to Step 3

3. Check the fluid.

Is the fluid foamy? Go to Step 8 Go to Step 4

4. Check the fluid level. The proper fluid level should be in

the middle of the X-hatch.

Is the level high?

Go to Step 9 Go to Step 5

5. Fluid will be low.

Add fluid to the proper fluid level.

Is the fluid level satisfactory?

Go to Step 6 Go to Step 1

6. Check for external leaks.

Were any leaks present? Go to Step 7 Go to Step 20

STEP ACTION VALUE YES NO

7. Correct the fluid leak condition.

Is action complete? Go to Step 20

8. Is the fluid level too high? Go to Step 9 Go to Step 10

9. Remove excess fluid to adjust to the proper fluid level.

Is action complete? Go to Step 20

10. 1. Check for contaminants in the fluid.

2. Drain the fluid to determine the source of the

contamination.

Is action complete?

Go to Step 15

11. Is the fluid colour non-transparent pi nk? Go to Step 12 Go to Step 13

12. Replace the cooler.

Is action complete? Go to Step 15

13. The fluid colour should be light brown. Transmission fluid

may turn dark with normal use. This does not always

indicate oxidation or contamination.

Is the fluid colour light brown?

Go to Step 14 Go to Step 1

14. Drain the fluid to determine if the fluid is contaminated.

A very small amount of material in the bottom of the pan

is a normal condition, but large pieces of metal or other

material in the bottom of the pan requires a transmission

overhaul.

Was the fluid contaminated?

Go to Step 15 Go to Step 18

15. Overhaul the transmission. Refer 7C5, UNIT REPAIR.

Is action complete? Go to Step 16

16. Flush the cooler.

Is action complete? Go to Step 17

17. Add new fluid.

Is action complete? Go to Step 19

18. Change the fluid and filter.

Is action complete? Go to Step 19

19. Is the fluid level satisfactory, If not, correct as necessary.

Is action complete? Go to Step 20

20. Refer 4L60-E Transmission Functional Test Procedure, in

7C3, DIAGNOSIS.

Is action complete?

Fluid Checking

Procedure

Completed

TABLE A V6 PCM - ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK

Figure 6C1-2A-20 – Check Powertrain MIL and UART Serial Data Circuit

CIRCUIT DESCRIPTION

The On-Board Diagnostic System Check is an organised approach in identifying a problem created by a powertrain

control system malfunction. It must be the starting point for any driveability complaint diagnosis, because it directs

the service technician to the next logical step in diagnosing the complaint. Understanding the Table and using it

correctly will reduce diagnostic time and prevent the unnecessary replacement of good parts.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

1. Confirms TECH 2 operation and that TECH 2 is being powered up.

2. This check is used to establish if the PCM can supply serial data for TECH 2 use. If the PCM is capable of

communicating serial data to TECH 2, the PCM power supply, ground and the serial data line are OK. If TECH

2 displays “Incorrect Selection or Unknown Software” check that you have selected the correct Model Year,

Vehicle Type and Engine, if these selections were correct, check the PCM has the correct software loaded from

TIS 2000 Service Programming System.

3. This check is to see if there is a Theft Deterrent DTC stored. If the PCM has not received a valid theft deterrent

signal from the BCM a DTC P1225 should set, this may be the cause of a ‘no crank’ condition.

4. This test determines if the vehicle is able to crank. If the vehicle will not crank, refer to Table A-4.0 to diagnose

the starter cranking circuit.

5. This test determines if any DTCs are stored in the PCM memory. To determine if a DTC is current, select DTC

History and refer to “Ignition Cycles Since”.

6. This test is used to determine the cause of a "Cranks But Will Not Run," although the PCM is powered up, a

"Cranks But Will Not Run" symptom could exist because of a PCM problem or the vehicle electrical system.

7. Look at all the parameters to determine if one is not in a normal state with just the ignition "ON" and engine

stopped. For example, look at the ECT value to see if the value is shifted above or below where it should be. If

so, refer "Diagnostic Aid Table" on DTC P0117.

8. Look at all the parameters to determine that all values are within typical ranges for normal operating

temperatures at idle. Keep in mind that a basic engine problem may alter sensor values.

DIAGNOSTIC AIDS

If the Serial Data circuit is shorted to voltage or ground or open, the vehicle will not crank. Check Serial Data circuit

from PCM to BCM, and from BCM to all other controllers.

TABLE A V6 PCM – ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK

STEP ACTION VALUE YES NO

1. 1. Turn ignition off, install TECH 2 to DLC, turn ignition

on and turn on TECH 2.

Does TECH 2 power up and display the title display

screen?

Go to Step 2 Refer TECH 2

Diagnosis,

Section 0C

TECH 2 in this

Service

Information.

2. 1. From the TECH 2 engine application menu select

V6 Engine.

Does TECH 2 display Identification Data?

Go to Step 3 Go to Table A-2

in this Section

3. 1. Ignition "ON".

2. Using TECH 2, check for DTC P1255.

3. Is DTC P1225 set?

Go to DTC

P1225 Table

Go to Step 4

4. Does engine crank?

Go to Step 5 Go to

Table A-4.0

5. 1. Using TECH 2, select Current DTC(s).

Are any Diagnostic Trouble Codes displayed?

Refer to

Applicable DTC

Table.

Start with lowest

DTC

Go to Step 6

6. Does engine start and continue to run?

Go to Step 7 Go to

Table A-3.1

7. 1. Ignition "ON", engine "STOPPED".

2. Compare TECH 2 data with “Typical Data Values”.

Are values normal or within typical ranges?

Go to Step 8 Refer to

indicated

"Component(s) –

System" checks

in this Section.

8. 1. Run engine until normal operating temperature is

reached.

2. Run engine at 1500 revolutions per minute for 2

minutes, then idle engine.

3. Compare TECH 2 scan data with “Typical Data

Values”.

Are values normal or within typical ranges?

Refer to

"Symptom"

Diagnosis

Tables" in

Section 6C1-2B

in this Section.

Refer to

indicated

"Component(s) –

System "checks

in this Section.

TABLE A-1 V6 PCM -

NO CHECK POWE RTRAIN MALFUNCTION INDICATOR LAMP (MIL)

Figure 6C1-2A-21 – Check Powertrain Malfunction Indicator Lamp (MIL) Circuit

CIRCUIT DESCRIPTION

The Powertrain Control Module (PCM) controls the lamp via serial data communication to the Instrument on the

serial dat a circu it. W hen the PCM determ ines that the Check Po wertrain MIL sh ould be "ON", the PCM will s end a

mess age to the instrum ent s via the s erial d ata circ uit nor m al mode m essage, r equestin g the Check Powertr ain MI L

"ON”. The Instrument will then activate the Check Powertrain MIL.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. This test confirms that the Instrument MFD has passed its system check.

3. Disc onnect ing the Mas s Air Flo w Se nsor s hou ld caus e DTC P0101 to s e t an d th e PCM to c om mand the C he ck

Powertrain Lamp “ON” via the serial data normal mode message. If the DTC does not set then the internal

diagnostics of the PCM are not functioning correctly.

4. This test checks that the serial data normal mode message displays "ON" when the DTC sets.

A84 V6 – X1 A84 V6 – X2 A84 V6 – X3

X40 P3

Figure 6C1-2A-22

TABLE A-1 V6 PCM – NO "CHECK POWERTRAIN" MALFUNCTION INDICATOR LAMP (MIL)

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. 1. Turn the ignition "ON".

2. Observe the Instrument Multi Function Display

(MFD).

Does the MFD display "OK!" once the “System Check” is

completed?

Go to Step 3 Refer 12C in this

Service

Information

3. 1. Disconnect the Mass Air Flow Sensor connector

B68.

2. Start the engine and allow to idle for 20 seconds.

Does the MFD display the "Check Powertrain MIL"?

Check

Powertrain MIL

is operating

correctly

Go to Step 4

4. 1. Connect TECH 2 to DLC.

2. With TECH 2 connected, select F0: Norm al Mode.

3. With the Mass Air Flow Sensor connector B68 still

disconnected.

4. Start the engine and monitor the "Normal Mode"

data display.

Does the "Normal Mode" display "Check Powertrain

Lamp" display "ON"?

Refer 12C in this

Service

Information

Go to Step 5

5. 1. Replace PCM. Refer to 6C1-3 Service Operations,

for PCM Security Link procedure

Is action complete?

Verify Repair

TABLE A-2 V6 PCM – NO SERIAL DATA

Figure 6C1-2A-23 – Serial Data Circuit

CIRCUIT DESCRIPTION

The VY and V2 series of vehicles use a “Bus Master” communication system, where the BCM is the bus master.

The BCM periodically polls (surveys) each control module on the bus (serial data circuit) and requests status data.

The control modules connected via the serial data circuit are the (PCM, BCM, ABS/TCS module, OCC module,

SDM, Instrument, Audio System and Telematics Module, TECH 2 communicates with these modules via the serial

data circuit and DLC terminal 9. Any one of these modules could cause a fault on the serial data line. This fault

could result in TECH 2 not being able to display serial data.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. This step checks to see if TECH 2 will communicate with the PCM.

3. This step checks to see if TECH 2 will communicate with the BCM.

4. Using a Digital Multi Meter (DMM), there should be 3 to 4.5 volts at the DLC terminal 9. If the voltage is higher

or lower, serial communication will be affected. This serial data circuit is also connected to several other

modules. A problem with any one of these other modules, may cause a serial data communication malfunction.

5. If the voltage at DLC terminal 9 is at or above 5 volts the serial data circuit is shorted to voltage. If the voltage is

0 volts the serial data circuit may be open or shorted to ground.

6. This step checks the PCM power supply circuit 740. There should be battery voltage at these terminal at all

times.

7. This step checks the PCM ignition circuit 300. There should be battery voltage at this terminal when the ignition

is on.

8. This step checks the continuity of the four PCM ground circuits. All four ground circuits should be checked for

continuity.

9. If the voltage at DLC terminal 9 is at or above 5 volts the serial data circuit is shorted to voltage. If the voltage is

0 volts the serial data circuit may be open or shorted to ground.

DIAGNOSTIC AIDS

If there is a fault with the serial data circuit, it could be caused by one or more of the several modules connected to

this serial data circuit. Isolate the fault by disconnecting each controller (one at a time), until the serial data

communication is restored.

A84 V6 – X1 A84 V6 – X2 A84 V6 – X3

X40

Figure 6C1-2A-24

TABLE A-2 V6 PCM – NO SERIAL DATA

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed?

Go to Step 2 Go to

OBD System

Check

2. 1. Connect Tech 2 to DLC.

2. Ignition "ON", engine stopped.

Does Tech 2 display PCM serial data?

No trouble found Go to Step 3

3. 1. Connect Tech 2 to DLC.

2. Ignition "ON", engine stopped.

Does Tech 2 display BCM serial data?

Go to step 6 Go to Step 4

4. 1. Ignition "ON", engine stopped.

2. Using DMM, probe DLC terminal 9 with DMM

connected to ground.

Does DMM display voltage varying between the

specified value?

3 – 4.5 volts Go to Step 15 Go to Step 5

5. Is voltage steady at or above the specified value? 5 volts Go to Step 10 Go to Step 11

6. 1. Ignition "ON", engine stopped.

2. Using DMM, check for voltage at PCM power

supply circuit 740 terminals X2-C12 and X2-D12.

Does DMM display the specified value at both

terminals?

B+ Go to Step 7 Go to Step 12

7. 1. Ignition "ON", engine stopped.

2. Using DMM, check for voltage at PCM ignition

supply circuit 300 terminal X2-D16.

Does DMM display the specified value?

B+ Go to Step 8 Go to Step 13

8. 1. Using DMM, check continuity of the four PCM

ground circuits 450, between PCM terminals

X1-A5, X2-D6, X3-E7 & X3-F7 and a known good

ground.

Do all four ground circuits have continuity?

Go to Step 9 Go to Step 14

9. Check for open in the serial data circuit 800 between the

PCM and the DLC.

Is the circuit open?

Verify Repair Go to step 16

10. Repair short to voltage on the serial data circuit.

NOTE: Ensure that none of the other modules on the

serial data circuit are causing this voltage problem.

Unplug each module one at a time to isolate short to

voltage.

Is action complete?

Verify Repair

11. Repair short to ground or open in the serial data line.

NOTE: Ensure that none of the other modules on the

serial data circuit are causing this voltage problem.

Unplug each module one at a time to isolate short to

ground.

Was a problem found?

Verify Repair Go to Step 16

12. Repair open in PCM power suppy circuit 740.

Was a problem found?

Verify Repair

13. Repair open in PCM ignition circuit 300.

Was a problem found?

Verify Repair

14. Repair open in PCM ground circuit 450.

Was a problem found?

Verify Repair

15. 1. Refer to BCM No Serial Data diagnostics in Section

12J BCM in this Service Information.

Is action complete?

Verify Repair

16. 1. Replace PCM. Refer to 6C1-3 Service Operations,

for PCM Security Link procedure

Is action complete?

Verify Repair

TABLE A-3.1 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

Figure 6C1-2A-25 – Injector Circuit

CIRCUIT DESCRIPTION

This is the f irst of sever al diagnos tic Tables that m us t be fol lowed in an orderl y, p rogres sive f ashion in or der to find

the cause of a no-start. These Tables assume an a dequate suppl y of goo d quality fue l is in the fuel tank, that the

cranking motor circuit is in good working order, and that the engine will crank with adequate RPM. These Tables

also assu m e that no Diagn ostic T rouble Cod e (DT C) P1255 or P1372 is s et in the PCM m em or y, as det erm ined by

the On-Boar d Diagn ostic S ystem Check . The On- Board Diagnos tic S ystem Check is always the be ginni ng point f or

all diagnostic procedures.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

1. The PCM must be operable. The On-Board Diagnostic System Check will prove that. There are few chances

that the PCM itself would cause a no-start, but the On-Board Diagnostic System Check will uncover any

problems in the PCM power and ground circuitry.

4. NOTE: If the vehicle is fitted with LPG, and if the vehicle will not start in the LPG mode only, and no DTC

P1642 is s et, PC M ter minal X 1- A3 cir cuit 253 1 ma y be shorted to v olt age. R efer Sect ion 8A2 LPG SYSTEM in

this Service Information for further diagnosis of the LPG system.

This checks for a short to ground on the injector control circuit. If this were to occur, the engine would be

extrem ely flooded, since the injectors would be "ON " contin uously, and would inj ect fuel an y time there is fuel

pressure.

5. Any time the PCM has been "OFF" for at least 10 seconds, it should energise the Fuel Pump Relay for 2

seconds after the ignition is turned "ON." If the engine is not cranked, the PCM should turn the relay "OFF"

after 2 s econds. Pr oper oper ation of the Fuel Pum p elec trical c ircuit would be not ed here b y the test lig ht being

"ON" f or 2 sec onds after the i gnitio n sw itch is turn ed to th e "O N" pos itio n. Af ter 2 seconds , the test light s ho uld

go "OFF."

6. Note that this check is for sufficient voltage at the spark plug wire. If, for some reason, the spark plug

electrodes were wet with fuel (engine flooded), this could cause a no-start. However, a "flooded" engine is a

symptom of some other problem. There is no normal condition that should ever be able to "flood" the engine.

7. T his is a quick check of the f uel s ystem. T he easiest plac e to ins tall th e press ure gaug e is where th e fuel p ipes

come up into the engine compartment. There are 2 hoses, and the gauge must be connected to the hose or

pipe lea ding direc tly to the f uel rail. This connection is on the lef t (passenger ) side of the fuel rail (r efer Servic e

Operation 3.4 FUEL CONTROL SYSTEM; Fuel System Pressure Test in this Service Information). The

other hos e or pipe lea ds to the pres sure reg ulator, an d no pressur e testin g is done ther e. If the press ure is not

as specif ied, or continues to drop after the pum p stops running, the Fuel System Diagnostic Table A-4.3 m ust

be used.

NOTE: Us e ST 125 spark check er or equival ent. An ST 125 requires a bout 25, 000 volts (25 k ilovolts , or 25 k V) to

"spark". Do not use a spark plug in open air grounded to the engine as an indication of sufficient "spark". Only a

few kilovolts are required to jump the gap of a spark plu g outside of the engine, and that would be an inadequate

test of the ignition coil output ability.

X 16 (PART OF X100)

Figure 6C1-2A-26

TABLE A-3.1 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. Is DTC P1255 present? Go to DTC

P1255 Table Go to Step 3

3. Is DTC P1372 present? Go to DTC

P1372 Table Go to Step 4

4. NOTE: If this vehicle is fitted with LPG and the engine will

not start in the LPG mode only, and DTC P1642 is not

set, check the LPG Enable circuit 2531 at PCM terminal

X1-A3 for a short to voltage.

1. Check fuel tank quantity.

2. Disconnect ALL injector electrical connectors.

3. Connect test light between the terminals of each

injector harnes s conne ctor.

Be very careful to NOT short across the terminals, or to

engine ground.

4. Ignition "ON", note test light.

Is light "OFF" on all six injector connectors?

Go to Step 5 Go to Step 8

5. 1. Probe Fuel Pump Relay X16 5 circuit with a test light

connected to ground.

2. Ignition "ON".

3. Using TECH 2, Select Fuel Pump.

4. Activate Fuel Pump.

Is test light "ON"?

Go to Step 6 Go to

Table A-4.1

6. 1. Ignition "O FF".

2. Remove the spark plug leads from 2 spark plugs.

3. Connect ST 125 spark checker (refer Test

Description) to each individually, and check for spark

while cranking the engine.

4. Check both wires. A few sparks and then nothing is

consider ed no spar k.

Was there spark on both wires?

Go to Step 7 Go to

Table A-8.1

7. 1. Ignition "O FF".

2. Reconnect both spark plug leads to spark plugs.

3. Reconnect all injector electrical connectors.

4. Remove Fuel Pump Relay from engine compartment

"FUSE AND RELAY CENTRE," and crank engine for

15 seconds to relieve any residual fuel pressure.

5. Ignition "OFF," connect Fuel Pr ess ure Gauge

(Gauge to be installed in the pressure line, between

the fuel feed hose and the fuel inlet line to the fuel

rail, at left rear of fuel rail.)

6. Reinstall Fuel Pump Relay

7. Observe fuel pressure when ignition is turned "ON."

8. Pressure should be within the specified value, and

not continue to drop after pump stops running.

Is fuel pressure at or between the specified value?

270 to 350

kPa Go to

Table A-3.2 Go to

Table A-4.3

8. Check for short to ground on Injector Circuit.

Was Injector Circuit shorted to ground? Verify Repair Go to Step 9

9. Replace PCM.

Refer to 6C1-3 SERVICE OPERATIONS, for PCM

Programming and Security Link procedure.

Is action complete?

Verify Repair

TABLE A-3.2 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

Figure 6C1-2A-27 – Injector Circuit

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

3. "STEAD Y LIG HT" indic at es the PC M is c o nti nuo us l y supp l ying th e gr o und pat h on the i nj ec tor c irc uit. It is no t a

harness pr oblem at this point. T hat would have b een identif ied in T able A-3.1. T his ma y destr oy an injector , as

they are designed to be energised in short pulses and may not withstand 100% "ON" time. If any injector

checks less than 11.4 ohms, it could be the cause of the defective PCM. The PCM can be damaged when it

attempts to energise the injector circuit with a very-low-resistance load. Normal injector resistance is

approximately 12.2 ohms at 20°C per individual injector.

Figure 6C1-2A-28 – Injector Circuit

TABLE A-3.2 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. • From Table A-3.1.

1. Ignition "OFF".

2. With all injectors disconnected, connect test light

across both harness terminals of one injector

connector.

Be very careful to not short across the terminals, or

to engine ground.

3. Have a helper crank the engine while you closely

observe the test light.

4. Test light should blink while cranking, indicating

electrical injector pulses are present, do this test for

all injectors.

Did test light blink on all injector circuits while cranking?

Go to Step 3 If there was no

blinking light, Go

to Table A3.3

----------------------

If the test light

was on steady

(no blinking light)

Go to Step 4

3. At this point, the fuel control system, fuel delivery system,

and ignition system are OK.

Check For:

• Fouled spark plugs.

• Proper MAF sensor operation. If engine will start with

MAF sensor electrical connector disconnected, refer

Table A-6.1 in this Service Information.

• Proper TP sensor circuit operation. Use TECH 2 to

monitor TP sensor signal. If voltage is over 1.25 volts

with throttle closed, refer Table A-6.2 .

• Restricted exhaust system. Loosen front pipe from

exhaust manifold(s). If the engine will start, refer

Table A-13 .

• Improper engine coolant temperature (ECT) sensor

resistance. Refer DTC P0118 Diagnostic Aids to

check resistance of ECT sensor.

• Water or foreign material in fuel, or incorrect fuel.

• Spark plug wires crossed.

• Camshaft timing chain.

• Inadequate engine compression.

Is action complete?

Verify Repair

4. Check for a short to ground in injector circuit that caused

test light to stay "ON" steady.

Was a problem found?

Verify Repair Go to Step 5

5. Check resistance across each injector. Each injector

should be between the specified value.

Is each injector between the specified value?

11.4 - 12.6

ohms Go to step 6 Go to step 7

6. Replace PCM.

Refer to 6C1-3 Service Operations in this Service

Information, for PCM Programming and Security Link

procedure.

Is action complete?

Verify Repair

7. 1. Replace any injector that did not measure within the

specified value.

2. Retest beginning at Step 2.

Is action complete?

11.4 - 12.6

ohms Verify Repair

TABLE A-3.3 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

Figure 6C1-2A-29 – Injector Circuit

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. "NO LIGHT " indicates no PCM contro l of the inj ector. Fus e F34 supplies +12 vol ts to the inj ectors. Prob e both

terminals of one injector connector with a test light to ground. There should be a light on only one terminal,

confirming ignition voltage to one terminal, but not both.

3. The PCM injector control c irc uit ma y be open. Reco nnect the injector s. Using a tes t light conn ected to groun d,

check for a lig ht at the PC M connec tor term inals. A l ight at th is point indicat es that injector c ontrol cir cuit is not

"open." The voltage to light that test light comes from circuit 639, through t he injector windings, and cont inues

through the injector control circuit to PCM connector terminals.

5. During this test step TECH 2 should displa y the crank ing RPM. If RPM disp lay remains at zero (0) there is no

crankshaft reference pulses.

8. There is no terminal identification on the relay connector socket, but the relay itself has terminal numbers.

Make certain the correct relay connector socket terminal (NOT the relay) is being probed.

A84 V6 – X1 A84 V6 – X2 A84 V6 – X3

X4 (Part of X100) L2

Figure 6C1-2A-30

TABLE A-3.3 V6 PCM - ENGINE CRANKS BUT WILL NOT RUN

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. • From Table A-3.2

1. Ignition "OFF"

2. Disconnect injector connectors.

3. Ignition "ON," engine stopped.

4. Probe each terminal of each injector harness

connector with a test light to ground.

Is the test light "ON" at one terminal of each injector

connector?

Go to Step 3 If

the test light was

"ON" at both

terminals, repair

short to voltage

on injector circuit.

----------------------

there was no

light "ON", Go to

Step 7

3. 1. Ignition "OFF".

2. Reconnect injectors.

3. Ignition "ON".

4. Backprobe PCM injector control terminals with a test

light connected to ground.

Is test light "ON" at each terminal?

Go to Step 4 Go to Step 12

4. 1. Ignition "ON".

2. With TECH 2, monitor TP sensor signal voltage.

Is voltage less than the specified value?

1.25 volts Go to Step 5 Go to

Table A-6.2

5. 1. Ignition "ON".

2. W ith TECH 2, monitor the RPM signal while cranking

the engine.

Is there an RPM signal?

Go to Step 6 Go to DTC

P1372 Table.

6. Replace PCM.

Refer to 6C1-3 SERVICE OPERATIONS, for PCM

Programming and Security Link procedure.

Is action complete?

Verify Repair

7. 1. Ignition "OFF".

2. Disconnect EFI relay, R4.

3. Ignition "ON".

4. Probe EFI relay harness connector terminal X4 30

and terminal X4 85 with a test light connected to

ground.

Is the test light "ON" at both circuits?

Go to Step 8 Go to Step 13

8. 1. Ignition "OFF".

2. Disconnect EFI relay, R4.

3. With test light connected to 12 volts, probe relay

harness terminal ground circuit X4-86 of EFI relay.

Is test light "ON"?

Go to Step 9 Go to Step 14

STEP ACTION VALUE YES NO

9. Check injector fuse F34 for an open.

Was a problem found? Go to step 15 Go to Step 10

10. Check for an open in injector power circuit from fuse F34

to each injector connector term inal X1-1.

Was a problem found?

Verify Repair Go to Step 11

11. Replace EFI relay.

Is action complete? Verify Repair

12. Repair open injector control circuit that did not light test

light.

Is action complete?

Verify Repair

13. Check fuses and repair circuit that did not turn

"ON" test light.

Is action complete?

Verify Repair

14. Repair ground circuit to EFI relay.

Is action complete? Verify Repair

15. Repair short to ground in fuse circuit.

Replace fuse.

Is action complete?

Verify Repair

TABLE A- 4.0 V6 PCM - STARTER CRANKING CIRCUIT

Figure 6C1-2A-31 – Starter Cranking Circuit

CIRCUIT DESCRIPTION

When the ignition is turned to the "ON" position, battery power is supplied from a fusible link to the Start Relay

term inal X1- 30. As the igni tion s witch is turned to t he ST ART position, p ower is s upplie d to the Star t Rela y ter m inal

X1-85. The PCM supplies the ground signal needed to energise the Start Relay which allows power to the starter

motor.

W hen the ignition is tur ned “ON”, the PCM will the n loo k f or the proper T heft Deterr ent signal s ent from the BCM. If

the PCM has determined that the proper Theft Deterrent signal is present, the PCM will allow the vehicle to crank. If

the PCM determines that an improper Theft Deterrent signal was sent from the BCM, or no Theft Deterrent signal

was sent, the PCM will n ot suppl y a ground s ignal f rom the PCM term inal to the Start Rela y terminal X 1-86. W hen

the Start Re lay receives th is ground signa l from the PCM, the re lay will be ener gised, allowing th e starter motor to

operate. This removed ground signal to the Start Relay will cause the vehicle not to crank.

If there is a problem with the Theft Deterrent signal from the BCM to the PCM, DTC P1255 will set.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. This step check s to see if DTC P1255 is set. T his DTC c ould preve nt the veh icle fr om crank ing. This s tep als o

verifies that if a PCM was replaced, that the Security Link procedure was performed.

3. This step checks to see if power is being applied to the starter motor. If test light illuminates, the problem is with

the starter motor.

11. This step checks the adjustment of the Neutral start switch.

Figure 6C1-2A-32

TABLE A-4.0 V6 PCM - STARTER CRANKING CIRCUIT

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. 1. Install TECH 2.

2. Ignition “ON” engine “OFF”.

Does TECH 2 display “Theft Status” as “Start”?

Go to Step 3 Refer to 12J

BCM

DIAGNOSIS

3. 1. Ignition OFF.

2. Using a test light, probe the starter solenoid terminal

X1-A with test light connect ed to ground.

3. Have a helper turn the ignition switch to the START

position, note the test light.

Does the test light illuminate when the ignition switch is

turned to the START position?

Refer to 6D1-2

Starting System -

Go to Step 4

4. 1. Remove the start relay, R1.

2. W ith a test light connected to ground probe the start

relay harness terminal X1-30.

Does the test light illuminate?

Go to Step 5 Go to Step 15

5. 1. With the start relay still removed and the test light

connected to ground, probe the start relay harness

terminal X1-85.

2. Turn the ignition to the START position.

Did the test light illuminate?

Go to Step 7 Go to Step 14

6. Check for an open circuit between the starter solenoid

connector terminal X1-A and the Start Relay connector

terminal X1-87.

Was a problem found?

Verify Repair Go to Step 8

7. 1. Ignition OFF.

2. Remove the Start Relay.

3. Connect a test light between the relay harness

terminal X1-85 and termina l X1-86.

4. Turn the ignition switch to the START position.

Does the test light illuminate when the ignition switch is

turned to the START position?

Go to Step 6 Go to Step 9

8. Replace the Start Relay.

Is the action complete? Verify Repair

9. Is the vehicle equipped with an automatic transmission? Go to Step 10 Go to Step 16

10. 1. Ignition ON engine OFF.

2. With a test light connected to B+, probe terminal

X1-G at the neutral start switch.

Did the test light illuminate?

Go to Step 11 Go to Step 12

STEP ACTION VALUE YES NO

11. 1. Disconnect the neutral start switch connector A83.

2. Connect a fused jumper wire between A83 terminals

X1-E and X1-G.

3. Connect a test light between start relay harness

connector terminals X1-85 and X1-86.

4. Turn the ignition to the START position.

Did the test light illuminate when the ignition was turned

to the START position?

Go to Step 17 Go to Step 18

12. Check for open in circuit 275 from the neutral start switch

connector term inal X1-G to the PCM terminal X1-A8.

Was a problem found?

Verify Repair Go to Step 19

13. Repair the open or short to ground in the faulty circuit.

Replace the fusi ble lin k or the fuse as necessary .

Is the action complete?

Verify Repair

14. Repair the open in the cranking circuit from the ignition

switch or faulty ignition switch.

Is the action complete?

Verify Repair

15. Check for an open circuit 342 including the fusible link

F105.

Was an open circuit found?

Go to step 13

16. Repair the open in circuit 434, including PCM for correct

terminal retention.

Was an open circuit found?

Verify Repair Go to step 19

17. Check adjustment of neutral start switch. If adjustment is

OK replace switch. Verify Repair

18. Check for open in circuit 434 between neutral start switch

connector term inal X1-E and start relay connector X1-86.

Was an open circuit found?

Verify Repair

19. Replace PCM.

Refer 6C1-3 SERVICE OPERATIONS for PCM

Programming and Security Link procedure.

Is action complete?

Verify Repair

TABLE A-4.1 V6 PCM - FUEL PUMP ELECTRICAL CIRCUIT

Figure 6C1-2A-33 - Fuel Pump Electrical Circuit

CIRCUIT DESCRIPTION

When the ignition switch is turned "ON," the Powertrain Control Module (PCM) energises its Fuel Pump Relay

control output. It will provide +12 volts to the Fuel Pump Relay, as long as the engine is cranking or running, and

the PCM is receiving crankshaft reference input signal pulses.

If there are no crankshaft reference pulses (ignition "ON," engine stopped - or - engine stalled), the PCM will shut

"OFF" the Fuel Pump Relay within 2 seconds.

• Improper electrical control of the pump will result in one or more of the following symptoms:

• Cranks, but won't run.

• Hard start.

• Cuts out, may feel like ignition problem.

• Excessive cranking time.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

3. If the fuse is blown, this test will check for short to ground on Fuel Pump power feed circuit. To prevent mis-

diagnosis, be sure Fuel Pump is disconnected and ignition is "OFF" before performing this test.

4. This checks to see if the cause of the blown fuse is a short to ground in the Fuel Pump Relay power feed

circuit.

8. Determines if the PCM and Fuel Pump Relay circuit are operating correctly. The PCM should turn "ON" the

Fuel Pump Relay.

- If test light stays "OFF," go to Table A-4.2

- If test light stays "ON," disconnect the Fuel Pump Relay. If the test light now stays "ON," repair short to voltage

on Fuel Pump power feed circuit, but if the light goes out, check for short to voltage on Fuel Pump Relay

control circuit. If no voltage on Fuel Pump Relay control circuit, replace relay.

10. This should turn "ON" the Fuel Pump if Fuel Pump power feed circuit wiring is OK. If the Fuel Pump runs

(Pump Runs? YES), the Fuel Pump electrical circuit is OK. Continue to Table A-4.3 to complete the testing of

the fuel delivery system.

14. The fuel pump is serviceable separate from the Modular Sender Assembly. Refer to Section 6C1-3 Service

Operations for replacement procedures.

A84 V6 – X1 A84 V6 – X2 A84 V6 – X3

M8 A47 X16 (Part of X100)

Figure 6C1-2A-34

TABLE A-4.1 V6 PCM - FUEL PUMP ELECTRICAL CIRCUIT

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. Check Fuel Pump fuse F28 in engine compartment fuse

and relay centre.

Is the Fuel Pump fuse blown?

Go to step 3 Go to step 8

3. 1. Ignition "OFF".

2. Disconnect Fuel Pump electrical connector M8 from

the fuel pump.

3. Remove the Fuel Pump Relay and probe the fuel

pump power feed circuit connector X16-3 with a test

light connected to B+.

Is the test light "ON"?

Go to Step 15 Go to step 4

4. 1. Ignition "OFF".

2. Reconnect Fuel Pump electrical connector.

3. Replace Fuel Pump fuse F28.

4. Ignition "ON".

5. Recheck fuse.

Is Fuel Pump fu se OK?

Problem is

intermittent.

Refer

Intermittents in

this Section

Go to step 5

5. Check for short to ground in fuel pump power feed circuit

120 at fuel pump relay connector terminal X16-5.

Was a problem found?

Verify Repair Go to step 6

6. Check Fuel Pump for internal short.

Was fuel pump shorted internally? Go to Step 14

7. Replace Fuel Pump Relay.

Is action complete? Verify Repair

8. 1. Ignition "OFF".

2. Disconnect Fuel Pump Relay, R16 from relay

housing.

3. With Fuel Pump Relay disconnected, probe relay

connector terminal X16-1 with test light connected to

ground.

4. Ignition "ON".

5. Using TECH 2, Command Fuel Pump "ON" and

"OFF".

Is test light "ON" and "OFF" when Fuel Pump is

commanded "ON" and "OFF"?

Go to Step 9 If Test

Light stays

"OFF", Go to

Table A-4.2 in

this Section

-----------------------

If Test Light stays

"ON",

Go to Step 16

STEP ACTION VALUE YES NO

9. 1. Ignition "OFF".

2. Fuel pump relay still disconnected.

3. Connect a test light between X16-1 and X16-2.

4. Ignition "ON".

5. Using TECH 2, Command Fuel Pump "ON" and

"OFF"

Is test light "ON" and "OFF" when Fuel Pump is

commanded "ON" and "OFF"?

Go to Step 10 Go to

Table A-4.2 in

this Section

10. 1. Ignition "OFF".

2. Fuel pump relay still disconnected.

3. Connect a fused jumper wire between X16-3 and

X16-5.

Is fuel pump running?

Go to Step 7 Go to Step 11

11. Check for faulty connect ion at Fuel Pump and relay .

Is connection faulty? Verify Repair Go to Step 12

12. Check for open in Fuel Pump power feed circuit 120.

Was a problem found? Verify Repair Go to Step 13

13. Check for open in Fuel Pump.

Is Fuel Pump open? Go to Step 14 Go to Step 17

14. Replace Fuel Pump.

Is action complete? Verify Repair

15. Repair short to ground in Fuel Pump power feed circuit

240.

Is repair complete?

Verify Repair

16. Repair short to voltage in circuit 465.

For vehicles equipped with Telematics check for short to

voltage in circuits 465 and 497.

Is action complete?

Verify Repair

17. Repair open in fuel pump ground circuit 650.

Is action complete? Verify Repair

TABLE A-4.2 V6 PCM - FUEL PUMP ELECTRICAL CIRCUIT

Figure 6C1-2A-35 - Fuel Pump Electrical Circuit

CIRCUIT DESCRIPTION

Relay connector has no terminal identification. See diagram below for terminal identification.

There are 3 basic circuits to any relay. They are:

LOAD - This is the device controlled by the relay. In this case, it is the fuel pump’s power feed circuit.

LINE - This is the voltage supply that will power the load whenever the relay switch contacts are closed. In this

case, it is the fused power circuit.

CONTROL - This is the circuitry that energises the small electromagnet windings in the relay, which causes the

switching contacts to change position. In this case, one side of the relay windings is simply grounded. The other

control circuit is the +12 volts supplied by the PCM whenever it wants the relay to be energised.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. This checks the ground circuit 550 to the relay windings, part of the relay's control circuitry (CONTROL).

3. This checks the fuel pump power supply circuit 240 to the relay switching contacts (LINE).

4. This checks for the relay control voltage supplied by the PCM to the relay (CONTROL).

5. At this poi nt, the 3 oth er circ uits to the re lay are OK. This chec k is to det ermine if the contac ts in the re lay will

close, a llo win g th e c urr ent t o pas s throu gh the s witch in g c ontac ts to the "lo ad " terminal of the r elay, which go es

to the fuel pump motor.

7. Note: Before performing this Test Step ensure that the Telematics Service Mode is enabled. Refer

Section 12K TELEMATICS. If the telematics module is not in service mode a battery disconnect alert will be

sent to Holden Assist when this connector is disconnected.

A84 V6 – X1 A84 V6 – X2 A84 V6 – X3

X16 (Part of X100)

Figure 6C1-2A-36

TABLE A-4.2 V6 PCM - FUEL PUMP ELECTRICAL CIRCUIT

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. • From Table A-4.1.

1. Ignition "ON", engine not running.

2. Disconnect fuel pump relay from relay housing.

3. With fuel pump relay disconnected, probe relay

connector X16-2 ground circuit 550 with a test light

connected to B+.

Is test light "ON"?

Go to Step 3 Go to step 12

3. Probe relay connector power feed circuit 240 at fuel

pump relay connector terminal X16-3 with test light

connected to ground.

Is test light "ON"?

Go to Step 4 Go to step 13

4. 1. Probe relay control circuit 465 at fuel pump relay

connector terminal X16-1 with test light to ground.

2. Ignition "ON".

3. Using TECH 2, Select Fuel Pump.

4. Command Fuel Pump "ON" and "OFF".

Is test light "ON" and "OFF", when Fuel Pump is

commanded "ON" and "OFF"?

Go to Step 5 For vehicles

equipped with

Telematics

Go to Step 7

For other

vehicles go to

Step 8

5. 1. Reconnect fuel pump relay.

2. Ignition "ON".

3. Using TECH 2, Select Fuel Pump.

4. Probe fuel pump relay connector X16-5 power feed

circuit 120 with test light to ground.

5. Command fuel pump "ON" and "OFF".

Is test light "ON" and "OFF", when Fuel Pump is

commanded "ON" and "OFF"?

Go to Step 6 Go to Step 9

6. Fuel Pump Relay is operating correctly.

Repair open in power feed circuit 120 from fuel pump

relay to fuel pump.

Is action complete?

Verify Repair

STEP ACTION VALUE YES NO

7. Note: Before performing this Test Step ensure that the

Telematics Service Mode is enabled. Refer Section 12K

TELEMATICS.

1. Disconnect the Telematics Module Connector A158.

2. Connect a fused jumper wire between connector

A158 terminals X1-18 and X1-19.

3. Probe relay control circuit 465 at fuel pump relay

connector terminal X16-1 with test light to ground.

4. Ignition "ON".

5. Using TECH 2, Select FUEL PUMP.

6. Command Fuel Pump "ON" and "OFF".

Is test light "ON" and "OFF", when Fuel Pump is

commanded "ON" and "OFF"?

Replace

Telematics

Module. Refer

12K Telematics.

Go to step 8

8. 1. Ignition "O FF".

2. Disconnect Fuel Pump Relay and PCM connectors.

3. Check for open in Fuel Pump Relay control circuits

465 and 497.

Was a problem found?

Verify Repair Go to Step 10

9. 1. Ignition "OFF"

2. Replace Fuel Pump Relay.

Will engine start?

Verify Repair Go to OBD

System Check

10. Check for short to ground in Fuel Pump Relay control

circuit.

Was a problem found?

Verify Repair Go to step 11

11. Replace PCM.

Refer to 6C1-3 SERVICE OPERATIONS, for PCM

Programming and Security Link procedure.

Is action complete?

Verify Repair

12. Repair open in relay ground circuit 550.

Is action complete? Verify Repair

13. Repair open in Fuel Pump power feed circuit 240.

Is action complete? Verify Repair

TABLE A-4.3 V6 PCM - FUEL DELIVERY SYSTEM

Figure 6C1-2A-37 V6 Fuel Delivery System

1. Fuel Rail

2. Fuel Injector (6 places)

3. Fuel Feed

4. Fuel Pressure Regulator

5. Fuel Return

6. Fuel Filter

7. Fuel Tank Vapour Line

8. Fuel tank

9. Modular Fuel Sender Assembly

Fuel Pressure Too LOW or Too HIGH or Pressure That Continues to Drop After The Ignition is Turned OFF Can

Cause The Following Driveability Complaints:

• Poor Idle Quality

• Exces sive Ex ha us t Odour

• Poor Fuel Economy

• Excessive Cranking Time

• Detonation

• Loss of Power

• DTC P0132 or P0152

• DTC P0131 or P0151

CIRCUIT DESCRIPTION

Fuel is drawn from the tank by the electric fuel p ump and is fed under pressure through a fuel filter and continues

on into the fuel rail and then is injected into the ports through the fuel injectors.

Fuel pressure in the system is governed by the fuel pressure regulator, in such a manner that a certain pressure

difference between fuel pressure and inlet manifold pressure is maintained. Excess fuel above the regulated

pressure is returned to the fuel tank by the pressure regulator and the fuel return line.

The fuel pump has a check valve to maintain pressure at the fuel rail after the pump stops running. The check valve

plays an im portant part in the f uel del iver y s ystem: to k eep the f uel ra il "char ged" with fue l after the pum p shuts off .

When the engine begins cranking to start, there is no delay before fuel injection begins, and quick starting is

ensured. The check valve is inside the fuel pump, and is not serviceable.

TEST DESCRIPTION

Number(s) below refer to step number(s) on the diagnostic Table.

2. T hese are elec trical s ystem check s , which m ust both be O K before an y further fuel deliv er y system check s can

be made. If either do not "pass," refer Table A-4.1, Fuel Pump Electrical Circuit .

3. This has eleven sequenced segments to follow in order. "1" and "2" is to reduce the residual pressure in the

lines bef ore opening the lin es. "6" is to purge any air f rom the lines after installing the g auge. It also serves to

cool the fuel rail for more accurate pressure testing if the engine is hot. "9" is to allow the PCM to "power

down," so the next time the ignition is turned "ON," the PCM will energise its Fuel Pump Relay control for 2

seconds. "10" and "11" indicate what the pressure should do when the ignition is turned "ON". There are two

things to note: (A) - pressure reading, and (B) - that the pressure does not continue to drop after the pump

stops running.

4. At this point, the regulated pressure should be within specification, and the pressure does not drop when the

pump stops running. This check is to see if the pressure regulator will modulate the regulated fuel pressure

when the vacuum signal to it changes. During normal engine operation, the regulated pressure can change,

based on inlet m anifo ld pres sure. W hen the m anifold pressure is at its lowest (engi ne idli ng), fue l pressur e will

be at its lowest regulated pressure. When inlet manifold pressure is at its highest (wide open throttle), regulated

fuel pressure will be at its highest regulated pressure.

TABLE A-4.3 V6 PCM FUEL DELIVERY SYSTEM

STEP ACTION VALUE YES NO

1. Was the "On-Board Diagnostic" (OBD) System Check

performed? Go to Step 2 Go to

OBD System

Check

2. 1. Ignition "O N".

2. Using TECH 2, Select FUEL PUMP .

3. Turn Fuel Pump "On" and "OFF".

4. Listen for Fuel Pump in fuel tank.

Does the fuel pump run when turned "ON" with TECH 2?

Go to Step 3 Go to

Table A-4.1

3. 1. Disable output test for Fuel Pump .

2. Turn ignition "OFF".

3. Remove Fuel Pump Relay from engine compartment

fuse and relay centre, then crank engine for 15

seconds to relieve any residual fuel pressure.

4. Connect Fuel Pressure Gauge, then reinstall fuel pump

relay.

5. Remove vacuum hose from fuel pressure regulator.

6. Ignition "ON",

7. Enable output test with TECH 2 for Fuel Pump and

allow pump to run for 15 seconds. This is to purge the

lines of any air before pressure testing.

8. Disable output test for Fuel Pump.

9. Ignition "OFF" for 10 seconds.

10. Observe fuel pressure when ignition is turned "ON".

11. Pressure should be within specified value and not

continue to drop (after a small amount) after pump

stops running.

Is fuel pressure at or between the specified value and

holding?

270 to 350

kPa

Go to Step 4 Go to

Table A-4.4

4. 1. Ignition "ON".

2. Enable output test with TECH 2 for fuel pump and note

fuel pressure.

3. Connect a hand vacuum pump to the fuel pressure

regulator vacuum fitting, and apply 38 cm Hg of

vacuum to the fuel pressure regulator.

4. Note fuel pressure with vacuum applied to regulator.

W hen vacuum is appl ied, is fue l press ure at l east spe cified

value difference than when no vacuum applied?

15 kPa Fuel supply

system OK.

Refit regulator

vacuum hose.

Go to Step 5

5. Replace fuel pressure regulator.

Is repair complete? Verify Repair

TABLE A-4.4 V6 PCM - FUEL DELIVERY SYSTEM

Figure 6C1-2A-38 V6 Fuel Delivery System