SECTION 9J1 - SRS CONTROL SYSTEM

Service Precaution

Diagnostic Information

Parts For Electrical Circuit

System Schematic

SRS Diagnostic System Check

Chart A SDM Integrity Check

Chart B “AIR BAG" Warning Lamp Comes

“ON" Steady

Chart C “AIR BAG" Warning Lamp Does

Not Comes “ON" Steady

DTC 15 Passenger Deployment Loop

Resistance High

DTC 16 Passenger Deployment Loop

Resistance Low

DTC 17 Passenger Deployment Loop

Open

DTC 18 Passenger Deployment Loop

Short To Ground

DTC 19 Passenger Deployment Loop

Short To Voltage

DTC 21 Driver Deployment Loop

Resistance High

DTC 22 Driver Deployment Loop

Resistance Low

DTC 24 Driver Deployment Loop

Short To Ground

DTC 25 Driver Deployment Loop

Short To Voltage

DTC 26 Driver Deployment Loop Open

DTC 51 Deployment Event Commanded

DTC 53 Deployment Commanded With

Deployment Loop Fault Or Energy Reserves

Out Of Range

DTC 61 Warning Lamp Circuit Failure

DTC 71 Internal SDM Fault

Service Precaution

WARNING: THIS VEHICLE HAS A SUPPLEMENTAL

RESTRAINT SYSTEM (SRS). REFER TO THE SRS

COMPONENT AND WIRING LOCATION VIEW IN

ORDER TO DETERMINE WHETHER YOU ARE

PERFORMING SERVICE ON OR NEAR THE SRS

COMPONENTS OR THE SRS WIRING. WHEN YOU

ARE PERFORMING SERVICE ON OR NEAR THE

SRS COMPONENTS OR THE SRS WIRING, REFER

TO THE SRS SERVICE INFORMATION. FAILURE TO

FOLLOW WARNINGS COULD RESULT IN POSSIBLE

AIR BAG DEPLOYMENT, PERSONAL INJURY, OR

OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.

CAUTION: Always use the correct fastener in the

proper location. When you replace a fastener, use

ONLY the exact part number for that application.

ISUZU will call out those fasteners that require a

replacement after removal. ISUZU will also call out

the fasteners that require thread lockers or thread

sealant. UNLESS OTHERWISE SPECIFIED, do not

use supplemental coatings (Paints, greases, or

other corrosion inhibito r s) on thr eaded fastener s or

fastener joint interfaces. Generally, such coatings

adversely affect the fastener torque and the joint

clamping force, and may damage the fastener.

When you install fasteners, use the correct

tightening sequence and specifications. Following

these instructions can help you avoid damage to

parts and systems.

Diagnostic Information

Diagnostic Procedures

WARNING: WHEN FASTENERS ARE REMOVED,

ALWAYS REINSTALL THEN AT THE SAME

LOCATION FROM WHICH THEY WERE REMOVED.

IF A FASTENER NEEDS TO BE ReplaceD, USE THE

CORRECT PART NUMBER FASTENER FOR THAT

APPLICATION. IF THE CORRECT PART NUMBER

FASTENER IS NOT AVAILABLE, A FASTENER OF

EQUAL SIZE AND STRENGTH (OR STRONGER)

MAY BE USED. FASTENERS THAT ARE NOT

REUSED, AND THOSE REQUIRING THREAD

LOCKING COMPOUND WILL BE CALLED OUT. THE

CORRECT TORQUE VALUE MUST BE USED WHEN

INSTALLING FASTENERS THAT REQUIRE IT. IF THE

ABOVE CONDITIONS ARE NOT FOLLOWED, PARTS

OR SYSTEM DAMAGE COULD RESULT.

WARNING: TO AVOID DEPLOYMENT WHEN

TROUBLESHOOTING THE SRS, DO NOT USE

ELECTRICAL TEST EQUIPMENT SUCH AS A

BATTERY–POWERED OR AC–POWERED

VOLTMETER, OHMMETER, ETC., OR ANY TYPE OF

ELECTRICAL EQUIPMENT OTHER THAN THAT

SPECIFIED IN THIS MANUAL. DO NOT USE A

NONPOWERED, PROBE–TYPE TESTER.

INSTRUCTIONS IN THIS MANUAL MUST BE

FOLLOWED CAREFULLY, OTHERWISE PERSONAL

INJURY MAY RESULT.

The diagnostic procedures used in this section are

designed to aid in finding and repairing SRS problems.

Outlined below are the steps to find and repair SRS

problems quickly and effectively. Failure to carefully

follow these procedures may result in extended

diagnostic time, incorrect diagnosis and incorrect parts

Replacement.

1. Perform The “SRS Diagnostic System Check."

The “Supplemental Restraint System (SRS)

Diagnostic System Check" should always be the

starting point of any SRS diagnostics. The “SRS

Diagnostic System Check" checks for proper “AIR

BAG" warning lamp operation and checks for SRS

trouble codes us ing both “Fla sh Code " a nd “Scan

Tool " Meth ods.

2. Refer To The Proper Diagnostic Chart As

Directed By The “SRS Diagnostic System

Check."

The “SRS Diagnostic System Check" will lead you

to the correct chart to diagnose any SRS prob lems.

Bypassing these procedures may result in extended

diagnostic time, incorrect diagnosis and incorrect

parts Replaceme nt.

3. Repeat the “SRS Diagnostic System Check"

After Any Repair Or Diagnostic Procedures Have

Been Performed.

Per for mi ng the “SRS Dia gnos ti c Sy st em C heck"

after all repair or diagnostic procedures will assure

that the repair has been made correctly and that no

other conditions exist.

Diagnostic Codes

The Sensing and Diagnostic Module (SDM) maintains a

history record of all diagnostic codes that have been

detected since the SRS codes were last cleared during

service.

1. Active Codes—Faults that are presently detected

this ignition cycle. Active codes are stored in

Random Access Memory (RAM).

2. History Codes—All faults detected since the last

time the history fault memory was cleared. History

codes are stored in Electronically Erasable

Programmable Read only Memory (EEPROM).

How To Read Trouble Codes

All codes (Active and history) can be read (or cleared)

by using a scan tool or equivalent.

If a Diagnostic Trouble Code (DTC) is not available,

have the vehi cle serviced by dealer.

How To Clear Trouble Codes

Trouble codes can only be cleared by using a scan tool.

If a scan tool is not available then inform the owner of

the stored codes and suggest that the codes are

cleared upon the next visit to a dealership.

Scan Tool Diagnostics

A scan tool can be used to read current and history

codes and to clear all history codes after a repair is

complete. The scan tool must be updated to

communicate with the SRS through a replaceable

cartridge for SRS diagnostics. To use the scan tool,

connect it to the Data Link Connector (DLC) and turn

the ignition s witch “ON". Then f ollow the manuf acturer's

directions for communication with the SRS. The scan

tool reads serial data from the Sensing and Diagnostic

Module (SDM) “Serial Data" output (terminal 24) to the

DLC.

Basic Knowledge Required

Before using this section of the Service Manual, there is

some basic knowledge which will be required. Without

this knowledge, you will have trouble using the

diagnostic procedures in this section. Use care to

prevent harm or unwanted deployment. Read all

cautions in the service manual and on warning labels

attached to SRS components.

Basic Electrical Circuits

You should understand the basic theory of electricity

including series and parallel circuits, and understand

the voltage drops across series resistors. You should

know the meaning of voltage (volts), current (amps),

and resistance (ohms). You should understand what

happens in a circuit with an open or a shorted wire. You

should be able to read and understand a wiring

diagram.

“Flash Code" Diagnostics

Flash code diagnostics can be used to read current

codes and to determine if history codes are present but

cannot be used to clear codes or read history codes.

Flash code diagnostics is enabled by grounding by

terminal 13 shorting to terminal 4 of the DLC with the

ignition switch “ON". Grounding terminal 13 of the DLC

pulls the “Diagnostics Request" input (Terminal 1) of the

SDM low and signals the SDM to enter the flash code

diagnostic display mode.

The SDM displays the trouble codes by flashing the

warning lamp . Each code that is display ed will consist of

a number of flashes which represents the tens digit, a

1.2 second pause, following by a number of flashes

which represents the ones digit of the code. Each code

is display ed one time before moving on to the next code.

After all of the codes have been displayed, the entire

code sequence will continually by repeated until ground

is removed from terminal 13 of the DLC.

Two special codes exist when reading in the flash code

mode (Flash Code 12 and Flash Code 13). “Flash

Code 12" will always be the first code displayed when

the flash code mode is enab led Code 12 is not an

indication of a SRS problem but an indication that the

flash code mode has been enabled. If there are no

current or history codes present, the SDM will display

code 12 until ground is removed from the DLC at

terminal 13. “Flash Code 13" will be displayed if there

are history codes. To read the h istory codes, a scan

tool must be used.

Parts For Electrical Circuit

Wiring

Wire Color

D08RX174

Legend

EndOFCallout

All wires have color-coded insulation.

Wires belonging to a system’s main harness wil have a

single color. Wires belonging to a system’s sub-circuits

will have a colored stripe. Striped wires use the following

code to show wire size and colors.

D08RX175

Abbreviations are used to indicate wire color within a

circuit diagram.

Refer to the following table.

Wire Color Coding

Distinction of Circuit by Wire Base Color

(1) Colored Stripe

(2) Single Color

Color-coding Meaning Color-coding Meaning

BBlackBRBrown

W White LG Light green

R Red GR Grey

G Green P Pink

Y Yellow LB Light blue

LBlueVViolet

OOrange

Base

color Circuits Base

color Circuits

B Starter circuit and grounding circuit Y Instrument circuit

W Chargi ng ci rcui t L, O, BR,

LG, G R, P,

SB, V Other circuitR Lighting circuit

G Signal circuits

System Schematic

D09RX002

SRS Diagnostic System Check

The diagnostic procedures used in this section are

designed to find and repair Supplemental Restraint

System (SRS) malfunctions. To get the best results, it

is important to use the diagnostic charts and follow the

sequence listed below:

A Perform the “SRS Diagnostic System Check."

The “SRS Diagnostic System Check" must be the

starting point of any SRS diagnostics. The “SRS

Diagnostic System Check" checks for proper “AIR

BAG" warning lamp operation, the ability of the

Sensing and Diagnostic Module (SDM) to

communicate through the “Serial Data" line and

whether SRS diagnostic trouble codes exist.

B Refer to the proper diagnostic chart as directed by

the “SRS Diagnostic System Check."

The “SRS Diagnostic System Check" will lead you

to the correct chart to diagnose any SRS

malfunctions. Bypassing these procedures may

result in extended diagnostic time, incorrect

diagnosis and incorrect parts replacement.

C Repeat the “SRS Diagnostic System Check" after

any repair or diagnostic procedures have been

performed.

Performing the “SRS Diagnostic System Check"

after all repair or diagnostic procedures will ensure

that the repair has been made correctly and that no

other malfunctions exist

Circuit De sc r i p t i o n

When the ignition switch is first turned “ON", “ignition 1"

voltage is applied from the “SRS" fuse to the SDM at the

“ignition 1" input terminals “12". The SDM responds by

flashing the “AIR BAG" warning lamp sev en times while

performi ng test s on the S RS.

Notes On System Check Chart:

Number(s) below refer to step number(s) on the

“Supplemental Restraint System Diagnostic System

Check" chart.

1. The “AIR BAG" warning lamp should flash seven

times after ignition is first turned “ON."

2. After the “AIR BAG" w arning lamp flashes seven

times, it should turn “OFF."

3. Improper operation of the “AIR BAG" warning lamp is

indicated. This test differentiates a warning lamp

stays “ON" condition from a warning lamp does not

come “ON" condition.

4. This test checks f or the proper operation of the “Serial

Data" line. This test will also determine whether

history diagnostic trouble codes are stored and, if so ,

identify them.

5. This test checks for proper operation of the “Serial

Data" line. This test will also identify the stored

diagnostic trouble codes and whether they are

current or history.

Diagnostic Aids:

The order in which diagnostic trouble codes are

diagnosed is very important. Failure to diagnose the

diagnostic trouble codes in the order specified may

result in extended diagnostic time, incorrect diagnosis

and incorrect parts Replacement.

SRS Diagnostic System Check

Step Action Yes No

1 Note the “AIR BAG" warning lamp when ignition switch is turned

“ON."

Does the “AIR BAG" warning lamp flash seven (7) times? Go to Step 2 Go to Step 3

2 Note the “AIR BAG" warning lamp after it flashed 7 times.

Does the “AIR BAG" warning lamp go “OFF"? Go to Step 4 Go to Step 5

3 Note the “AIR BAG" warning lamp when ignition switch is turned

“ON."

Does the “AIR BAG" warning lamp come “ON" steady? Go to Chart B. Go to Chart C.

4 1. Ignition switch “OFF."

2. Connect a scan tool to data link connector.

3. Follow direction given in the scan tool instruction manual.

4. Ignition switch “ON."

5. Request the SRS diagnostic trouble code display recode all

history diagnostic trouble code(s) specify as such, on repair

order.

Is diagnostic trouble code(s) displayed?

Ignition switch

“OFF."

When DTC 71

is set, go to

DTC 71 chart.

For all other

history codes

refer to

“Diagnostics

Aids" for that

specific DTC.

A history DTC

indicates the

malfunction has

been repaired

or is

intermittent.

SRS is

functional and

free of

malfunc ti ons,

no furt her

diagnosis is

required.

If scan tool

indicates “No

Data Received,"

refer to chassis

electrical

section.

5 1. Ignition switch “OFF."

2. Connect a scan tool to data link connector.

3. Follow directions as given in the scan tool instruction manual.

4. Ignition switch “ON."

5. Request the SRS diagnostic trouble code display, recode all

diagnostic trouble code(s), specifying as current or history on

repair order.

Is diagnostic trouble code(s) displayed?

Ignition switch

“OFF."

When DTC 53

is set, go to

DTC 53 chart.

When DTC 51

is set, go to

DTC 51 chart.

When DTC 19

is set, go to

DTC 19 chart.

When DTC 25

is set, go to

DTC 25 chart.

Diagnose

remaining

current DTCs

from lowest to

highest.

When only

history DTCs

e xist, Refer to

“Diagnostics

Aids" for that

specific DTC.

A history DTC

indicates the

malfunction has

been repaired

or is

intermittent.

If scan tool

indicates “No Data

Receiv ed," ref er to

chassis electrical

section.

Step Action Yes No

Chart A SDM Integrity Check

D09RX002

Circuit Description:

When the Sensing and Diagnostic Module (SDM)

recognizes “ignition 1" v oltage, applied to terminals “12",

is greater than 9 volts, the “AIR BAG" warning lamp is

flashed 7 times to verify operation. At this time the

SDM performs “Turn–ON" tests f ollowed by “Continuous

Monitoring" tests. When a malfunction is detected, the

SDM sets a current diagnostic trouble code and

illuminates the “AIR BAG" w arning lamp. The SDM will

clear current diagnostic trouble codes and move them to

a history file when the malfunction is no longer detected

and/or the ignition switch is cycled, ex cept for

Diagnostic Trouble Codes (DTCs) 51, 53 and 71. DTC

71 can only be cleared using a scan tool “Clear Codes"

command in case that the malfunction on DTC 71 has

been solved and no DTCs 51 and 53 were remained.

DTCs 51, 53 and 71 can not be cleared after a “Clear

Codes" command is issued.

Chart Test Description:

Number(s) below refer to step number(s) on the

diagno sti c ch art:

1. This test confirms a current malfunction. If no current

malfunction is occurring (history DTC set) the

“Diagnostic Aids" for the appropriate diagnostic

trouble code should be ref erenced. The SDM should

not be replaced for a history diagnostic troub le code.

2. This test checks for a malfunction introduced into the

SRS during the diagnostic process. It is extremely

unlikely that a malfunctioning SDM would cause a

new malfunction to occur during the diagnostic

process.

3. When all circuitry outside the SDM has been f ound to

operate properly, as indicated by the appropriate

diagnostic chart, then and only then should the SDM

be replaced.

Chart A SDM Integrity Check

WARNING: DURING SERVICE PROCEDURES. BE

VER Y CAREFUL WHEN HANDLING A SENSING AND

DIAGNOSTIC MODULE (SDM). NEVER STRIKE OR

J AR TH E SDM. NEVER POWER UP THE SRS WHEN

THE SDM IS NOT RIGIDLY ATTACHED TO THE

VEHICLE. ALL SDM AND MOUNTING BRACKET

FASTENERS MUST BE CAREFULLY T ORQUED AND

THE ARROW MUST BE POINTING TOWARD THE

FRONT OF THE VEHICLE TO ENSURE PROPER

OPERATION OF THE SRS. THE SDM COULD BE

ACTIVATED WHEN POWERED WHILE NOT RIGIDLY

ATTACHED T O THE VEHICLE WHICH COULD

CAUSE DEPLOYMENT AND RESULT IN PERSONAL

INJURY.

Step Action Yes No

1 1. This chart assumes that the “SRS Diagnostic System Chec k"

and either a symptom chart or a diagnostic trouble code chart

diagnosis hav e been perf ormed When all circuitry outside the

SDM has been f ound to operate properly, as indicated by the

appropriate diagnostic chart, and the symptom or DTC

remains current, the following diagnostic procedures must be

performed to verify the need for SDM Replacement.

2. Ignition switch “OFF."

3. Reconnect all SRS components, ensure all components are

properly mounted.

4. Ensure the ignition switch has been “OFF" for at least 15

seconds.

5. Note “AIR BAG" warning lamp as ignition switch is turned

“ON."

Does warning lamp flash 7 times then go “OFF"?

The symptom

or DTC is no

longer

occurring.

Clear SRS

diagnostic

trouble codes.

Repeat the

“SRS

Diagnostic

System Check." Go to Step 2

2 Using a scan tool, request diagnostic trouble code display.

Is the same symptom or DTC occurring as was when the “SRS

Diagnostic System Check " was first performed?

Ignition switch

“OFF."

Go to the

appropriate

chart for the

indicated

malfunction. Go to Step 3

3 1. Clear “SRS Diagnostic Trouble Codes."

2. Ignition switch “OFF" for at least two minutes.

3. Note “AIR BAG" warning lamp as ignition switch is turned

“ON."

Does warning lamp flash 7 times then go “OFF"?

SRS is

functional and

free of

malfunctions.

No further

diagnosis is

required.

Go to Step 4

Ignition switch

“OFF."

Replace SDM.

Go to Step 4

4 Reconnect all SRS components, ensure all components are

proper l y mou nted .

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 4

Chart B “AIR BAG" Warning Lamp Comes “ON" Steady

D09RX002

Circuit Description:

When the ignition switch is first turned “ON", “ignition 1"

v oltage is applied from the “METER” fuse to “AIR BAG",

warning lamp which is connected to “Supplemental

Restraint System (SRS) warning lamp", terminal “7".

The “SRS" fuses apply system voltage to the “ignition

1" inputs, terminals “12". The Sensing and Diagnostic

Module (SDM) responds by flashing the “AIR BAG"

warning lamp 7 times. If “ignition 1" voltage is less than

9 volts, the “AIR BAG" warning lamp will come “ON"

solid with no DTCs set.

Chart Test Description:

Number (s) below refer to step number (s) on the

diagnostic chart.

2. This test checks for an open in the “ignition 1" circuit

to the SDM.

3. This test checks for the voltage of “ignition 1."

4. This test determines whether the malfunction is a

short to ground in Circuit IB04 – GREEN.

Chart B “AIR BAG" Warning Lamp Comes “ON" Steady

Step Action Yes No

1 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Connect scan tool to data link connector , F ollow directions as

given in the scan tool instr uc tio n m anual.

4. Ignition switch “ON."

5. Request SRS diagnostic trouble code displa y.

Does scan tool indicate “No Data Received"? Go to Step 2 Go to Step 3

2 1. Ignition switch “OFF."

2. Inspect SDM harness connector connection to SDM.

Is it securely connected to the SDM? Ignition switch

“OFF."

Replace SDM .

Go to Step 5

Connect SDM

securely to de–

activate

shorting clip in

SDM harness

connector.

Go to Step 5

3 Using scan tool, request SRS data list.

Is “ignition" more than 9 volts?

Go to Step 4

Ignition switch

“OFF."

Replace SDM.

Go to Step 5

4 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag assemblies.

Yellow 2–pin connectors located at base of steering column

and behind the glove box assembly.

3. Disconnect SDM.

4. Measure resistance from SDM harness connector terminal

“6" to ground.

Does DVM display “0L" (infinite) ? Go to Chart A.

Replace SRS

harness.

Go to Step 5

5 Reconnect all SRS components, ensure all components are

proper l y mou nted .

Was this step finished?

Repeat the

“SRS

Diagnostic

System Check." Go to Step 5

Chart C “AIR BAG" Warning Lamp Does Not Comes “ON" Steady

D09RX002

Circuit Description:

When the ignition switch is first turned “ON", “ignition 1"

voltage is applied from the “METER" fuse to the “AIR

BA G" warning lamp which is connected to

“Supplemental Restraint System (SRS) warning lamp",

terminal “7". The “SRS" fuse apply system voltage to

the “ignition 1" inputs, terminals “12". The Sensing and

Diagnostic Module (SDM) responds b y flashing the “AIR

BA G" warning lamp seven times. If “ignition 1" voltage

is more than 16 volts, the “AIR BAG" warning lamp will

be still “OFF" solid with no DTCs set.

Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

1. This test decides whether power is available to SDM

warning lamp power feed circuit.

2. This test determines whether the v oltage is present in

the warning lamp circuit.

3. This test determines if the malfunction is in the

instrument cluster.

4. This test checks for open in the warning lamp

circuitry.

5. This test isolates the IB04–GREEN circuit and checks

for a short in the IB04–GREEN circuit to B+.

8. This test checks for a short from the SDM warning

lamp power feed circuit to ground.

9. This test determines whether the short to ground is

due to a short in the wiring.

Chart C “AIR BAG" Warning Lamp Does Not Come s “ON" Steady

Step Action Yes No

1 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Remove and inspect “METER" fuse to the “AIR BAG"

warni ng lam p.

Is fuse good? Go to Step 2 Go to Step 7

2 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag assemblies.

Yellow 2–pin connectors located at base of steering column

and behind the glove box assembly.

3. Disconnect SDM.

4. Ignition switch “ON."

5. Measure voltage on SDM harness connector from terminal

“7" to terminal “6" (ground).

Is system voltage present on terminal “7"? Go to Step 4 Go to Step 3

3 1. Ignition switch “OFF."

2. Remove instrument meter cluster.

3. Check for proper connection to instrument cluster at IB04–

GRN terminal.

4. If OK, then remove and inspect “AIR BAG" bulb.

Is bulb good? Go to Step 5 Replace bulb.

Go to Step 6

4 1. Ignition switch “OFF."

2. Disconnect instrument meter cluster harness connector.

3. Ignition switch “ON."

4. Measure voltage on SDM harness connector from terminal

“7" to terminal “6" (ground).

Is voltage 1 volt or less? Go to Chart A.

Replace SRS

harness.

Go to Step 6

5 1. Install bulb.

2. Measure resistance from instrument meter cluster harness

connector IB04–GRN terminal to SDM harness connector

ter m inal “7".

Is resistance 5.0 ohms or less?

Service

instrument

meter clus ter.

Go to Step 6

Replace SRS

harness.

Go to Step 6

6 Reconnect all SRS components, ensure all components are

proper l y mou nted .

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 6

7 Were you sent here from chart C? Go to Step 8 Go to Step 1

8 1. Replace “METER" fuse.

2. Ignition switch “ON" wait 10 seconds then ignition switch

“OFF."

3. Remove and inspect “METER" fuse.

Is fuse good?

Install “METER"

fuse.

Go to Step 10 Go to Step 9

9 1. Disconnect SRS coil and passenger air bag assemblies.

Yellow 2–pin connectors located at base of steering column

and behind the glove box assembly.

2. Disconnect SDM.

3. Replace “METER" fuse.

4. Ignition switch “ON" wait to 10 seconds.

5. Ignition switch “OFF".

6. Remove and inspection “METER" fuse.

Is fuse good?

Install “METER"

fuse.

Go to Chart A.

Replace SRS

harness.

Replace

“METER" fuse.

Go to Step 10

10 Reconnect all SRS components, ensure all components are

proper l y mou nted .

Was this step finished?

Repeat the

“SRS

Diagnostic

System Check." Go to Step 10

Step Action Yes No

DTC 15 Passenger Deployment Loop Resistance High

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges. The SDM then

proceeds with the “Resistance Measurement Test".

“Passenger Bag Low" terminal “16" is grounded

through a resister and the passenger current source

connected to “Passenger Bag High" terminal “15" allows

a known amount of current to flow. By monitoring the

voltage difference between “Passenger Bag High" and

“Passenger Bag Low" the SDM calculates the

combined resistance of the passenger air bag

assembly, harness wiring Circuits(CKTs) IB07–

YELLOW/GREEN and IB08–YELLOW/RED connector

terminal contact.

DTC Will Set When:

The combined resistance of the passenger air bag

assembly, harness wiring CKTs IB07–YELLOW/GREEN

and IB08–YELLOW/RED, and connector terminal

conta ct is abov e a spec ified v alue . This test is run once

each ignition cycle during the “Resistance

Measurement Test" when:

1. No “higher priority faults" are detected during “Turn–

ON."

2. “Ignition 1" voltage is in the specified value.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

The ignition switch is turned “OFF."

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

3. This test verifies proper connection of the yellow 2–

pin connector.

4. This test checks for proper contact and/or corrosion

of the yellow 2–pin connector terminals.

5. The test checks for a malfunctioning passenger air

bag assembly.

6. This test determines whether the malfunction is due

to high resistance in the wiring.

Diagnostic Aids:

An intermittent condition is likely to be caused by a poor

connection at the passenger air bag assembly harness

connector terminals “1" and “2", SDM terminal “15" and

“16", or a poor wire to terminal connection in

Circuits(CKTs) IB07–YELLOW/GREEN and IB08–

YELLOW/RED. This test for this diagnostic trouble

code is only run while the “AIR BAG" warning lamp is

performing the bulb check, unless Diagnostic Trouble

Code (DTC) 17 or DTC 26 is detected. When a scan

tool “Clear Codes" command is issued and the

malfunction is still present, the DTC will not reappear

until the next ignition cycle.

DTC 15 Passenger Deployment Loop Resistance High

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Use scan tool data list function, read and record the

passenger deployment loop resistance.

Is passenger resist more than 2.9 ohms? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Make sure the passenger air bag assembly yellow 2–pin

connector located behind the glove box assembly is seated

properly.

Is the yellow 2–pin connector connected properly?

Go to Step 4

Seat passenger

air bag

assembly

yellow 2–pin

connector

properly.

Go to Step 7

4 1. Disconnect and inspect the passenger air bag assemb ly

yellow 2–pin connector located behind the glove box

assembly.

2. If OK, reconnect the passenger air bag assembly 2–pin

connector.

3. Ignition switch “ON."

Is DTC 15 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 7

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag 2–pin connectors

located at the base of the steering column and behind the

glove box assembly.

3. Connect 5–8840–2421–0 SRS driver / passenger load tool

and appropriate adapters to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 15 current? Go to Step 6

Ignition switch

“OFF."

Replace the

passenger air

bag assembly.

Go to Step 7

6 1. Ignition switch “OFF."

2. There has been an increase in the total circuit resistance of

the passenger inflator deployment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB07–YEL/GRN and IB08–YEL/RED, and

SDM connector terminal “15" and “16" to locate the root

cause.

Was a fault found?

Replace SRS

harness.

Go to Step 7 Go to Chart A.

7 1. Reconnect all components ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 7

DTC 16 Passenger Deployment Loop Resistance Low

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges. The SDM then

proceeds with the “Resistance Measurement Test".

“P assenger Bag Low" terminal “16" is grounded through

a resistor and the passenger current source connected

to “Passenger Bag High" terminal “15" allows a known

amount of current to flow. By monitoring the voltage

difference between “Passenger Bag High" and

“Passenger Bag Low", the SDM calculates the

combined resistance of the passenger air bag

assembly, harness wiring Circuits(CKTs) IB07–

YELLOW/GREEN and IB08–YELLOW/RED connector

terminal contact.

DTC Will Set When:

The combined resistance of the passenger air bag

assemb ly, harness wiring CKTs IB07–YELLOW/

GREEN and IB08–YELLOW/RED, and connector

terminal contact is abov e a specified v alue. This test is

run once each ignition cycle during the “Resistance

Measurement Test" when:

1. No “higher priority faults" are detected during “Turn–

ON",

2. “Ignition 1" voltage is in the specified value.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

The ignition switch is turned “OFF."

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

3. This test verifies connection of the y ellow 2–pin

connector.

4. This test cheeks for proper operation of the shorting

clip in the yellow 2–pin connector.

5. The test checks for a malfunction passenger air bag

assembly.

6. This test determines whether the malfunctioning is

due to shorting in the wiring.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

between Circuits(CKTs) IB07–YELLOW/GREEN and

IB08–YELLOW/RED, or a malfunctioning shorting clip

on the passenger air bag assembly which would require

replacement of the air bag assembly. The test f or this

diagnostic trouble code is only run while “AIR BAG"

warning lamp is performing the bulb check, unless

Diagnosti c Tr ouble Code (DTC) 17 or DTC 26 is

detected. When a scan tool “Clear Codes" command is

issued and the malfunction is still present, the DTC will

not reappear until the next ignition cycle.

DTC 16 Passenger Deployment Loop Resistance Low

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Using scan tool data list function, read and record the

passenger deployment loop resistance.

Is passenger resist. less than 1.4 ohms? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Make sure the passenger air bag assembly yellow 2–pin

connector located behind the glove box assembly is seated

properly.

Is the yellow 2–pin connector connected properly?

Go to Step 4

Seat passenger

air bag

assembly

yellow 2–pin

connector

properly.

Go to Step 7

4 1. Disconnect and inspect the passenger air bag assemb ly

yellow 2–pin connector located behind the glove box

assembly.

2. If OK, reconnect the passenger air bag assembly 2–pin

connector.

3. Ignition switch “ON."

Is DTC 16 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 7

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag 2–pin connectors

located at the base of the steering column and behind the

glove box assembly.

3. Connect 5–8840–2421–0 SRS driver / passenger load tool

and appropriate adapters to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 16 current? Go to Step 6.

Ignition switch

“OFF."

Replace the

passenger air

bag assembly.

Go to Step 7

6 1. Ignition switch “OFF."

2. There has been a decrease in the total circuit resistance of

the passenger inflator deployment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB07–YEL/GRN and IB08–YEL/RED, and

SDM connector terminal “15" and “16" to locate the root

cause.

Was a fault found?

Replace SRS

harness.

Go to Step 7 Go to Chart A.

7 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 7

DTC 17 Passenger Deployment Loop Open

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges. During “Continuous

Monitoring" diagnostics, a fixed amount of current is

flowing in the deployment loop. This produces

proportional voltage drops in the loop. By monitoring

the voltage difference between “Passenger Bag High"

and “Passenger Bag Low", the SDM calculates the

combined resistance of the passenger air bag

assembly, harness wiring Circuits(CKTs) IB07–

YELLOW/GREEN and IB08– YELLOW/RED, and

connector terminal contact.

DTC Will Set When:

The voltage difference between “Passenger Bag High"

terminal “15" and “P assenger Bag Low" terminal “16" is

above or equal to a specified value for 500 milliseconds

during “Continuous Monitoring".

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

The voltage difference between “Passenger Bag High"

terminal “15" and “P assenger Bag Low" terminal “16" is

below a specified value for 500 milliseconds during

“Continuous Monitoring".

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

3. This test verifies proper connection of the yellow 2–

pin connector.

4. This test cheeks for proper contact and/or corrosion

of the shorting clip in the yellow 2–pin connector

terminals.

5. The test checks for a malfunctioning passenger air

bag assembly.

6. This test determines whether there is an open in the

wiring.

Diagnostic Aids:

An intermittent condition is likely to be caused by a poor

connection at the passenger air bag assembly harness

connector terminals “1" and “2," SDM terminals “15"

and “16," or an open in Circuits IB07–YELLO W/GREEN

and IB08–YELLOW/RED.

DTC 17 Passenger Deployment Loop Open

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Using scan tool data list function, read and record the

passenger differential voltage.

Is passenger differential voltage. more than 4.25 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Make sure the passenger air bag assembly yellow 2–pin

connector located behind the glove box assembly is seated

properly.

Is the yellow 2–pin connector connected properly?

Go to Step 4

Seat passenger

air bag

assembly

yellow 2–pin

connector

properly.

Go to Step 7

4 1. Disconnect and inspect the passenger air bag assemb ly

yellow 2–pin connector located behind the glove box

assembly.

2. If OK, reconnected the passenger air bag assembly yello w 2–

pin connector.

3. Ignition switch “ON."

Is DTC 17 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 7

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag assembly yellow

2–pin connectors located at the base of the steering column

and behind the glove box assembly.

3. Connect 5–8840–2421–0 SRS driver / passenger load tool

and appropriate adapters to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 17 current? Go to Step 6

Ignition switch

“OFF."

Replace the

passenger air

bag assembly.

Go to Step 7

6 1. Ignition switch “OFF."

2. There has been an open circuit in the passenger inflator

deployment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB07–YEL/GRN and IB08–YEL/RED, and

SDM connector terminal “15" and “16" to locate the root

cause.

Was a fault found?

Replace SRS

harness.

Go to Step 7 Go to Chart A.

7 1. Reconnect all components ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 7

DTC 18 Passenger Deployment Loop Short To Ground

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

The SDM monitors the voltages at “Driver Bag Low"

terminal “4" and “Passenger Bag Low" terminal “16" to

detect short to ground in the air bag assembly circuits.

DTC Will Set When:

Neither of the two air bag assemblies is open.

“Ignition 1" is within the normal operating v oltage range.

Once these conditions are met and the voltage at

“Passenger Bag Low" is below a specified value,

Diagnostic Trouble Code (DTC) 18 will set. This test is

run once each ignition cycle and “Continuous

Monitoring".

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

This malfunction is no longer occurring and the ignition

switch is turned “OFF".

DTC Chart Test Desc ription:

Number(s) below refer to circled number(s) on the

diagno sti c ch art:

2. This test determines whether the SDM is

malfunctioning.

3. This test isolates the malfunction to one side of the

passenger air bag assembly y ellow 2–pin connector

behind glove box compartment.

4. This test determines whether the malfunction is in

Circuit(CKT) IB07–YELLOW/GREEN.

5. This test determines whether the malfunction is in

CKT IB08–YEL LOW/RED.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

to ground in the passenger air bag assembly circuit.

Inspect CKTs IB07–YELLOW/GREEN and IB08–

YELLOW/RED carefully for cutting or chafing. If the

wiring pigtail of the passenger air bag assembly is

damaged, the component must be replaced.

DTC 18 Passenger Deployment Loop Short To Ground

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Connect scan tool data link connector. Follow directions as

given in the scan tool operator's manual.

4. Ignition switch “ON."

5. Read passenger sense LO.

Is passenger sense LO less than 1.5 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Disconnect passenger air bag assembly yellow 2–pin

connector behind the glove box assembly..

3. Leave driver air bag assembly connected.

Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to passenger air bag assembly

harness connector.

4. Ignition switch “ON."

Is DTC 18 current? Go to Step 4

Ignition switch

“OFF."

Replace

passenger air

bag assembly.

Go to Step 6

4 1. Ignition switch “OFF."

2. Disconnect SRS driver / passenger load tool.

3. Measure resistance on SDM harness connector from

terminal “15" to terminal “6" (ground).

Does DVM display “0L" (infinite)? Go to Step 5

Replace SRS

harness.

Go to Step 6

5 Measure resistance on SDM harness connector from terminal “6"

“16" to terminal (ground).

Does DVM display “0L" (infinite) ? Go to Chart A.

Replace SRS

harness.

Go to Step 6

6 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 6

DTC 19 Passenger Deployment Loop Short To Voltage

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

The SDM monitors the voltages at “Driver Bag Low"

terminal “4" and “Passenger Bag Low" terminal “16" to

detect short to B+ in the air bag assembly circuits.

DTC Will Set When:

“Ignition 1" is within the normal operating v oltage range.

Once these conditions are met and the voltage at

“Passenger Bag Low" is above a specified value,

Diagnostic Trouble Code (DTC) 19 will set. This test is

run once each ignition cycle and “Continuous

Monitoring".

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

DTC 19 and also DTC 71.

DTC Will Clear When:

The SDM is replaced.

DTC Chart Test Desc ription:

Number(s) below refer to step number(s) on the

diagno sti c ch art:

2. This test determines whether the malfunction is in the

SDM.

3. This test isolates the malfunction to one side of the

passenger air bag assembly y ellow 2–pin connector

behind glove box compartment.

4. This test determines whether the malfunction is in

Circuit(CKT) IB07–YELLOW/GREEN.

5. This test determines whether the malfunction is in

CKT IB08–YEL LOW/RED.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

to B+ in the passenger air bag assembly circuit.

Inspect CKTs IB07–YELLOW/GREEN and IB08–

YELLOW/RED carefully for cutting or chafing. If the

wiring pigtail of the passenger air bag assembly is

damaged, the component must be replaced. A careful

inspection of CKT IB07–YELLOW/GREEN and IB08–

YELLOW/RED, including the passenger air bag

assembly pigtail is essential to ensure that the

replacement Sensing and Diagnostic Module (SDM) will

not be damaged.

DTC 19 Passenger Deployment Loop Short To Voltage

CAUTION: When DTC 19 has been set, it is

necessary to replace the Sensing and Diagnostic

Module (SDM). Setting Diagnostic Troub le Code

(DTC) 19 and 25 or 51 or 53 will also cause DTC 71

to set. When a scan tool “CLEAR CODES"

command is issued and the malfunction is no

longer present, DTC 71 will remain current. Ensure

that the short to voltage condition is repaired prior

to installing a replacement SDM to avoid damaging

the SDM.

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Connect scan tool data link connector. Follow directions as

given in the scan tool operator's manual.

4. Ignition switch “ON."

5. Read passenger sense LO.

Is passenger sense LO more than 3.5 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Disconnect passenger air bag assembly yellow 2–pin

connector behind the glove box assembly.

3. Leave driver air bag assembly connected.

4. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to passenger air bag assembly

harness connector.

5. Ignition switch “ON."

Is passenger sense LO more than 3.5 volts? Go to Step 4

Ignition switch

“OFF."

Replace

passenger air

bag assembly.

Go to Step 6

4 1. Ignition switch “OFF."

2. Disconnect SDM.

3. Disconnect SRS driver / passenger load tool.

4. Measure resistance on SDM harness connector from

terminal “15" to terminal “12" (IGNITION 1).

Does DVM display “0L" (infinite)? Go to Step 5

Replace SRS

harness.

Go to Step 6

5 Measure resistance on SDM harness connector from terminal

“16" to terminal “12" (IGNITION 1).

Does DVM display “0L" (infinite) ? Go to Chart A.

Replace SRS

harness.

Go to Step 6

6 1. Reconnect all components, ensure all component are

properly mounted.

2. Ignition switch “ON."

Is passenger sense LO less than 3.5 volts?

Ignition switch

“OFF."

Replace SDM .

Go to Step 7 Go to Chart A.

7 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 7

DTC 21 Driver Deployment Loop Resistance High

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

The SDM then proceeds with the “Resistance

Measurement Test" “Driver Bag Low" terminal “4" is

grounded through a current sink and the driver current

source connected to “Driver Bag High" terminal “3"

allows a known amount of current to flow . By monitoring

the voltage difference between “Driver Bag High" and

“Driver Bag Low", the SDM calculates the combined

resistance of the driver air bag assembly, SRS coil

assembly, harness wiring Circuits(CKTs) IB05–

YELLOW and IB06–YELLOW/BLACK, and connector

terminal contact.

DTC Will Set When:

The combined resistance of the driver air bag assembly,

SRS Coil assembly, harness wiring CKTs IB05–

YELLOW and IB06–YELLOW/BLACK, and connector

terminal contact is above a specified value. This test

run once each ignition cycle during the “Resistance

Measurement Test" when:

No “higher priority faults" are detected during “Turn–ON"

“Ignition 1" voltage is in the specified value.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

DTC 21.

DTC Will Clear When:

The ignition switch is turned “OFF".

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

3. This test verifies proper connection of the yellow 2–

pin connector at the base of the steering column.

4. This test checks for proper contact and/or corrosion

of the 2–pin connector terminals at the base of

steer i ng column.

5. This test isolate the malfunction to one side of the

Supplemental Restraint System (SRS) coil assembly

yellow 2– pin connector located at the base of the

steer i ng column.

6. This test determines whether the malfunction is due

to high resistance in the wiring.

7. This test determines whether the malfunction is in the

SRS coil assembly or the driver air bag assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a poor

connection at terminals “1" and “2" of the SRS coil 2–

pin connector at the base of the steering column,

terminal “1" and “2" of the driver air bag assembly 2–pin

connector at the top of the steering column, SDM

terminals “3" and “4" or a poor wire to terminal

connection in Circuit IB05–YELLOW or IB06–YELLOW/

BLA CK. The test for this diagnostic trouble code is only

run while the “AIR BA G" warning lamp is performing the

bulb check, unless Diagnostic Trouble Code (DTC) 17 or

DTC 26 is detected. When a scan tool “Clear Codes"

command is issued and the malfunction is still present,

the DTC will not reappear until the next ignition cycle.

DTC 21 Driver Deployment Loop Resistance High

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Use scan tool data list function, read and record the driver

deployment loop resis tan ce.

Is driver deployment loop resistance more than 4.4 ohms? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Disconnect driver air bag assembly yellow 2–pin connector

located at base of steering column is seated properly.

Is the 2–pin connector connected properly? Go to Step 4

Seat SRS coil

assembly 2–pin

connector

properly.

Go to Step 8

4 1. Disconnect and inspect the SRS coil assemb ly yellow 2–pin

connector located base of steering column.

2. If OK, reconnect the SRS coil assembly yellow 2–pin

connector.

3. Ignition switch “ON."

Is DTC 21 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 8

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag assembly yellow

2–pin connectors located at the base of steering column and

behind the glove box assembly.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 21 current? Go to Step 6 Go to Step 7

6 1. Ignition switch “OFF."

2. There has been a increase in the total circuit resistance of the

driver deplo yment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB05–YEL/IB06–YEL/BLK, and SDM

connector terminal “3" and “4" to locate the root cause.

Was a fault found?

Replace SRS

harness.

Go to Step 8 Go to Chart A.

7 1. Ignition switch “OFF."

Disconnect SRS driver / passenger load tool from SRS coil

assembly harness connector.

Connect SRS driver / passenger load tool 5–8840–2421–0

on the top of steering column.

Reconnect SRS coil assembly harness connector as the

base of steering column.

Ignition switch “ON."

Is DTC 21 current?

Ignition switch

“OFF."

Replace SRS

COIL

ASSEMBLY.

Refe r to in this

section.

Go to Step 8

Ignition switch

“OFF."

Replace driver

air bag

assembly.

Go to Step 8

8 Reconnect all components, ensure all component are properly

mounted.

Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 8.

DTC 22 Driver Deployment Loop Resistance Low

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges. The SDM then

proceeds with the “Resistance Measurement Test"

“Driver Bag Low" terminal “4" is grounded through a

current sink and the driv er current source connected to

“Driver Bag High" terminal “3" allows a known amount

of current to flow. By monitoring the voltage diff erence

between “Driver Bag High" and “Driver Bag Low" the

SDM calculates the combined resistance of the driver

air bag assembly, Supplemental Restraint System

(SRS) coil assembly, harness wiring Circuits(CKTs)

IB05–YELLOW and IB06–YELLOW/BLACK and

connector terminal contact.

DTC Will Set When:

The combined resistance of the driver air bag assembly,

SRS coil assembly, harness wiring CKTs IB05–

YELLOW and IB06–YELLOW/BLACK and connector

terminal contact is abov e a specified v alue. This test is

run once each ignition cycle during the “Resistance

Measurement Test" when:

1. No “higher priority faults" are detected during “Turn–

ON"

2. “Ignition 1" voltage is in the specified value.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

DTC 22.

DTC Will Clear When:

The ignition switch is turned “OFF."

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

3. This test verifies proper connection of the yellow 2–

pin connector at the base of the steering column.

4. This test checks for proper operation of the shorting

clip in the yellow 2–pin connector.

5. This test isolate the malfunction to one side of the

Supplemental Restraint System (SRS) coil assembly

yellow 2–pin connector located at the base of

steer i ng column.

6. This test determines whether the malfunction is due

to shorting in the wiring.

7. This test determines whether the malfunction is in the

SRS coil assembly or the driver air bag assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

between Circuits IB05–YELLOW or IB06–YELLOW/

BLACK or a malfunctioning shorting clip on the driver air

bag assembly or SRS coil assembly which would

require replacement of the component. The test for this

diagnostic trouble code is only run while the “AIR BAG"

warning lamp is performing the bulb check, unless

Diagnosti c Tr ouble Code (DTC) 17 or DTC 26 is

detected. When a scan tool “Clear Codes" command is

issued and the malfunction is still present, the DTC will

not reappear until the next ignition cycle.

DTC 22 Driver Deployment Loop Resistance Low

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Use scan tool data list function, read and record the driver

deployment loop resis tan ce.

Is driver resist. less than 1.9 ohms? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Make sure the SRS coil assembly yellow 2–pin connector

located at the base of steering column is seated properly.

Is the 2–pin connector connected properly? Go to Step 4

Seat driver air

bag assembly

2–pin connector

properly.

Go to Step 8

4 1. Disconnect and inspect the SRS coil assemb ly yellow 2–pin

connector located base of steering column.

2. If OK, reconnect the driver air bag assembly yellow 2–pin

connector.

3. Ignition switch “ON."

Is DTC 22 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 8

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag 2–pin connectors

located at the base of steering column and behind the glove

box assembly.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 22 current? Go to Step 6 Go to Step 7

6 1. Ignition switch “OFF."

2. There has been a decrease in the total circuit resistance of

the driver deployment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB05–YEL and IB06–YEL/BLK, and SDM

connector terminal “3" and “4" to locate the root cause.

Was a fault found?

Replace SRS

harness.

Go to Step 8 Go to Chart A.

7 1. Ignition switch “OFF."

2. Disconnect SRS driver / passenger load tool from SRS coil

assembly harness connector.

3. Connect SRS driver / passenger load tool 5–8840–2421–0 to

the top of steering column.

4. Reconnect SRS coil assembly harness connector as the

base of steering column.

5. Ignition switch “ON."

Is DTC 22 current?

Ignition switch

“OFF."

Replace SRS

coil assembly.

Refe r to in this

section.

Go to Step 8

Ignition switch

“OFF."

Replace driver

air bag

assembly.

Go to Step 8

8 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 8

DTC 24 Driver Deployment Loop Short To Ground

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

The SDM monitors the voltage at “Driver Bag Low"

terminal “4" and “Passenger Bag Low" terminal “16" to

detect shorts to ground in the air bag assembly circuits.

DTC Will Set When:

Neither of the two air bag assemblies is open.

“Ignition 1" is within the normal operating v oltage range.

This test is run once each ignition cycle and

“Continuous Monitoring". Once these conditions are

met and the voltage at “Driver Bag Low" is below a

specified value, DTC 24 will set.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

The malfunction is no longer occurring and the ignition

is turned “OFF."

DTC Chart Test Desc ription:

Number(s) below refer to step number(s) on the

diagno sti c ch art:

2. This test determines whether the SDM is

malfunctioning

3. This test isolates the malfunction to one side of the

Supplemental Restraint System (SRS) coil assembly

yellow 2–pin connector at the base of the steering

column.

4. This test determines whether the malfunction is in

Circuit(CKT) IB05–YELLOW.

5. This test determines whether the malfunction is in

CKT IB06–Y EL LOW/BLACK.

6. This test determines whether the malfunction is in the

SRS coil assembly or the driver air bag assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

to ground in the driver air bag assembly circuit. Inspect

CKTs IB05–YELLOW and IB06–YELLOW/BLACK

carefully f or cutting or chafing.

DTC 24 Driver Deployment Loop Shor t To Ground

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Connect scan tool data link connector. Follow directions as

given in the scan tool operator's manual.

Ignition switch “ON."

4. Read driver sens e LO.

Is driver sense LO less than 1.5 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Disconnect SRS coil assembly yellow 2–pin connector

located at base of the steering column. Leave passenger air

bag assembly connected.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil assembly harness

connector.

4. Ignition switch “ON."

Is DTC 24 current? Go to Step 4 Go to Step 6

4 1. Ignition switch “OFF."

2. Disconnect SDM.

3. Disconnect SRS driver / passenger load tool.

4. Measure resistance on SDM harness connector “3" to

terminal “6" (ground).

Does DVM display “0L" (infinite)? Go to Step 5

Replace SRS

harness.

Go to Step 7

5 Measure resistance on SDM harness connector from terminal “4"

to terminal “6" (ground).

Does DVM display “0L" (infinite) ? Go to Chart A.

Replace SRS

harness.

Go to Step 7

6 1. Ignition switch “OFF."

2. Disconnect SRS driver / passenger load tool 5–8840–2421–0

from SRS coil assembly harness connector.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter 5–8840–0385–0 to driver air bag

assembly harness connector. Located top of the steering

column.

4. Reconnect SRS coil assembly harness connector as the

base of steering column.

5. Ignition switch “ON."

Is DTC 24 current?

Ignition switch

“OFF."

Replace SRS

coil assembly.

Refe r to in this

section.

Go to Step 7

Ignition switch

“OFF."

Replace driver

air bag

assembly.

Go to Step 7

7 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 7

DTC 25 Driver Deployment Loop Short To Voltage

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

The SDM monitors the voltage at “Driver Bag Low"

terminal “4" and “Passenger Bag Low" terminal “16" to

detect shorts to B+ in the air bag assembly circuits.

DTC Will Set When:

“Ignition 1" is in the normal operating voltage range.

This test is run once each ignition cycle and

“Continuous Monitoring". Once these conditions are

met and the voltage at “Driver Bag Low" is above a

specified value, Diagnostic Trouble Code (DTC) 25 will

set.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

DTC 25 and also DTC 71

DTC Will Clear When:

The SDM is replaced.

DTC Chart Test Desc ription:

Number(s) below refer to step number(s) on the

diagno sti c ch art:

2. This test determines whether the SDM is

malfunctioning.

3. This test isolates the malfunction to one side of the

Supplemental Restraint System coil assembly yellow

2–pin connector at the base of steering column.

4. This test determines whether the malfunction is in

Circuit(CKT) IB05–YELLOW.

5. This test determines whether the malfunction is in

CKT IB06–Y EL LOW/BLACK.

6. This test determines whether the malfunction is in the

Supplemental Restraint System (SRS) coil assembly

or the driver air bag assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short

to B+ in the driver air bag assembly circuit. Inspect

CKTs IB05–YELLOW and IB06–YELLOW/BLACK

carefully for cutting or chafing. If the wiring pigtail of the

driver air bag assembly and SRS coil assembly is

damaged, the components must be replaced. A

careful inspection of CKT IB05–YELLOW and IB06–

YELLOW/BLACK, including the SRS coil assembly and

driver air bag assembly is essential to ensure that the

replacement Sensing and Diagnostic Module (SDM) will

not be damaged.

DTC 25 Driver Deployment Loop Short To Ignition

CAUTION: When Diagnostic Trouble Code (DTC) 25

has been set, it is necessary to replace the Sensing

and Diagnostic Module (SDM). Setting DTC 25 will

also cause DTC 71 to set. When a scan tool “CLEAR

CODES" command is issued and the malfunction is

no longer present, DTC 71 will remain current.

Ensure that the short to voltage condition is

repaired prior to installing a replacement SDM to

avoid damaging the SDM.

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Ignition switch “OFF."

3. Connect scan tool data link connector. Follow directions as

given in the scan tool operator's manual.

4. Ignition switch “ON."

5. Read driver sens e LO.

Is driver sense LO more than 3.5 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Disconnect SRS coil assembly yellow 2–pin connector at the

base of the steering column. Leave passenger air bag

assembly connected.

Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil assembly harness

connector.

3. Ignition switch “ON."

Is driver sense LO more than 3.5 volts? Go to Step 4 Go to Step 6

4 1. Ignition switch “OFF."

2. Disconnect SDM.

3. Disconnect SRS drive / passenger load tool.

4. Measure resistance on SDM harness connector from

terminal “3" to terminal “12" (Ignition 1).

Does DVM display “0L" (infinite)? Go to Step 5

Replace SRS

harness.

Go to Step 7

5 Measure resistance on SDM harness connector from terminal “4"

to terminal “12" (Ignition 1).

Does DVM display “0L" (infinite) ? Go to Chart A.

Replace SRS

harness.

Go to Step 7

6 1. Ignition switch “OFF."

2. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter 5–8840–0385–0 to driver air bag

assembly harness connector located of top of the steering

column.

3. Reconnect SRS coil assembly harness connector as the

base of steering column.

4. Ignition switch “ON."

Is driver sense LO more than 3.5 volts?

Ignition switch

“OFF."

Replace SRS

coil assembly.

Go to Step 7

Ignition switch

“OFF."

Replace driver

air bag

assembly.

Go to Step 7

7 1. Reconnect all components, ensure all components are

properly mounted.

2. Ignition switch “ON."

Is passenger sense LO less than 3.5 volts? Replace SDM .

Go to Step 8 Go to Chart A.

8 1. Reconnect all components, ensure all components are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 8

Step Action Yes No

DTC 26 Driver Deployment Loop Open

D09RX002

Circuit Description:

When the ignition switch is turned “ON", the Sensing

and Diagnostic Module (SDM) will perform tests to

diagnose critical malfunctions within itself. Upon

passing these tests, “ignition 1", and deployment loop

voltages are measured to ensure they are within their

respective normal voltage ranges.

During “Continuous Monitoring" diagnostics, a fixed

amount of current is following in the deployment loop.

This produces proportional voltage drops in the loop.

By monitoring the voltage difference between “Driver

Bag High" and “Driver Bag Low", the SDM calculates

the combined resistance of the driver air bag assembly,

SRS coil assembly, harness wiring Circuits(CKTs)

IB05–YELLOW and IB06–YELLOW/BLACK, and

connector terminal contact.

DTC Will Set When:

The voltage difference between “Driver Bag High"

terminal “3" and “Driver Bag Low" terminal “4" is above

or equal to a specified value f or 500 milliseconds during

“Continuous Monitoring."

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

The voltage difference between “Driver Bag High"

terminal “3" and “Driver Bag Low" terminal “4" is below

a specified value for 500 milliseconds during

“Continuous Monitoring."

DTC Chart Test Description:

Number(s) below refer to circled number(s) on the

diagnostic chart:

1. This test determines whether the malfunction is in the

Sensing and Diagnostic Module (SDM).

2. This test verifies proper connection of the yellow 2–

pin connector at the base of the steering column.

3. This test checks for proper contact and/or corrosion

of the yellow 2–pin connector at the base of the

steer i ng column.

4. This test isolates the malfunction to one side of the

Supplemental Restraint System (SRS) coil assembly

yellow 2–pin connector located at the base of

steer i ng column.

5. This test determines whether the open is in the

wiring.

6. This test determines whether the malfunction is in the

SRS coil assembly or the driver air bag assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a poor

connection at the driver air bag assembly harness 2–

pin connector terminals “1" and “2" at the top of the

steering column, SRS coil assembly harness 2–pin

connection terminals “1" and “2", SDM terminals “3"

and “4", or an open in Circuits(CKTs) IB05–YELLOW

and IB06–YELLOW/BLACK.

DTC 26 Driver Deployment Loop Open

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. When measurements are requested in this chart use 5–

8840–0285–0 DVM with correct terminal adapter from 5–

8840–0385–0.

2. Use scan tool data list function, read and record the driver

diff erential voltage.

Is driver differential voltage more than 4.25 volts? Go to Step 3 Go to Chart A.

3 1. Ignition switch “OFF."

2. Make sure the SRS coil assembly yellow 2–pin connector

located at the base of steering column is seated properly.

Is the yellow 2–pin connector connected properly? Go to Step 4

Seat driver air

bag assembly

2–pin

connector.

Go to Step 8

4 1. Disconnect and inspect the SRS coil assemb ly yellow 2–pin

connector located base of steering column.

2. If OK, reconnect the SRS coil assembly yellow 2–pin

connector.

3. Ignition switch “ON".

Is DTC 26 current? Go to Step 5

Ignition switch

“OFF."

Go to Step 8

5 1. Ignition switch “OFF."

2. Disconnect SRS coil and passenger air bag assembly, yellow

2–pin connectors located at the base of steering column and

behind the glove box assembly.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil and passenger air bag

assembly harness connectors.

4. Ignition switch “ON."

Is DTC 26 current? Go to Step 6 Go to Step 7

6 1. Ignition switch “OFF."

2. There has been an open circuit in the driver deployment loop.

Use the high resolution ohmmeter mode of the DVM while

checking CKTs IB05 YEL and IB06 YEL/BLK, and SDM

connector terminal “3" AND “4" to locate the root cause.

Was a fault found?

Replace SRS

harness.

Go to Step 8 Go to Chart A.

7 1. Ignition switch “OFF."

2. Disconnect SRS driver / passenger load tool from SRS coil

assembly harness connector.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

on steer i ng colum n.

4. Reconnect SRS coil assembly harness connector as the

base of steering column.

5. Ignition switch “ON."

Is DTC 26 current?

Ignition switch

“OFF."

Replace SRS

coil assembly,

refer to in this

section.

Go to Step 8

Ignition switch

“OFF."

Replace driver

air bag

assembly.

Go to Step 8

8 1. Reconnect all components, ensure all component are

properly mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic System

Check." Go to Step 8

DTC 51 Deployment Event Commanded

D09RX002

Circuit Description:

The Sensing and Diagnostic Module (SDM) contains a

sensing device which conv erts vehicle velocity changes

to an electrical signal. The electrical signal generated

is processed by the SDM and then compared to a value

stored in memory. When the generated signal exceeds

the stored value, the SDM will cause current to flow

through the air bag assembly deploying the air bags and

causing Diagnostic Trouble Code (DTC) 51 to set.

DTC Will Set When:

The SDM detects a frontal crash, up to 30 degrees off

the centerline of the vehicle, of sufficient force to

warrant deployment of the air bags.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp records

“Crash Data", and sets a diagnostic trouble code.

DTC Will Clear When:

The SDM is replaced.

DTC Chart Test Desc ription:

Number(s) below refer to step number(s) on the

diagno sti c ch art:

2. If air bag assembly (s) has not deplo yed, DTC 51 may

have falsely set.

3. If DTC 51 has set with no signs of frontal impact, the

diagnostic trouble code has falsely set.

DTC 51 Deployment Event Commanded

WARNING: DURING SERVICE PROCEDURES. BE

VER Y CAREFUL WHEN HANDLING A SENSING AND

DIAGNOSTIC MODULE (SDM). NEVER STRIKE OR

J AR THE SDM. NEV ER PO WER UP THE S RS WHEN

THE SDM IS NOT RIGIDLY ATTACHED TO THE

VEHICLE. ALL SDM AND MOUNTING BRACKET

FASTENERS MUST BE CAREFULLY TORQUED

AND THE ARROW MUST BE POINTING TOWARD

THE FRONT OF THE VEHICLE TO ENSURE PROPER

OPERATION OF THE SUPPLEMENTAL RESTRAINT

SYSTEM (SRS). THE SDM COULD BE ACTIVATED

WHEN POWERED WHIL E NOT RIGIDLY ATTACHED

TO THE VEHICLE WHICH COULD CAUSE

DEPLOYMENT AND RESULT IN PERSONAL INJURY.

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 Ignition switch “OFF."

Have air bag assemblies deployed? Replace

components

and perform

inspections as

directed in

“repa irs and

inspections

required after

an accident" in

this section.

Clear

diagnostic

trouble codes.

Repeat the

“SRS

Diagnostic

System Check." Go to Step 3

3 Inspect front of vehicle and undercarriage for signs of impact.

Were signs of impact found? Replace

components

and perform

inspections as

directed in

“repa irs and

inspections

required after

an accident" in

this section.

Clear

diagnostic

trouble codes.

Repeat the

“SRS

Diagnostic

System Check."

Ignition switch

“OFF."

Replace SDM.

Reconnect all

SRS system

components,

ensure all

components

are properly

mounted.

Repeat the

“SRS

Diagnostic

System Check."

DTC 53 Deployment Commanded With Deployment Loop Fault Or Energy

Reserves Out Of Range

D09RX002

Circuit Description:

The Sensing and Diagnostic Module (SDM) contains a

sensing drive which converts vehicle velocity changes

to an electrical signal. The electrical signal generated

is processed by the SDM and then compared to a value

stored in memory. When the generated signal exceeds

the stored value, the SDM will cause current to flow

through the air bag assembly deploying the air bags.

Diagnostic Trouble Code (DTC) 53 is set accompanying

with DTC 51 when a deploy ment occurs while an air bag

assembly circuit fault is present that could possible

result in a no deployment situation in one or both air bag

assemblies.

DTC Will Set When:

The SDM detects a frontal crash, up to 30 degrees off

the centerline of the vehicle, of sufficient force to

warrant deployment of the air bags and an inflator circuit

fault is present.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp records

“Crash Data", and sets a diagnostic trouble code.

DTC Will Clear When:

The SDM is replaced. If DTC 53 is set, one or more

DTCs will be set in addition to DTC 53. Malfunction(s)

setting DTC(s) (other than DTC 71) must be repaired so

that DTC(s) will not be set when a new SDM is

installed.

DTC Chart Test Description:

Number(s) below refer to step number(s) on the

diagnostic chart:

2. If air bag assembly has not deployed, Diagnostic

Trouble Code (DTC) 53 may have falsely set.

3. If DTC 53 has set with no signs of frontal impact, the

diagnostic trouble code has falsely set.

DTC 53 Deployment Commanded With Deployment Loop Fault Or Energy Reserves Out Of

Range

WARNING: DURING SERVICE PROCEDURES. BE

VER Y CAREFUL WHEN HANDLING A SENSING AND

DIAGNOSTIC MODULE (SDM). NEVER STRIKE OR

J AR TH E SDM. NEVER POWER UP THE SRS WHEN

THE SDM IS NOT RIGIDLY ATTACHED TO THE

VEHICLE. ALL SDM AND MOUNTING BRACKET

FASTENERS MUST BE CAREFULLY T ORQUED AND

THE ARROW MUST BE POINTING TOWARD THE

FRONT OF THE VEHICLE TO ENSURE PROPER

OPERATION OF THE SRS. THE SDM COULD BE

A CTIVATED WHEN PO WERED WHILE NOT RIGIDLY

ATTACHED T O THE VEHICLE WHICH COULD

CAUSE DEPLOYMENT AND RESULT IN PERSONAL

INJURY.

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 Ignition switch “OFF."

Have air bag assemblies deployed? Replace

components

and perform

inspections as

directed in

“repa irs and

inspections

required after

an accident" in

this section.

Clear

diagnostic

trouble codes.

Repeat the

“SRS

Diagnostic

System Check." Go to Step 3

3 Inspect front of vehicle and undercarriage for signs of impact.

Were signs of impact found? Replace

components

and perform

inspections as

directed in

“repa irs and

inspections

required after

an accident" in

this section.

Clear

diagnostic

trouble codes.

Repeat the

“SRS

Diagnostic

System Check."

Ignition switch

“OFF."

Replace SDM.

Reconnect all

SRS system

components,

ensure all

components

are properly

mounted.

Repeat the

“SRS

Diagnostic

System Check."

DTC 61 Warning Lamp Circuit Failure

D09RX002

Circuit Description:

When the ignition switch is turned “ON", battery voltage

is applied to the “AIR BAG" warning lamp and to the

“ignition 1" input terminal “12". The Sensing and

Diagnostic Module (SDM) responds by flashing the “AIR

BAG" warning lamp seven times. The SDM monitors

the lamp driver output by comparing the output state at

“Supplemental Restraint System (SRS) warning lamp"

terminal “7" to the microprocessor commanded state.

When “ignition 1" is in the specified value, and the

output state Does not match the commanded state of

the lamp driver for 500 milliseconds, DTC 61 is set.

DTC Will Set When:

“Ignition 1" voltage is in the specified value and the

output state at the “SRS warning lamp" terminal does

not match the commanded state of the lamp driver for

500 milliseconds. This test is run every 100

milliseconds during “Continuous Monitoring" tests and

once per each ignition cycle at the beginning.

Action Taken:

SDM attempts to turn “ON" the “AIR BAG" warning lamp

and sets a diagnostic trouble code.

DTC Will Clear When:

The ignition switch is turned “OFF."

Diagnostic Aids:

Refer to Charts B and C to diagnose warning lamp

circuit malfunctions.

DTC 61 Warning Lamp Circuit Failure

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 1. Malfunctions within the “AIR BAG" warning lamp circuitry will

set this diagnostic trouble code.

2. These malfunctions are addressed in the “SRS Diagnostic

System Check" via Chart B and Chart C.

3. Failure to properly perf orm the “SRS Diagnostic System

Check" may result in misdiagnosis.

4. Ignition switch “ON."

5. Clear SRS diagnostic trouble codes.

Is DTC 61 SET?

Ignition switch

“OFF."

Go to Chart A.

Repeat the “SRS

Diagnostic System

Check."

DTC 71 Internal SDM Fault

D09RX002

Circuit Description:

Diagnostic Trouble Code (DTC) 71 is an indication of a

potential internal Sensing and Diagnostic Module

(SD M) malfunction and will set if any of the following

conditions are detected:

1) Deployment or microprocessor energy reserve

failure.

2) Electronically Erasable Programmable Read Only

Memory failure. (EEPROM).

3) Random Only Memory failure. (ROM).

4) Random Access Memory failure. (RAM).

5) Calibration check sum failure.

6) Deployment switch faults.

7) Accelerometer fault.

8) Arming sensor fault.

9) Diagnostic current faults.

10) DTC 19

11) DTC 25

12) DTC 51

13) DTC 53

DTC Will Set When:

Any of the above indicated malfunctions are detected by

the SDM. The malfunctions described above are

tested mainly during “Continuous Monitoring" and some

ones run each ignition cycle.

Action Taken:

SDM turns “ON" the “AIR BAG" warning lamp and sets

a diagnostic trouble code.

DTC Will Clear When:

A scan tool “Clear Codes" commanded is received by

the SDM. Some of the indicated malfunctions will only

allow the “AIR BA G" warning lamp to go out.

But when DTC 19, 25, 51, 53 are also set, SDM is

Replaced.

DTC 71 Internal SDM Fault

WARNING: DURING SERVICE PROCEDURES. BE

VERY CAREFUL WHEN HANDLING A SENSING AND

DIAGNOSTIC MODULE (SDM). NEVER STRIKE OR

JAR THE SDM. NEVER POWER UP THE SRS WHEN

THE SDM IS NOT RIGIDLY ATTACHED TO THE

VEHICLE. ALL SDM AND MOUNTING BRACKET

FASTENERS MUST BE CAREFULLY TORQUED

AND THE ARROW MUST BE POINTING TOWARD

THE FRONT OF THE VEHICLE TO ENSURE PROPER

OPERATION OF THE SRS. THE SDM COULD BE

ACTIVATED WHEN POWERED WHILE NOT RIGIDLY

ATTACHED TO THE VEHICLE WHICH COULD

CAUSE DEPLOYMENT AND RESULT IN PERSONAL

INJURY.

CAUTION: When Diagnostic Trouble Code (DTC) 19

or 25 or 51 or 53 has been set it is necessary to

Replace the SDM. Setting DTC 19 and 25 or 51 or 53

will also cause DTC 71 to set. When a scan tool

“CLEAR CODES" command is issued and the

malfunction is no longer present, DTC 51 or 53 and

DTC 71 will remain current. Ensure that the short to

v oltage condition DTC 19, 25 is repaired prior to

installing a Replacement SDM to avoid damaging

the SDM.

Step Action Yes No

1 Was the “SRS Diagnostic System Check" performed?

Go to Step 2

Go to the “SRS

Diagnostic System

Check."

2 Note SRS “Diagnostic System Check."

Is DTC 19 or 25 or 51 or 53 also set (current or history)? (Refer to

notice above).

Go to DTC 19 if

DTC 19 is set.

Go to DTC 25 if

DTC 25 is set.

Go to DTC 51 if

DTC 51 is set.

Go to DTC 53 if

DTC 53 is set.

Ignition switch

“OFF."

Replace SDM.

Repeat the

“SRS

Diagnostic

System Check."