
Powertrain Management – Diagnosis – GEN III V8 Engine Page 6C3-2-5
Page 6C3-2-5
Coolant Temperature: TECH 2 Displays a range of -39°C to 140°C
The Engine Coolant Temperature (ECT) Sensor is mounted in the cylinder head of the left bank. The PCM applies 5.0
volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes.
When the sensor is cold (internal resistance high), the PCM monitors a high signal voltage and interprets the voltage as
a cold engine. As the sensor warms (internal resistance decreases), the voltage signal decreases and the PCM
interprets the lower voltage as a warm engine.
Barometric Pressure: TECH 2 Displays a range of 0 to 200 kPa
The BARO reading is displayed in kPa and represents the altitude of the vehicle for the transmission control. At sea level
the BARO reading is about 101 kPa. At 3,048 meters the BARO reading is about 96 kPa.
Vehicle Speed: TECH 2 Displays a range of 0 to 255 km/h
The vehicle speed sensor signal is converted into km/h for display.
A/C Clutch: TECH 2 Displays "ON" or "OFF"
Represents the commanded state of the A/C clutch control relay. Clutch should be engaged when ON is displayed.
A/C Pressure: TECH 2 Displays a range of 0 to 3195 kPa
The kPa displayed indicates that the PCM is monitoring an A/C Refrigerant Pressure signal voltage which is too high or
too low to allow the A/C compressor clutch to engage.
Low Speed Fan Request: TECH 2 Displays "ON" or "OFF
Indicates if the engine cooling fan low speed relay has been commanded ON or OFF.
Low Fan Run On: TECH 2 Displays "NO" o r "YES"
This indicates if the PCM is requesting the BCM to turn the Low Speed Fan ON at key OFF.
Auto Learn Active: TECH 2 Displays "NO" or "YES"
This indicates if the PCM Auto Learn Mode is Active when TECH 2 displays YES.
Password Learning: TECH 2 Displays "NO" or "YES"
This indicates if the PCM is learning the PIM password.
Theft Status: TECH 2 Displa ys "NO STAR T" or "START"
Indicates the status of the Theft Deterrent System.
PCM DTC Status: TECH 2 Displ ays "NO DTC" or “DTC SET”
Indicates if a DTC is set. This does not indicate what DTC is set, just informs that DTC(s) are or are not set.
Malfunction Indicator Lamp (MIL): TECH 2 Displays "OFF" or "ON"
Indicated if the instrument panel Malfunction Indicator Lamp (MIL) is activated or not.
Throttle Failure: TECH 2 Displays "NO" or "YES"
Indicates if the throttle position sensor has failed. This is reported from the PCM to the PIM.
MAP Failure: TECH 2 Displays "NO" or "YES"
Indicates if the Map sensor has failed. This is reported from the PCM to the PIM.
MFD Message: TECH 2 Displays "NO" o r "YES"
Indicates if PCM is sending an additional MFD message to the instruments.
Fuel Used: TECH 2 Displays a range of 0 to 1000 Litres
When the key is turned ON and the engine is running, the PCM will calculate FUEL USED during each ignition cycle.
Fuel Flow Rate: TECH 2 Displays a range of 0 to 100 litres
Indicates fuel consumption per litres per hour.
Engine Type: TECH 2 Displays Engine Type
The TECH 2 uses this information for proper TECH 2 scan tool software.