GM Service Manual Online
For 1990-2009 cars only
ABS Lamp: The scan tool displays Off or On. The status of the discrete back-up ABS indicator signal. The instrument cluster uses this input to determine illumination of the ABS indicator when the instrument cluster loses communication with the electronic brake control module (EBCM).

Calibration ID: The scan tool displays the calibration ID for the control module.

Catalyst Converter TT.: The scan tool displays On or Off. The status of the catalytic convertor temperature switch

Controlled Power: The scan tool displays 0-25.5 Volts. The system voltage detected by the IPC.

Daily Serial Number: The scan tool displays the daily serial number.

Dis. English/Metric Switch: The scan tool displays On or Off. The status of the discrete English/metric switch signal.

Dis. Information Reset Switch: The scan tool displays On or Off. The status of the discrete information reset switch signal. The instrument cluster uses this input to determine when to reset the currently displayed parameter.

Display Information Sw.: The scan tool displays On or Off. The status of the discrete information switch signal. The instrument cluster uses this input to determine when to toggle the DIC display.

Display Timer Switch: The scan tool displays On or Off. The status of the discrete timer switch signal.

Display Trip Reset Sw.: The scan tool displays On or Off. The status of the discrete trip reset switch signal. The instrument cluster uses this input to determine when to reset the trip odometer currently displayed.

Engine Speed: The scan tool displays from 0 to 7000 RPM. The current engine speed reported to the instrument cluster by the powertrain control module (PCM) via the discrete tachometer signal. The value should match the tachometer display.

Fast Idle Input: The scan tool displays On or Off. The status of the fast idle request.

Front Fog Lamp Switch: The scan tool displays On or Off. The input of the front fog lamps switch, a closed switch is displayed as On.

Fuel Door Release Switch: The scan tool displays On or Off.

Fuel Level: The scan tool displays 0 to 70 L (0 to 18.5 gal). The PCM monitors the fuel level sensor in order to determine the fuel level.

Head Lamp Switch: The scan tool displays On or Off. The status of the headlamp switch.

Highbeam Switch: The scan tool displays On or Off. The instrument panel cluster (IPC) uses this input to determine when to request the high beam headlamps to be activated.

Ignition 1: The scan tool displays On or Off. The status of the discrete ignition positive voltage signal.

Ignition Counter: The scan tool displays 0-255 counts. The ignition switch cycles.

Ignition OFF Position: The scan tool displays On or Off. The status of the ignition switch.

Incandescent Dim Pot: The scan tool displays 0-255 counts. The interior dimmer switch input signal.

Interior Lamp Switch: The scan tool displays On or Off. The input of the interior lamps switch, a closed switch is displayed as On

Julian Date of Build: The scan tool displays year and day. The first digit indicates the last digit of the year that the control module was built. The remaining 3 digits indicate the day of the year that the control module was built.

Key In Ignition: The scan tool displays Yes or No. The IPC monitors the status of the discrete key-in-ignition switch signal of the ignition switch. When the ignition is in OFF or ACCY, the driver's door is open, and the key is in the ignition, a medium rate multiple pulse chime sounds.

Last 4 Digits of Part No.: The scan tool displays last 4 digits of the control module part number.

Low Brake Fluid Level: The scan tool displays 0 to 5 Volts. The voltage of the brake fluid level sensor signal.

Low Brake Fluid Level: The scan tool displays On or Off. The status of the brake fluid level sensor signal.

Low Coolant Level: The scan tool displays On or Off. The status of the discrete engine coolant level switch signal. The instrument cluster uses this input to determine display of the CHECK COOLANT LEVEL message on the DIC.

Lt. Turn Signal Indicator: The scan tool displays On or Off. The status of the discrete left turn signal. The instrument cluster uses this input to determine when to flash the left turn indicator.

Oil Pressure Lamp: The scan tool displays On or Off. The status of the low oil pressure indicator as commanded by the IPC.

Park Lamp Switch: The scan tool displays On or Off. The status of the discrete park brake switch signal. The instrument cluster uses this input to determine illumination of the BRAKE indicator.

PROM ID: The scan tool displays the PROM ID for the control module.

Rear Fog Lamp Switch: The scan tool displays On or Off. The input of the rear fog lamps switch (export), a closed switch is displayed as On.

Rt. Turn Signal Indicator: The scan tool displays On or Off. The status of the discrete right turn signal. The instrument cluster uses this input to determine when to flash the right turn indicator.

Steering Wheel Controls: The scan tool displays Active or Idle. The input of the steering wheel control switches, a closed steering wheel control switch is displayed as Active.

Steering Wheel Controls: The scan tool displays 0-255 counts. The steering wheel control switch input signal. Each steering wheel control switch has a different value.

Trunk Release Switch: The scan tool displays On or Off. The input of the trunk release switch, a closed switch is displayed as Off.

Twilight Delay: The scan tool displays 0-255  counts. The twilight delay control input signal.

Twilight Photo: The scan tool displays 0-255  counts. The ambient light sensor input signal.

Twilight Switch: The scan tool displays On or Off. The input of the twilight enable switch, a closed switch is displayed as Off.

Vehicle Speed Sensor: The scan tool displays mph or km/h. The vehicle speed as determined by the PCM.

Washer Fluid Level: The scan tool displays On or Off. The status of the discrete washer fluid level switch signal.

Wiper Activation Switch: The scan tool displays On or Off. The input of the wiper activation switch, a closed switch is displayed as Off.

Year Module Built: The scan tool displays the year that the control module was built.