GM Service Manual Online
For 1990-2009 cars only
Battery Voltage Signal: The scan tool displays the system voltage of the vehicle.

Chime: The scan tool displays On or Off. The state of the chime as commanded by the instrument panel cluster (IPC).

Cruise Control Active: The scan tool displays Yes or No. The status of the cruise control switch as commanded by the PCM.

DIC Switch: The scan tool displays Clear, Info, Menu or Reset. The status of the driver information center (DIC) buttons as commanded by the DIC.

Driver Door Ajar Switch: The scan tool displays Door Closed or Door Ajar. The status of the drivers door switch as commanded by the body control module (BCM).

ECT Sensor: The scan tool displays -40 to +151°C (-40 to +304°F). The powertrain control module (PCM) monitors the voltage at the signal circuit of the engine coolant temperature sensor. The voltage is inversely proportional to the engine coolant temperature.

Engine Oil Life Remaining: The scan tool displays 0-100%. The PCM calculates the amount of engine oil life remaining.

Engine Oil Pressure Switch: The scan tool displays OK or Low. The status of the engine oil pressure switch as commanded by the PCM. The PCM monitors the signal circuit of the EOP switch.

Engine Speed: The scan tool displays 0-9999 RPM. Engine speed is computed by the PCM. It should remain close to desired idle under various engine loads with the engine idling.

Fuel Level Sensor: The scan tool displays 0-5 volts. The PCM monitors the signal circuit of the fuel level sensor.

Fuel Tank Level Remaining: The scan tool displays 0-100%. The PCM calculates the amount of fuel remaining based on the signal circuit voltage of the fuel level sensor.

Generator Lamp Command: The scan tool displays On or Off. The status of the charge indicator as commanded by the PCM.

Ignition 1 Signal: The scan tool displays the system voltage of the vehicle.

Ignition Status: The scan tool displays On or Off. The state of the ignition as commanded by the BCM.

Key In Ignition Cylinder Switch: The scan tool displays Yes or No. The BCM monitors the signal circuit of the ignition switch.

MIL Circuit History: The scan tool displays OK, High or Low. The status of the MIL circuit as commanded by the PCM.

MIL Command: The scan tool displays On or Off. The status of the MIL indicator as commanded by the PCM.

Park Lamp Switch: The scan tool displays On or Off. The status of the park lamp switch as commanded by the BCM.

Vehicle Speed Sensor: The scan tool displays 0-255 km/h (0-155 mph). The PCM monitors the signal circuit of the vehicle speed sensor.