GM Service Manual Online
For 1990-2009 cars only
ABS Telltale: The scan tool displays On or Off. The state of the antilock brake system (ABS) indicator as commanded by the instrument panel cluster (IPC).

Air Bag Telltale: The scan tool displays Activated or Not Activated. The state of the air bag indicator as commanded by the IPC.

Ambient Temperature Sensor: The scan tool displays 0-100°C. The measured temperature from the ambient outside air temperature sensor to the body control module (BCM).

Battery Lamp: The scan tool displays On or Off. The state of the battery indicator as commanded by the IPC.

Battery Voltage: The scan tool displays 0-19 volts. This is the voltage at the battery positive voltage circuit of the body control module (BCM).

Change Oil Telltale: The scan tool displays On or Off. The state of the change oil indicator as commanded by the IPC.

Coolant Temperature: The scan tool displays 38-128°C (100-260°F). The displayed coolant temperature gage value in the IPC. This value may slightly differ from the monitored coolant temperature.

Coolant Warning Lamp: The scan tool displays On or Off. The state of the coolant warning indicator as commanded by the IPC.

Cruise Control Active: The scan tool displays Yes or No. The state of the cruise control indicator as commanded by the powertrain control module (PCM).

Dimming Control Circuit: The scan tool displays Volts. The BCM monitors the voltage from the dimmer switch.

Door Ajar Lamp: The scan tool displays On or Off. The state of the door ajar indicator as commanded by the IPC.

Driver Door Ajar Switch: The scan tool displays Door Closed or Door Ajar. The state of the driver door ajar switch as commanded by the BCM.

ECT Sensor: The scan tool displays -40 to +151°C (-40 to +304°F). The 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 Left Remaining: The scan tool displays 0-100%. The PCM calculates the remaining engine oil life.

Engine Oil Pressure Switch: The scan tool displays OK or Low. The state of the engine oil pressure switch as commanded by the PCM.

Engine Speed: The scan tool displays 0-9999 RPM. The IPC monitors the engine speed signal circuit from the PCM via serial data.

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.

Ext. Trunk/Liftgate Rel Sw: The scan tool displays Active or Inactive. The state of the liftgate release switch as monitored by the BCM.

Fuel Gauge Position: The scan tool displays 0-100%. The IPC calculates the amount of fuel remaining in the tank based on the serial data messages from the PCM regarding fuel level.

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

Fuel Tank Level Remaining: The scan tool displays the state of the fuel level in percent. The PCM monitors the signal circuit of the fuel level sensor and displays the current fuel percentage.

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

Headlamp Switch: The scan tool displays Active or Inactive. The state of the headlamp switch as monitored by the BCM

High Beam Telltale: The scan tool displays On or Off. The state of the high beam indicator as commanded by the IPC.

Ignition 0 Signal: The scan tool displays On or Off. The ignition 0 signal represents the system voltage detected at the IPC.

Ignition 1 Signal: The scan tool displays 0-16 V. The ignition 1 signal represents the system voltage detected by the PCM at the ignition voltage circuit.

Incandescent Dimming PWM Cmd: The scan tool displays 0-100 percent. This is the dimming level of the backlight of the IPC as commanded by the BCM.

Key in Ignition Status: The scan tool displays Key In or Key Out. The state of the key in ignition switch as commanded by the BCM.

LCD Dimming: The scan tool displays 0-100 percent. This is the dimming level of the backlight of the IPC.

Left Rear Door Ajar Sw: The scan tool displays Door Closed or Door Ajar. The state of the left rear door ajar switch as commanded by the BCM.

MIL Circuit History: The scan tool displays OK, Open, Short, or Invalid State. This is the state of the MIL signal circuit as monitored by the PCM.

MIL (Malfunction Indicator Lamp) Command: The scan tool displays On or Off. This is the commanded state of the MIL (Malfunction Indicator Lamp) by the PCM.

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

Passenger Door Ajar Switch: The scan tool displays Door Closed or Door Ajar. The state of the passenger door ajar switch as monitored by the BCM.

Park Brake Switch: The scan tool displays Applied or Released. The state of the park brake switch as monitored by the BCM.

Parklamp Switch: The scan tool displays Active or Inactive. The state of the parklamp switch as monitored by the BCM.

Pointer Dimming: The scan tool displays 0-100 percent. This is the dimming level of the gage pointers of the IPC.

Right Rear Door Ajar Sw: The scan tool displays Door Closed or Door Ajar. The state of the right rear door ajar switch as commanded by the BCM.

Seat Belt Telltale: The scan tool displays On or Off. The state of the fasten safety belt indicator as commanded by the IPC.

Service Engine Soon Lamp: The scan tool displays On or Off. The state of the service engine soon indicator as commanded by the IPC.

Service Vehicle Soon Lamp: The scan tool displays On or Off. The state of the service vehicle soon indicator as commanded by the IPC.

TR Sw. A/B/C/P: The scan tool displays HI or LOW on four signal circuits to the PRNDL in the center console. The state of the PRNDL indicator as commanded by the BCM.

Transmission Range: The scan tool displays First Gear, Second Gear, Third Gear, Fourth Gear, Fifth Gear, Park, Reverse, Neutral, Drive, and Invalid. The state of the PRNDL indicator as commanded by the IPC.

Vehicle Speed: The scan tool displays 0-255 km/h (0-155 mph). The IPC monitors the vehicle speed signal circuit from the PCM via serial data.

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