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Indicator/Warning Message Description and Operation




Indicator/Warning Message Description and Operation














Change Oil

The CHANGE OIL indicator illuminates in the driver information center (DIC) when the powertrain control module (PCM) determines that the engine oil should be changed. The PCM provides a ground for the change oil indicator control circuit in order to illuminate the CHANGE OIL indicator. After the oil is changed, reset the engine oil monitor. Refer to GM Oil Life System - Resetting Testing and Inspection in Maintenance and Lubrication.

Check Gages (L18)

The CHECK GAGES indicator illuminates in the IPC when one of the following occurs:

* The PCM detects that the engine oil pressure is approximately 5 psi (34 kPa) or below.
The PCM monitors the signal circuit of the engine oil pressure sensor.
* The PCM detects that the engine coolant temperature is approximately 107°C (225°F) or above.
The PCM monitors the signal circuit of the engine coolant temperature sensor.

The PCM grounds the check gages indicator control circuit in order to illuminate the CHECK GAGES indicator.

The MFAM receives a direct hardwire input from the PCM and the engine will be shutdown, on vehicles equipped with automatic engine shutdown, when one of the following conditions exist:

* The PCM detects that the engine coolant temperature is at or above 111° C (232° F).
* The PCM detects that the engine oil pressure is at or below 34 kPa (5 psi).

The MFAM grounds the stoplamp switch signal circuit in order to shut the engine down.

Check Gages (LG5)

The CHECK GAGES indicator illuminates in the IPC when one of the following occurs:

* The MFAM detects that the engine oil pressure is approximately 5 psi (34 kPa) or below.
The MFAM monitors the signal circuit of the engine oil pressure switch.
* The MFAM detects that the engine coolant temperature is approximately 107°C (225°F) or above.
The MFAM monitors the signal circuit of the engine coolant temperature switch.

The MFAM grounds the check gages indicator control circuit in order to illuminate the CHECK GAGES indicator.

The engine will be shutdown, On vehicles equipped with automatic engine shutdown, when one of the following conditions exist:

* The MFAM detects that the engine coolant temperature is at or above 111° C (232° F).
* The MFAM detects that the engine oil pressure is at or below 34 kPa (5 psi).

The MFAM provides a ground for the stoplamp switch interface module in order to shut the engine down.

Check Transmission

The Check Transmission indicator illuminates in the DIC when the transmission control module (TCM) detects certain malfunctions in the transmission. The TCM grounds the check trans indicator control circuit in order to illuminate the Check Transmission indicator.

Engine Overspeed

The ENGINE OVERSPEED indicator illuminates in the DIC when the PCM detects that the engine speed range is between 3,600 and 4,000 RPM. The PCM grounds the engine overspeed indicator control circuit in order to illuminate the ENGINE OVERSPEED indicator.

Fasten Safety Belt

The fasten safety belt indicator illuminates in the DIC, for approximately 8 seconds, when the seat belt alarm module detects that the ignition transitions to ON. The seat belt alarm module supplies voltage to the seat belt indicator voltage circuit in order to illuminate the fasten safety belt indicator.

Reduced Engine Power

The REDUCED ENGINE POWER indicator illuminates in the DIC when the PCM detects a malfunction in the throttle actuator control system. The PCM grounds the reduced engine power indicator control circuit in order to illuminate the REDUCED ENGINE POWER indicator.

Service Transmission Filter

The SERVICE TRANS FILTER indicator illuminates in the DIC when the transmission fluid filter differential switch detects a pressure differential increase of approximately 41 kPa (6 psi). The transmission fluid filter differential switch grounds the service trans filter indicator control circuit in order to illuminate the SERVICE TRANS FILTER indicator.