For 1990-2009 cars

### Displays Test

Certain instrument panel cluster (IPC) features are tested when the ignition is turned on in order to verify that the features are working properly.

• | All gages will perform a full sweep upon transition from CRANK to RUN.

• | The following indicators illuminate briefly at key up unless otherwise noted:

- | ABS

- | Air bag - flashes 7 times

- | Brake Warning Lamp

- | Charge indicator - stays on in RUN or engine OFF

- | Coolant temp

- | Cruise - no bulb check when ACCA present

- | Fasten safety belt - flashes only if driver seatbelt unbuckled

- | Low oil pressure indicator

- | Malfunction indicator lamp (MIL)

- | Security

- | Traction off

- | Low Tire Pressure - only with TPM equipped vehicles

### Indicators and Warning Messages

Refer to Indicator/Warning Message Description and Operation .

### Engine Coolant Temperature Gage

The engine control module (ECM) sends the coolant temperature to the instrument panel module (IPM) via GMLAN. The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the IPM. The IPC receives a GMLAN message from the IPM indicating the engine coolant temperature. The engine coolant temperature gage, if equipped, defaults to a minimum when:

• | The ECM detects a malfunction in the engine coolant temperature sensor circuit.

• | The IPC detects a loss of GMLAN communications with the IPM.

• | The IPC detects a loss of GMLAN communications with the ECM.

Refer to Cooling System Description and Operation .

### Fuel Gage

The engine control module (ECM) sends the fuel level information to the instrument panel module (IPM) via GMLAN. The instrument panel cluster (IPC) displays the fuel level as determined by the IPM. The IPC receives a GMLAN message from the instrument panel module (IPM) indicating the fuel level percent. The fuel gage defaults to empty if:

• | The ECM detects a malfunction in the fuel level sensor circuit.

• | The IPC detects a loss of GMLAN communications with the IPM.

• | The IPC detects a loss of GMLAN communications with the ECM.

When the fuel level is less than a predetermined value, the low fuel message displays in the driver information center (DIC). For more information, refer to Evaporative Emission Control System Description for the 2.8L, 3.0L, 3.2L or 3.6L engines, Evaporative Emission Control System Description for the 4.6L engine.

### Odometer

The engine control module (ECM) sends the vehicle mileage and trip mileage to the instrument panel module (IPM) via GMLAN. The instrument panel cluster (IPC) displays the odometer mileage and trip mileage as determined by the IPM. The IPC receives a GMLAN message from the IPM indicating the odometer mileage and trip mileage. The odometer will display 'error' if an internal IPC memory failure is detected and DTC B1000 is set.

### Speedometer

The engine control module (ECM) sends the vehicle speed to the instrument panel module (IPM) via GMLAN. The instrument panel cluster (IPC) displays the vehicle speed as determined by the IPM. The IPC receives a GMLAN message from the IPM indicating the vehicle speed. The speedometer will default to zero if:

• | The ECM detects a malfunction in the vehicle speed sensor circuit.

• | The IPC detects a loss of GMLAN communications with the IPM.

• | The IPM detects a loss of GMLAN communications with the ECM.

### Tachometer

The engine control module (ECM) sends the engine speed to the instrument panel module (IPM) via GMLAN. The instrument panel cluster (IPC) displays the engine speed as determined by the IPM. The IPC receives a GMLAN message from the IPM indicating the engine speed. The tachometer will default to zero if:

• | The ECM detects a malfunction in the engine speed signal.

• | The IPC detects a loss of GMLAN communications with the IPM.

• | The IPC detects a loss of GMLAN communications with the ECM.