For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### Circuit/System Description

The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the engine control module (ECM). The IPC receives a serial data message from the ECM indicating the engine coolant temperature.

### Reference Information

#### Schematic Reference

• | Instrument Cluster Schematics

• | Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Instrument Cluster Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Ignition ON, perform the engine coolant gage sweep test with the scan tool, verify that the engine coolant temperature gage sweeps from its low to high position.

⇒ | If the engine coolant gage does not sweep, replace the IPC.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for the IPC replacement, setup, and programming