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 cluster displays the engine coolant temperature, vehicle speed and the engine speed based on the information from the engine control module (ECM). The ECM sends appropriate information via a High Speed CAN-Bus signal to the body control module (BCM). The BCM then sends the information via a Low Speed CAN-Bus signal to the instrument cluster to display the engine coolant temperature, the engine speed, the vehicle speed and the distance travelled, either in kilometers or miles, based on the vehicle requirements.

### Reference Information

#### Schematic Reference

Instrument Cluster 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

1. Ignition ON, perform the Instrument Cluster Gauge Sweep test with the scan tool, verify that all gages sweep from their low to high position.

⇒ | If any gage does not sweep, replace the P16 Instrument Cluster.

2. Drive the vehicle, verify the odometer display, the displayed distance counts up while driving.

⇒ | If the odometer display does not count up, replace the P16 Instrument Cluster.

3. If all gages do sweep and the odometer display counts up, replace the K20 Engine Control Module (ECM).

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for the Instrument Cluster or ECM replacement, setup, and programming