For 1990-2009 cars

## Change Engine Oil Indicator Always On LHD

### Diagnostic Fault Information

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

### Circuit/System Description

The engine control module (ECM) determines when the engine oil should be changed and calculates the oil life in percent. The ECM sends this information via high speed GMLAN to the body control module (BCM). The instrument panel cluster (IPC) receives this information from the BCM through low speed GMLAN and illuminates the oil level percent in the driver information centre (DIC). The IPC will illuminate the CHANGE ENGINE OIL message when the oil needs to be changed.

### Reference Information

#### Schematic Reference

Instrument Cluster Schematics

#### Connector End View Reference

Component Connector End Views

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References

### Circuit/System Verification

1. Verify the scan tool Engine Oil Life Remaining parameter is greater than 0 percent.

⇒ | If equal to 0 percent, reset the engine oil life.

2. If the percent value is normal, replace the IPC.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for PCM or IPC replacement, setup, and programming.