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 main immobilizer function is performed as an interaction between several modules. The process that determines whether the engine may be engaged or not consists of several steps. If the engine start will be disabled a DTC is set and the indicator in the instrument cluster will be turned ON.

### Reference Information

#### Schematic Reference

Immobilizer Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Immobilizer 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, verify that no DTC is set.

⇒ | If a DTC is set, refer to DTC list.

2. Perform the instrument panel special functions All Indicators test using a scan tool. Command the instrument panel lamps ON and OFF. Verify the immobilizer indicator icon turns ON and OFF.

⇒ | Perform the instrument panel special functions All Indicators test using a scan tool. Command the instrument panel lamps ON and OFF. Verify the security indicator icon turns ON and OFF. If the security icon does not turn ON and OFF replace the P16 Instrument Panel Cluster (IPC).

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for instrument cluster replacement, setup, and programming