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.

### DTC Descriptor

DTC B3902 00: No Immobiliser Identifier Learned

### Circuit/System Description

When certain modules are programmed and configured during installation, the module learns a specific immobilizer identifier which is unique to the vehicle. The immobilizer identifier is used as a means to discourage vehicle theft by means of swapping modules between vehicles.

The steering column module (CIM) is the keeper of the immobilizer identifier. The instrument panel cluster (IPC), underhood electrical center (UEC), and rear electrical center (REC) each learn the immobilizer identifier during their configuration process. During vehicle operation, each of these modules compare their immobilizer identifier to the CIM. If the identifiers match, vehicle starting is allowed. If an immobilizer identifier does not match, vehicle starting is disabled.

### Conditions for Running the DTC

Ignition ON

### Conditions for Setting the DTC

An incorrect immobilizer identifier is received by the control module

### Action Taken When the DTC Sets

• | Vehicle starting is disabled

• | The Service Vehicle Soon indicator will flash

### Conditions for Clearing the DTC

• | A current DTC will be cleared when the module learns an environment identifier.

• | A history DTC will clear after 100 malfunction free ignition cycles.

### 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

Important: When reprogramming a control module which has already been programmed, additional security measures must be met before reprogramming is allowed. Prior to programming, security access must be granted by connecting a Tech 2 in a pass-thru arraignment and requesting security access in TIS. Once security access is granted, the security code must be entered. The security code can be found in DealerWorld. Both of these security measures must be met before the Reset ECU selection is allowed.

1. Ignition ON, select Reset ECU on the scan tool for the CIM.
2. Perform the Programming and Setup procedure for the CIM. Refer to Control Module References for programming and setup procedures. Verify the DTC does not reset after programming.

⇒ | If the DTC resets, replace the CIM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for CIM replacement, setup, and programming