Diagnostic Instructions
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
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.
- Ignition ON, select Reset ECU on the scan tool for the CIM.
- 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