• | 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. |
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 to prevent swapping modules between vehicles. The body control module (BCM) is the keeper of the immobilizer identifier. The instrument cluster, electronic brake control module (EBCM), and HVAC control module each learn the immobilizer identifier during their configuration process. During vehicle operation, each of these modules compare their immobilizer identifier to the BCM. If the identifiers match, vehicle starting is allowed. If an immobilizer identifier does not match, vehicle starting is disabled.
Ignition is in the ACCESSORY or RUN position.
An incorrect immobilizer identifier is received by the control module.
• | The security indicator in the instrument cluster will illuminate. |
• | Vehicle starting will be disabled. |
A current DTC will be cleared when the module learns an environment identifier.
Immobilizer Description and Operation
Control Module References for scan tool information
⇒ | If the DTC resets, replace the concerned control module. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for Instrument Cluster, body control module and electronic brake control module replacement, setup, and programming