When a remote key is inserted into the ignition lock cylinder and the ignition is turned ON, the transponder embedded in the remote key is energized by the exciter coils located in the theft deterrent module (TDM) surrounding the ignition lock cylinder. The energized transponder transmits a signal that contains its unique value, which is received by the TDM. The TDM is directly secured to the steering column module (CIM). The CIM compares this unique value to a value stored in memory. If the value is correct, the CIM will request vehicle starting.

Ignition ON

The transponder value measured by the TDM is incorrect or not learned to the vehicle

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

Important: When using this diagnostic, more than one remote key is required to ensure proper diagnosis. If more than one key is not available at the time of service, contact the customer and ask if any other keys can be provided for service.

1. Perform the Vehicle Key Learn procedure. Refer to Replacing Keys .
2. While viewing the appropraite scan tool CIM Transponder-Key Status parameter, turn ON the ignition with each of the available remote keys. The parameter should read Programmed with all available keys.

⇒	If not the specified value, replace the appropriate key. If the DTC resets, replace the CIM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.