B1271

DTC B1271

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B1271
- Theft Locked

Circuit/System Description

This DTC is generated by the module when the theft lock is activated. This occurs when the VIN as received over the class 2 communication circuit and the VIN as stored in the module memory do not match. This also occurs when no VIN is received over the class 2 circuit. The only circuit required is the class 2 communications line.

Conditions for Running the DTC

This test is run every 300 milliseconds.

Conditions for Setting the DTC

This DTC is generated by the module when the VIN as received over the class 2 communication circuit and the VIN as stored in the module memory do not match. This also occurs if no VIN is received over the class 2 circuit. This DTC test runs when the radio changes from OFF to ON.

Action Taken When the DTC Sets

The radio does not function. The radio will display Locked - THEFTLOCK Active.

Conditions for Clearing the DTC

Re-calibration with the correct calibrations for the vehicle and cycling the radio to OFF then to ON will clear the DTC if there is no damage to the radio.

Circuit/System Testing

Ignition ON the ignition, with the engine OFF. With a scan tool, clear the radio theft information and DTC. Cycle the ignition and verify the DTC did not reset.

If the DTC resets, replace the radio.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests