B1271

DTC B1271

Diagnostic Instructions

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



DTC Descriptor
DTC B1271
- Theft Locked




Circuit/System Description

This DTC is generated by the radio when the vehicle identification number (VIN) received over the class 2 serial data circuit and the VIN stored in radio memory do not match. This DTC will also set when no VIN is received over the class 2 serial data circuit.


Conditions for Running the DTC

* Ignition ON.
* Battery voltage must be between 9-16 volts.



Conditions for Setting the DTC

The DTC will set when the VIN stored in the radio does not match the VIN broadcast over the class 2 serial data circuit.


Action Taken When the DTC Sets

* The radio displays Locked - THEFTLOCK Active.
* The radio will not operate.



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.


Reference Information
Schematic Reference

Radio/Navigation System Schematics (Radio/Navigation System Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Testing

1. Ignition ON, with a scan tool, clear the DTC and the radio theft information.
2. Perform theRadio Programming and Setup (Programming and Relearning) .
3. Cycle the ignition and verify the DTC has not reset.

• If the DTC resets, replace the radio.




Repair Instructions

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


Control Module References (Programming and Relearning) for Radio replacement, setup, and programming