GM Service Manual Online
For 1990-2009 cars only

Circuit 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 MIL/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.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Entertainment System?

Go to Step 2

Go to Diagnostic System Check - Entertainment System

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool clear the radio theft information.

Does the DTC Reset?

Go to Step 3

System OK

3

Important: Perform the radio setup procedure. Refer to Radio Setup

Replace the radio. Refer to Radio Replacement .

Did you complete the replacement?

System OK

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