Theft Protection ON mode is active when a valid vehicle identification number (VIN) has been stored in the radio and the last reported VIN matches. Any time the VIN is reported it is compared to the stored VIN.

Theftlocked mode is active when a valid VIN has been stored in the radio and the last reported VIN does not match. Theftlocked mode is also active when a valid VIN has been stored in the radio and no VIN has been reported since battery power was supplied to the radio.

Stores a DTC B1780 in the IRC memory.

Radio displays Locked -- THEFTLOCK Active when the radio is turned on.

This DTC automatically clears when the radio receives the correct production sequence number (last six digits of the VIN) from the dash integration module (DIM) via Class 2 serial data line.

Problems may arise when the dash integration module (DIM) is replaced and not re-initialized in the vehicle. If it is suspected that the DIM has been replaced, try performing the scan tool SETUP NEW DIM procedure using the scan tool DIM special functions menu. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. If the VIN reported by the DIM does not match the vehicle actual VIN, the VIN may be entered into the DIM manually by following the NEW VIN procedure in the scan tool DIM special functions menu.

The numbers below refer to the step numbers on the diagnostic table:

1. Perform the Radio/Audio System Diagnostic System Check before continuing with the diagnosis of this DTC.

2. Clear all DTCs and cycle ignition to check that the DTC did not falsely set.

7. Clear all DTCs after the repair procedure is complete.