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Home >> GMC >> 2018 >> Acadia SL >> Repair and Diagnosis >> External Pages >> Different car >> Section 331 (Cellular System, Entertainment System, And Navigation System) >> Diagnostic Information and Procedures >> DTC B1271: Theft Protection Active >> Circuit/System Description
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Circuit/System Description

WARNING: This page is about a different car, the 2017 GMC Acadia. However, it is still accessible from the selected car via links, so may be relevant.

When the Control Module is initially installed in the vehicle, the Control Module receives VIN information via serial data. The Control Module stores a portion of the VIN and compares this sequence to the VIN information received each time the Control Module powers on. The VIN in the Control Module is a single one-time learn.

The Control Module theft deterrent system is intended to disable or limit Control Module functionality if incorrect vehicle information is received by the Control Module. The Control Module disables functionality if the VIN information received by the Control Module does not match the VIN information that has been learned by the Control Module. This DTC is generated by the module when the Theft Protection is activated.