B1271 Code: Meaning, Causes, and Symptoms | OBD2 Codes
B1271 – Theft Protection Active
B1271 Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
B1271 Possible Causes
Reprogram Control Module,Faulty Control Module,Control Module harness is open or shorted,Control Module circuit poor electrical connection
When the Control Module is initially installed in the vehicle, the Control Module receives Vehicle Identification Number (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.