How to Reset the Tire Sensors on GM Cars
- 1). Press the "Lock" and "Unlock" buttons on your car's key fob at the same time. The car's horn will chirp twice.
- 2). Unscrew the front-left valve stem cap.
- 3). Press on the valve stem for a few seconds to let air out of the tire until the horn chirps. Replace the valve stem cap.
- 4). Repeat Step 3 for the right-front, right-rear and left-rear tires--in this order. The system will be reset, and the TPMS light will shut off.
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