Use the following procedure to repair lock cylinders frozen by cold weather:

Important: Be careful not to damage painted surfaces while using a heat gun.

1. Apply heat to the cylinder area with a heat gun.
2. Using compressed air and a blow gun attachment, hold the shutter door open with a paper clip or similar item and force the air into the lock cylinder.
3. Hold the shutter door open and inject a small amount of the Multi-Purpose Lubricant GM P/N 12346241 or the equivalent into the lock cylinder.
4. Work the key into the lock cylinder several times and wipe any excess lubrication residue from the key and the lock cylinder.