Go to https://www.mrlocksmith.com to learn more. How to Unfreeze a Frozen Car Lock Video. When the thermometer dips below freezing temperatures at Mr. Locksmith (604-782-6996) we receive calls from customers who are locked out of their cars because the car door lock is frozen. Note: the most common cause of frozen car locks is the customer washed their car and not only is the car lock frozen but the entire door. Most of the time only a small amount of water has entered the car lock via the key hole. Do not pour hot water over your car door and car lock.” Boiling water may or may not work but the hot water may damage the door lock and seals. Also, the water will freeze again this time in the lock and linkage. I have found the best method to loosen up the frozen lock is using a spray “Lock De-icer” is available at most Automotive Stores. www.mrlocksmith.com