What Are the Reasons Why a Car's Mechanical Key Cannot Open the Door?

[LeJeffrey]

Mechanical key cannot open the door for the following reasons: 1. Incorrect operation—wrong direction of turning the key. In most cases, turning the key clockwise unlocks the door, while turning it counterclockwise locks it. 2. The lock cylinder is faulty. Most car owners use remote keys to unlock or lock the door, rarely using the mechanical key. The keyhole may rust due to prolonged disuse. You can try adding some engine oil into the lock cylinder to lubricate it and see if it can be opened. If it still doesn’t work, the lock cylinder may need to be replaced. 3. The mechanical key is faulty. In most cases, the mechanical key doesn’t have major issues, but if there is a problem, it might be due to a poorly duplicated key.