What Causes a Key to Insert but Fail to Unlock?
1 Answers
Excessive key wear. Below are the detailed explanations: Key grooves: The key has grooves that push open the spring plates inside the keyhole. When all grooves are properly aligned, they form a straight cut, allowing the key core to rotate smoothly and unlock the door. Excessive wear: However, if the key is excessively worn, the spring plates may not be pushed open enough to form a straight cut, causing the plates to jam the lock cylinder and prevent rotation. This is typically the result of prolonged key usage. In such cases, only a spare key can be used to open the door. Regularly injecting lubricating powders like graphite into the keyhole can reduce friction and minimize key wear.