If you are reading this, chances are that you are holding the head of a broken key. Usually when keys break it is because people are either torquing them too hard in the lock because they are turning the lock in the wrong direction, the lock is installed improperly, or the lock needs lubrication. When the key breaks, it usually sheers off at the opening of the keyway. It is really terrible when this happens, but don’t forget in your moment of despair: the part that broke off still works. If it is in your ignition, you can probably still turn the car on and drive (as long as the head of the key is really close to the ignition. If it is more than a foot away it most likely won’t turn on or stay turned on past 15 seconds). If the key broke off in your door, you can still unlock the lock by sticking something else in the keyway on the very bottom and continuing the rotation of the cylinder.
Last night I had a client who was locked out of his place due to a key breaking off in his deadbolt, which was both improperly installed and needed to be lubed. Unfortunately his key broke off before he had unlocked either lock, meaning that unless he had a spare key hidden outside somewhere, he was locked out. I turned his deadbolt using a tension wrench for lockpicking inserted above and below the broken key and then picked his knob.
You could replicate my success by sticking pieces of wire in the keyway above and below the key, if there is room, and twisting. In some cases, the key may shear off a little further in the keyway so you can stick a flathead screwdriver in behind the key and turn. Don’t push on the key too hard, or it may push it past where it should be and the pins will be pushed up past the shear line! The broken key must be resting in its natural position.
If the key sheared off sticking out of the lock partially, it can most likely be turned using a wrench or something. As above, be careful not to push the key in or pull it out at all or else the pins will be pushed up past the shear line and the cylinder won’t turn! This problem doesn’t occur when the key is whole because the key is designed to be inserted into the lock until the key’s “shoulder” stops its insertion. That is, the cuts on the key are at standard lengths from the part of the key that stops its insertion; the pins must be centered in those cuts. When they aren’t centered, usually somebody who is lazy or unfamiliar with how to cut a key probably cut your key.
Of course, if you can’t get your lock to turn you can call me. I might be able to save your lock as I did last night, open another door without broken keys in the locks, or I could also drill it out. Best of luck to you in your attempts to get back inside or start your car!
