Car Key Snapped in the Lock? What to Do
Leave it alone. A broken key in a lock is normally a straightforward extraction, but most of the expensive damage on these jobs is caused by the recovery attempt rather than the break. If the fragment is protruding enough to grip cleanly with your fingers, try once. Beyond that, stop.
What not to do
- Do not use superglue. It is a common instinct and it reliably destroys the lock, turning a small job into a replacement.
- Do not push the other half of the key back in. It drives the fragment deeper.
- Do not try to turn the fragment with a screwdriver or blade. This is how barrels get wrecked.
- Do not keep going with tweezers after two failed attempts — each one tends to move the piece further in.
- Do not force the door or window as an alternative. The lock is the cheaper repair.
Why keys snap
Metal fatigue. A key flexes very slightly every time it turns, and after years of that a crack develops — usually at the shoulder where the blade meets the head. It rarely happens without warning.
A stiff or worn lock accelerates it, because more force goes through the blade on each turn. If your key had been getting harder to turn, that was the warning.
How extraction works
Purpose-made extraction tools grip the broken piece and draw it back out along the keyway, without disturbing the wafers inside the lock. Done properly it leaves the lock exactly as it was.
Afterwards the lock is checked, and then there is the separate question of getting you a working key — a repair if the blade is a replaceable part, or a fresh key cut to the vehicle.
Should the key be copied or cut fresh?
Cut fresh to the vehicle, not copied from the remaining half. Copying reproduces the wear that caused the break in the first place, which means you are buying the same failure again on a delay.
Door, boot or ignition: why the location matters
- Door lock
- Usually the most straightforward extraction. The car can still be opened from another door or the remote in the meantime.
- Boot lock
- Similar to a door, though some boot locks are harder to reach and may need the trim panel removed.
- Ignition
- The most delicate. The barrel may also house the aerial that reads the key’s chip, and damage there can create an immobiliser fault on top of the broken key.
If the broken piece is flush or pushed in
If part of the blade is still sticking out, it can sometimes be drawn out with care. If it is flush with the face of the lock or has been pushed further in, stop. Every further attempt risks packing it deeper against the wafers, which is what turns an extraction into a lock replacement.
Do not use glue. It runs into the mechanism and sets the fragment in place.
Once the piece is out, deal with why it broke. A key that snapped under normal use was usually worn, or the lock was stiff — and a copy of the worn key will fail the same way.
Common questions
Will the lock need replacing?
Usually not, if nothing has been forced. Most locks survive a clean extraction without any lasting effect.
Damage tends to come from what was tried before the locksmith arrived.
Can the broken key be repaired?
Sometimes, particularly on flip keys where the blade is a separate replaceable part and the electronics are untouched.
Keep every piece, including whatever comes out of the lock.
It snapped in the ignition rather than the door. Is that worse?
Not necessarily, though access is tighter and the steering lock may be engaged.
Mention which lock it is when you call, because it affects the approach.
Key snapped?
Leave it as it is and call. Tell us which lock and how much is protruding.