Five Common Lock Problems and Safe First Checks
Simple observation can identify a door-alignment or battery problem, but forcing, disassembling or resetting a lock can make the situation worse. Stop when a check requires access you do not have or changes stored settings.
A key is difficult to turn
Try the best available original key and observe whether pushing or lifting the door changes the symptom. Do not apply more force. Wear, debris and strike misalignment require different corrections.
A key broke in the cylinder
Do not push the fragment deeper or add glue. If a piece projects far enough to grip without turning the mechanism, careful removal may be possible; otherwise protect the opening and request extraction.
A smart lock is unresponsive
Check the documented battery procedure and physical key override. Do not factory-reset the lock unless you have administrator access, setup information and another way to enter, because a reset can remove codes and integrations.
The cylinder spins
Stop using the lock. Loose mounting or a disconnected tailpiece may be involved, and continued turning can leave the door unable to lock or unlock.
The deadbolt misses the strike
Check for loose hinges, door movement and weather stripping before changing the strike opening. Seasonal movement may reveal a frame or installation issue rather than a failed deadbolt.
For a persistent problem, see home lock repair.