TTLock Auto Lock Not Working: Why and How to Fix It

Auto lock is a timer that runs on the lock's own firmware: once the door is unlocked or the bolt retracts, the lock waits a configured number of seconds and then relocks automatically. Because the timer and its behaviour live entirely on the lock, not in the app, several things can quietly break it.

• The new setting never synced to the lock. Changing the auto lock delay in the app only queues the change; it has to be pushed to the lock over Bluetooth before it takes effect. A phone that never gets back in range leaves the lock running its old setting, or none at all.
• Passage mode is turned on. Passage (or "always open") mode deliberately keeps the lock unlocked for extended access, and it overrides auto lock by design — the lock is not malfunctioning if it stays open while this mode is active.
• No door sensor, on models that support one. On some deadbolt-style locks, auto lock timing can depend on the lock knowing the door is actually closed via a magnetic sensor; without one fitted, the lock may fall back to a fixed timer or behave inconsistently.
• The bolt or latch is obstructed. A misaligned strike plate, a swollen door frame, or debris in the bolt path can stop the motor from fully extending. Many locks refuse to report a successful lock, or retry and give up, in that situation.
• Low battery. As batteries weaken, some locks disable auto lock (which draws extra motor power on a timer) as a protective measure, or the motor loses enough torque that the bolt never fully seats.

1. Open the lock's settings and confirm auto lock is enabled with a delay set. Re-select the delay even if it already looks correct, to force the app to resend it.
2. Stay within Bluetooth range while the setting saves. Wait for the app to confirm the change reached the lock rather than closing the screen immediately.
3. Check whether passage mode is active. Turn it off if the door is supposed to relock automatically; passage mode and auto lock are mutually exclusive behaviours.
4. Test the bolt manually. Lock and unlock the door by hand and feel for resistance, grinding, or a bolt that doesn't fully extend into the strike plate.
5. Adjust the strike plate or door alignment if the bolt binds. Even a couple of millimetres of misalignment is enough to make an auto lock motor give up.
6. Replace the batteries with a fresh, matched set. Use lithium AA cells where supported; they hold voltage better under the motor's load than alkaline.

On locks that support an external door sensor, auto lock can be configured to wait until the sensor reports the door as closed before starting or completing the relock, which prevents the bolt from repeatedly striking an open door. If your model has this option and the auto lock never engages, check that the sensor is paired, has working batteries, and is mounted close enough to the frame magnet to register "closed" reliably.

Smart Lukko is an independent third-party app for TTLock-compatible smart locks and is not affiliated with TTLock or Sciener; auto lock timing, motor behaviour and sensor support are determined by each lock manufacturer's hardware.

• Shorten the delay temporarily to test. Set auto lock to its shortest interval to quickly confirm whether the timer runs at all, before troubleshooting a longer delay that's simply slow to notice.
• Check for a scheduled access mode. Some locks let passage mode be scheduled for certain hours; auto lock will appear to work sometimes and not others if a schedule is quietly active.
• Rule out battery drain as the underlying cause. If auto lock stopped around the same time the battery indicator dropped, replacing batteries and re-testing is worth doing before anything else.
• Confirm the setting on the lock, not just in the app. If a factory reset or a second admin changed settings directly, the app's displayed value can be stale until it re-syncs.