Smart Lock Dead Battery? How to Get In and What to Change

If your smart lock’s batteries die, most models give you a backup: a physical key cylinder, or emergency power contacts where you can hold a battery (often a 9-volt) to wake the keypad. Check your model’s manual. Once inside, replace all the batteries at once with fresh ones.

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A dead smart lock is stressful when you’re standing outside, but most models are designed with a way back in. Learn yours now, before you need it, and the next dead battery becomes a minor chore instead of a lockout.

Locked out now

1. Use the key. Many smart deadbolts still have a key cylinder, sometimes hidden behind a cover.
2. Emergency power. Some keypads have contacts on the bottom or front where you hold a battery to power the keypad long enough to enter your code. Your manual shows if your model has this and which battery to use.
3. Another door. Check whether a garage or back door is open before calling for help.
4. Call a locksmith if none of those work. Forcing the door usually costs more than an opening.

Change the batteries

1. Open the battery cover on the inside unit.
2. Replace all the batteries at once with fresh ones of the type the manual lists. Don’t mix old and new.
3. Check the direction of each battery.
4. Close the cover and test with the door open, then closed.
5. Check that your codes and settings are still there. Most locks keep them, but check.

Low-battery warnings

• Many locks beep, flash or show an alert in the app when batteries are low. Look up what your model’s lights and beeps mean in the manual.
• Don’t wait for a dead lock. Change the batteries at the first warning.
• A lock that drains batteries quickly may be working too hard against a binding bolt. Check the line-up in smart lock won’t lock.
• Note the battery type and the date you changed them.

Make a plan

Keep a spare key somewhere safe outside the house or with someone you trust, and know where your lock’s emergency power option is. For other issues, see smart lock not working. Bill’s video above shows how an electronic deadbolt is installed, including where the battery pack sits.

Quick checklist

• Know where your key or key override is
• Know whether your keypad has emergency power contacts
• Change all batteries at the first low-battery warning
• Use the battery type your manual lists
• Write down the date you changed them
• Test the lock with the door open after every change