What Should You Expect When a Smart Lock Battery Dies?

When a smart lock’s battery is completely drained, its electronic features stop working, which means you won’t be able to unlock the door using the app, keypad, or voice assistant. However, here’s what you need to know:

1. The Lock Remains Secure

A common concern is whether a dead battery will cause the lock to disengage, making your home vulnerable. Fortunately, this does not happen. Most smart locks are designed to:

  • Fail in a locked position – This ensures your home stays secure even if the battery dies.
  • Allow manual unlocking from the inside – If you’re inside, you can still open the door using the mechanical thumb-turn.

Takeaway: A dead battery won’t compromise your home’s security—it just means you won’t be able to unlock the door electronically.

2. Smart Features Stop Working

Once the battery dies, you lose access to:

  • Keypad or touchscreen entry – The lock won’t respond to PIN codes.
  • App control – You can’t unlock the door remotely.
  • WiFi/Bluetooth connectivity – The lock won’t communicate with your smart home system.
  • Auto-lock feature – If you rely on automatic locking, the door won’t lock itself.

Takeaway: Your smart lock becomes a manual lock until you replace the battery.

3. You Could Get Locked Out

If you’re outside when the battery dies, you may lose access to your home unless you have:

  • A physical backup key (if your smart lock has a keyhole).
  • A 9V battery for emergency power (if your lock supports it).
  • An alternative entry point (garage, back door, etc.).

Many people only realize their battery has died when they try to enter the house and nothing happens.

Takeaway: To avoid getting locked out, always have a backup access method.

4. Emergency Power Options

Some smart locks come with emergency power contacts that allow you to temporarily power the lock with a 9V battery.

Here’s how it works:
Locate the emergency power terminals (usually at the bottom of the lock).
Hold a 9V battery against the terminals.
Wait a few seconds for the lock to power on.
Enter your PIN code or use the app to unlock the door.

Takeaway: Keep a 9V battery in your car or bag for emergencies.

5. Physical Key Override (If Available)

Many smart locks include a hidden keyhole for backup access.

  • The keyhole may be concealed under a removable cover for security.
  • If your lock doesn’t have a keyhole, you’ll need to rely on an alternative method.

Takeaway: Store your backup key in a safe place and test it periodically to ensure it works.

6. Resetting the Lock After Battery Replacement

Once you insert fresh batteries, the lock should power back on. However, you may need to:

  • Re-sync it with your smartphone app.
  • Reset the time and date (if the lock lost power for too long).
  • Reconnect it to your smart home system.

Takeaway: Follow the manufacturer’s instructions to ensure full functionality after a battery change.

Read also: What Happens If a Smart Lock Battery Dies?