Smart locks & keyless entry

Smart lock battery died? How to get in, and why winter makes it worse

A keypad that goes dark is one of the most avoidable lockouts there is. Here is how to get in, and how to make sure it does not happen again this winter.

By Timmy Creighton, founder and licensed locksmith · Major Key Locksmith · October 2026

Getting in right now

1. Use the key. Most smart deadbolts have a key cylinder hidden under a cover or on the front. If yours is in a drawer inside, that is the lesson for next time.
2. Look underneath the keypad. Many locks have two small metal contacts on the outside. Hold a 9-volt battery against them and the keypad wakes up long enough to enter your code once.
3. Look for a USB port. Some locks, including our MK-1, have a USB-C port on the underside. A phone power bank and a cable will power it enough to open.
4. Try the handle. If the deadbolt opens but the door still will not, the lock below the keypad is locked. That is a different problem from the battery, and a very common one.

If none of that works, call us. A daytime house lockout is $250.

Why it happens more in winter

Batteries deliver less power in the cold, and a front door facing the weather gets cold. A battery that was quietly getting weak in October can fail on the first properly cold morning. The motor in a smart deadbolt also has to work harder if the door has shifted and the bolt is rubbing the strike, which is common as frames contract in winter.

The habits that prevent it

• Take the first warning seriously. A blinking red light or a beep on entry usually starts weeks before the battery dies. The door still opens, which is why people ignore it.
• Change batteries on a schedule, not when they die. Fall is a good time, before the cold.
• Use the battery type your lock’s manual specifies. Some locks read low-battery levels incorrectly with the wrong chemistry and stop warning you.
• Keep the physical key somewhere outside the house that you can actually reach: a family member nearby, or your car.
• Fix a bolt that drags. If you have to push or pull the door for the bolt to throw, the strike needs adjusting. A dragging bolt drains batteries and eventually stalls.

Questions people ask

How long do smart lock batteries last?

It varies widely by model, how often the door is used, and whether the lock is on Wi-Fi. Many last most of a year. A lock that eats batteries in a few months usually has a door alignment problem or a constant Wi-Fi connection.

Will my smart lock lock me out if the battery dies?

The bolt stays where it was. If it was locked, it stays locked until you power the lock or use the key. That is why a key backup and emergency power matter.

Can a locksmith open a smart lock with a dead battery?

Yes, usually without damage, through the key cylinder. It is priced like any other lockout.

Keep reading

Any price mentioned here is the one published on our pricing page as of October 2026. The final price is always confirmed with you before any work begins. More answers from the blog →