‘Is it hard to replace my key fob's battery?’ [Newbie Guide]

Updated Jun 28, 2021 | Same topic: Beginner's Guide

It’s nowhere as complicated as some people think it is. 

Passenger vehicles these days come with some form of security system, chief of which is keyless entry. That particular feature isn’t even exclusive to the top-spec variant of most car models, being offered as standard equipment on midrange and even the base trim levels as well. 

Car key fob

Keyless entry is pretty much a standard feature on new cars these days

Locking and unlocking your car only takes a simple button press on the key fob, which conceals a radio transmitter that sends a signal to a receiver within the vehicle. No two vehicles of the same make and model share that signal, which means that only you have access to your car at any given time, even with an identical unit parked right beside yours at the mall. 

That’s convenience and safety in one. Of course, the one caveat there is that the mechanism is electronic in nature. It draws power from a battery, which eventually gets run down with repeated use. If the car takes longer than usual to respond to the key fob each time you press the buttons, you’ll know it’s time to have the battery replaced. 

CR2032 battery

Car key fobs commonly use a button-cell battery

In contrast with the rather sophisticated system that secures your car every time you leave it in the parking lot, replacing the key fob’s battery is pretty straightforward. Owing to its small size, the fob likely uses a button-cell battery as its power source, usually a CR2032. And it’s not even particularly difficult to find since it’s available in many hardware stores and watch repair shops. 

Key fob tab

A flat-tipped screwdriver will help you pry the two halves open

At most, the tools you’ll be needing would only be a set of precision screwdrivers. A car’s key fob is composed of two halves joined together by either a screw or a snap-fit mechanism. If yours uses the latter, it will have a small tab between the two halves where you can slot in a flat-tipped screwdriver to pry them open. You might want to take out the physical key first, if it’s possible. 

Key fob interior

Once you've accessed the battery compartment, simply switch out the old battery for a new one

Once you’ve separated the two halves, you’ll find one side holding the battery and electronics compartment. Using the same flat-tipped screwdriver, gently ease out the old battery and insert the new one, taking note of the polarities during installation. Once you’re done, bring the two halves of the fob back together and try to lock or unlock the car using the new battery. 

Find more tips for beginner car owners at Philkotse.com.

Joseph Paolo Estabillo

Joseph Paolo Estabillo


Joseph holds a degree in Journalism from the University of the Philippines Diliman and has been writing professionally since 1999. He has written episodes for CNN Philippines' motoring show Drive, and has worked on corporate projects for MG Philippines and Pilipinas Shell. Aside from being Philkotse.com’s Content Lead, he also writes content for numerous car dealerships in the U.S., spanning multiple brands such as Alfa Romeo, Chrysler, Dodge, Jeep, and Maserati, among others.

Facebook: https://www.facebook.com/kapatilya

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