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How To Replace a Battery in a Car Key Fob

Welcome to! Home of the best guides on programming replacement keys and changing a dead battery in your car’s key fob.

Replacing Key Fob Batteries

Scott founder @
I made first ~100 battery change videos. Then Kevin took over!

Kevin and I have made more than 600 unique videos, pics, and guides on how to switch car fob batteries since 2017. The most popular car key fob battery is a CR 2032 (amazon link) – it’s pretty much the go-to battery around the world. The numbers represent the size of the battery – 20mm wide and 3.2mm tall. The C stands for lithium chemistry, and the R stands for its round shape.

Other popular “button batteries” for key fobs include the CR2450, VL2020, CR2025, CR1616, and CR2016. Check out our YouTube channel for our latest video guides. We’ve gone through tons of different car key fobs in the last three decades (90’s-2022) and have completed over 80% of them. We’re aiming to finish up the rest in 2023. We’ve got in-depth tutorials for each one so you’ll be good to go!

Programming A Car Key Replacement

Our other major guides and DIY section is about how to program new or replacement car keys. With new at-home kits, you can now program a new car key replacement for under $100 for many models. We will be adding new guides and videos as we build out this section in 2023.