How to replace a Car Key Battery in 3 simple steps 


A key fob is a remote which requires battery power to open the vehicle. If your key fob has become temperamental or stopped working altogether, this could be an indicator that the battery inside needs replacing. 

Car Key fobs usually have a round watch style battery inside which powers the key. However, some newer keys are now charged whilst in the ignition of the car, so if they become flat it may be worth seeking additional advice before dismantling the key.


Step 1

Remove the cover:

Most car keys can be prized apart using a flat head screwdriver and working your way around the key until the cover is released. Alternatively, there may be a tiny screw in the bottom of the case which can be undone with a small Philips screwdriver


Step 2 

Identify the battery:

The battery inside will be a round watch style battery and it should have a clear product code engraved on it e.g. CR2032. Ensure you have the correct replacement battery to put back in before you remove the existing battery. In some cases, the car battery will lose synchronization and need reprogramming if left for too long without the battery. With some fobs you can manually reprogram them, however, others may need reprogramming with a specialist diagnostic tool. 


Step 3 

Insert the new battery: 

Remove the existing battery using your fingers or a flat head screwdriver to gently prize it out. Ensuring you have the battery the correct way round, replace with the new one and clip/screw the key fob housing back together.