How to Replace the Battery of the Mercedes Key Fob?

by Phil Borges // in Car

If you happen to be one of the proud owners of a Mercedes, then one of your favorite things to do is probably driving it. Driving a Mercedes can be an enjoyable experience, but there are some maintenance tasks that you need to take care of too. One such task is replacing the battery in your key fob remote control.

If you are in a hurry to find out how to replace the battery of your Mercedes Key Fob, look no further as we will show you the step by the step procedure.

How to replace the battery of the Mercedes Key Fob?

If you have a Mercedes key fob and the battery is not holding a charge, it can be really frustrating. But luckily for you, we’ve got some steps to take to replace the battery of your Mercedes Key Fob.

1) Remove the hard key from the key fob. You will use this hard key to pull out the back cover of the key fob.

2) Use the back part of the hard key to swipe from left to right underneath the key fob until the cover tab pops off.

3) Remove the old battery and replace it with a new one. This key fob uses a lithium battery CR2025 which you can find in any store that sells batteries. Just make sure that the orientation of the battery is correct when inserting it in the battery compartment.

4) As soon as the new battery is in place, reattach the cover back onto the key fob, and it should be good to go!

If you ever feel uncomfortable changing the battery yourself, bring your key fob to a Mercedes dealer/store, and they will replace the battery for you.

What are the signs that your key fob battery is dying?

Signs that your key fob battery is dying are typically evident in a few different ways. One major sign that you should replace the battery of your Mercedes Key Fob is when it starts to lose contact with the car. Signal strength gets worst, and you might start to lose the ability for your key fob to unlock or lock your car. You may have trouble turning on and off certain features like remote starting, popping open your trunk, or locking/unlocking doors.

Another way that will let you know it’s time to replace the battery of a Mercedes Key Fob is that the device itself is not properly working due to over clicking. This happens when you have to press the button multiple times in order for it to work. If your key fob doesn’t work, it might need to be replaced. If you find yourself pushing the button repeatedly and still don’t trust that the vehicle is locked, this means something may not be working with your car’s locking system or perhaps even within the element of chance itself.

If your key fob works only 90% of the time from a normal distance, it’s still not worth trying to hold off on getting checked. Your battery may need replacing, or you might have forgotten that in order for it to work correctly, each step must be performed properly and at the right timing. When you get the key fob checked out, they may find your battery needs to be replaced, or that programming for the auto keys must be updated. It is still better to have them check why sometimes works and other times doesn’t work.

How to maintain the battery of a Mercedes Key Fob?

Taking care of the battery is an important part of owning a key fob, and all you need to do is change it when necessary. Remember not to let the battery die out completely, as this will shorten its life span and make it depreciate quicker. You should also remove it from any wet or moist areas, as this can cause corrosion on the insides. If you are able to buy a spare battery for your key fob, then that may be another way of keeping your key fob fully charged at all times.

Instead of keeping your key fob in the vehicle overnight, keep it far away from the car. Modern key fobs are constantly communicating with the car as soon as they’re within range; by removing them at night, you can reduce this unnecessary communication and save on battery power for longer life.

It’s extremely important to keep your car fob in a safe location that isn’t exposed to the cold because it can drain its remaining charge. This is why you need to bring your key fob inside overnight.


Your key fob is your gateway to your car and should be handled with care. As you can see, taking care of the battery in a Mercedes Key Fob isn’t too difficult to do as long as the instructions given out in this article are followed. Even if this was not your first time doing it yourself, there are always other reasons to take better care of your key fob.

One way to prolong your key fob is to make sure to clean out all of the dirt from inside before putting in your new battery, as this will help prolong its life and prevent any corrosion on your newly installed battery.

If your key fob is unreliable, it will be harder to lock the car. This can leave you and your possessions exposed to theft if someone breaks into the vehicle without being detected by a motion sensor or alarm system.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.