Mercedes-Benz key fobs use a small battery to power the electronic components, such as the buttons and the keyless entry system. Over time, the battery may need to be replaced. Here’s a guide on how to change the key battery in a Mercedes-Benz:
The key battery is located inside the key fob. To access the battery, you will need to open the key fob. The method for opening the key fob may vary depending on the model of your Mercedes-Benz. Generally, you can open the key fob by pressing a small button on the side of the fob and sliding the two halves of the fob apart.