How to Replace the Battery in an Older Mercedes-Benz C240 4MATIC Key?

[AlyssaAnn]

Mercedes-Benz car keys are not related to specific models or series. In other words, keys for C-Class, E-Class, and S-Class vehicles from the same era are basically identical, and the battery replacement method is largely the same. 1. Flip open the tab at the rear end of the key to remove the mechanical key. 2. Insert the mechanical key into the side slot of the key housing and press the internal gray button. 3. With your other hand, push the rear end of the key upward. When a gap opens, you can remove the mechanical key. 4. Then manually pull out the rear end to access and replace the battery. 5. After installing the new battery, reinsert the key holder to complete the battery replacement process.