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Frequently asked questions about cars and motorcycles

How to Replace the Dead Battery in a Mercedes S-Class Key Fob

Model: Mercedes Classe S W221, MK 5 - Years 2005-2013
Part: Key

Let's see how to change the dead battery in a Mercedes S-Class key fob. Take your ignition remote and remove the metal key. Once the metal key is removed, use a screwdriver to pry open the plastic cover. Remove the plastic battery holder (as shown in the video) and the dead battery; take a new one (same size and voltage) and replace it. Reassemble the key fob cover by pressing on the key cover until you hear it click into place. Check the proper functioning of the key fob using the buttons on the key.

Updated on 2 March 2026 by ScegliAuto

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