Mercedes-Benz C-Class key battery
W206
2021–2024- Smart keyCR2032
How to change a smart key battery
- Slide the release catch and pull out the emergency key blade.
- Wrap the tip of a small flat screwdriver in tape or a cloth, put it in the slot the blade leaves and twist gently to part the case. Keep it off the circuit board and contacts.
- Note which way up the old cell sits before you lift it out. It varies by key, so don't assume + is up.
- Fit a new CR2032 the same way up, holding it by the edges. Leave any grease on the contacts.
- Clip the case back together and test the buttons at the car. Most keys work straight away with no reprogramming.
- Keep new and old cells away from children. A swallowed button battery can cause serious injury within two hours.
W205
2014–2021- Smart keyCR2032
How to change a smart key battery
- Slide the release catch and pull out the emergency key blade.
- Wrap the tip of a small flat screwdriver in tape or a cloth, put it in the slot the blade leaves and twist gently to part the case. Keep it off the circuit board and contacts.
- Note which way up the old cell sits before you lift it out. It varies by key, so don't assume + is up.
- Fit a new CR2032 the same way up, holding it by the edges. Leave any grease on the contacts.
- Clip the case back together and test the buttons at the car. Most keys work straight away with no reprogramming.
- Keep new and old cells away from children. A swallowed button battery can cause serious injury within two hours.
W204 facelift (Mopf)
2011–2014W204 (saloon)
2007–2014North American models
W203 (saloon)
2001–2007- Remote head key2 × CR2025
Takes two cells. Replace both at the same time, stacked the same way as the old ones.
For locksmiths · W206
- KeysSmart key
- Tools confirmed9
- Transponder chipSubscribers
- Programming procedureSubscribers
Questions
Mercedes-Benz C-Class key battery questions
W206 (2021–2024): CR2032 in the smart key. W205 (2014–2021): CR2032 in the smart key. W204 facelift (2011–2014): CR2025 in the remote head key and smart key. W204 (2007–2014): CR2032 in the remote head key and smart key; CR2025 in the remote head key and smart key.