Mercedes-Benz SLS AMG key fob battery
1 of the 5 model years listed for the Mercedes-Benz SLS AMG have a proven battery. The most common answer is CR2025. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.
- 2011-2013Unknown
Not confirmed yet
- 2014Smart key
CR2025
Owner's manual: manualslib.com (checked Nov 1, 2026)
Manual text: “You require a CR 2025 3 V cell battery.”
Find CR2025 on Amazon - 2015Unknown
Not confirmed yet
Changing the battery
Smart key (push-button start)
- Start by freeing the hidden metal key: there is a latch or slide on the case, and the blade comes out once it moves.
- The gap left by the metal key usually has a pry point. A slow twist with a thin flat tool (tape on the tip saves the plastic) opens the two halves.
- Note which side of the old coin cell faces up (usually the side with the writing), lift it out with a plastic tool, and press the new one in the same way.
- Snap the halves back together, slide the metal key home, and press each button, then try the start button from the driver's seat.
On the common chrome Mercedes key, a slide at the back frees the mechanical key, and pushing that key into the opening releases the battery tray.
A CR2025 is 20 mm across and 2.5 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.
Coin cells are a choking and burn hazard for children. Store the spares in their original pack, out of reach.