BMW M2 key fob battery
3 of the 9 model years listed for the BMW M2 have a proven battery. The most common answer is CR2450. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.
- 2016-2017Smart key
Not confirmed yet
- 2018Smart key
CR2450
Owner's manual: manualslib.com (checked Nov 1, 2026)
Manual text: “Insert a type CR 2450 battery with the positive side facing up.”
Find CR2450 on Amazon - 2019Smart key
CR2450
Owner's manual: manualslib.com (checked Nov 1, 2026)
Manual text: “Insert a type CR 2450 battery with the positive side facing up.”
Find CR2450 on Amazon - 2020-2021Unknown
Not confirmed yet
- 2023Smart key
CR2032
Owner's manual: manualslib.com (checked Nov 1, 2026)
Manual text: “Insert a CR2032 3V battery with the positive side facing up.”
Find CR2032 on Amazon - 2024-2025Smart key
Not confirmed yet
Changing the battery
Smart key (push-button start)
- Most push-button fobs hide a metal backup key. Press or slide its catch and draw the key out first.
- 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.
- Before you take the old cell out, look at its face. Put the new cell in with the same side showing, and avoid touching both faces at once.
- Snap the halves back together, slide the metal key home, and press each button, then try the start button from the driver's seat.
A CR2032 is 20 mm across and 3.2 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.
A CR2450 is 24.5 mm across and 5.0 mm thick, much fatter than a CR2032. A thinner cell will rattle and lose contact, so buy the exact size.
Coin cells are a choking and burn hazard for children. Store the spares in their original pack, out of reach.