BMW M5 key fob battery
3 of the 22 model years listed for the BMW M5 have a proven battery. The most common answer is Rechargeable. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.
- 2000Key-head remote
Not confirmed yet
- 2001Key-head remote
Rechargeable
Owner's manual: manualslib.com (checked Nov 2, 2026)
Manual text: “battery in every master key which is charged automatically”
- 2002Key-head remote
Rechargeable
Two sites agree: manualslib.com and fruugo.us (checked Nov 1, 2026)
- 2003Key-head remote
Not confirmed yet
- 2006-2007Key-head remote
Not confirmed yet
- 2006-2010Smart key
Not confirmed yet
- 2008Key-head remote
Rechargeable
Owner's manual: manualslib.com (checked Nov 1, 2026)
Manual text: “Each remote control contains a battery which is charged in the ignition lock”
- 2009-2010Key-head remote
Not confirmed yet
- 2012-2016Smart key
Not confirmed yet
- 2018-2020Smart key
Not confirmed yet
- 2021-2025Smart key
Not confirmed yet
Changing the battery
Key with remote in the head
- The remote electronics sit in the plastic head of the key itself, so there is no separate fob to open.
- Find the seam around the head. Twist a coin or small flat screwdriver in the notch at the blade end or side until the halves part.
- Inside you may find a small circuit board in a tray. Lift the board out if the cell is underneath, swap the cell with the same side up, and refit the board.
- Press the head together until it clicks and test the buttons. The transponder chip that lets the car start is separate from the battery, so starting should not change.
The owner's manual says this remote has a rechargeable cell. It charges while the key is in the ignition or the car is driven. There is no coin cell to buy; if it no longer holds a charge, a dealer replaces the remote.
Keep spare coin cells away from small children. A swallowed coin cell can burn the throat within hours; if it happens, go to an emergency room at once.