These instructions apply to the BMW X5 Mk2 (E70) 2006-2013.
For other models, please choose your vehicle here.
A weak remote or “key battery low” message on the BMW X5 (E70, 2006–2013) usually means the fob battery is flat — but first check which key you have, because the keyless Comfort Access fob is rechargeable and has no replaceable battery.
How to Replace the X5 (E70) Key Fob Battery
- Slide out the metal emergency key blade from the fob (press the release and pull).
- Remove the key-blade cover / open the fob case at the seam.
- Lift out the old CR2450 coin cell.
- Fit the new cell with the positive (+) side facing up, as the old one sat.
- Close the cover and slide the emergency key back in, then check the remote works.
Comfort Access (Keyless) Keys Are Different
If your X5 has Comfort Access keyless entry, that fob is rechargeable — there’s no coin cell to change. It tops up its charge while you drive (and on older designs, when slotted into the ignition). If it goes flat, hold it against the start button to start, then let the car recharge it.
Frequently Asked Questions
What battery does the BMW X5 E70 key take?
The standard remote uses a CR2450 3V coin cell, fitted positive-side up. Comfort Access keyless fobs are rechargeable and have no replaceable battery.
Do I need to reprogram the key after changing the battery?
No — a battery swap doesn’t affect programming. A lost or replacement key must be ordered from a dealer and coded with a diagnostic tool.
Remote still dead with a new battery?
Use the emergency blade to unlock, then hold the fob against the start button to start, and have the key checked.
For a related key or immobilizer code, see autodtcs.com.
Independent guide — not affiliated with BMW. Always follow your official service manual and safety precautions. Read our full disclaimer.