How To Open Bmw Key Fob To Change Battery. Find the small hole around the edge of the fob and use it to pry off the backplate. Bmw designed the key fob to be the only tool you'll need to remove the battery.

The bmw key battery is located under the back cover. Hold the button at the base of the fob and slide out the internal key blade. To do so, hold your new key fob flat against the low key battery indicator on the side of the steering column.
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Either Slide The Key Out Or Spring It Away From The Fob.
Press the small tab that can be found on the key fob and pull to get the valet key out press the small tab in the key fob and pull to remove the valet key. Now take the working key fob and hold down the unlock button. (try to ensure the battery change over is all done within 60 seconds or earlier) to save having to reprogramme etc.type 2 doesn't require replacement batteries as these are rechargeable and must be done by using each key once a year to recharge.
Then Hold The Start/Stop Button Until The 'No Key' Warning Light Disappears.
Listen for a lock sound. With the latter held down, press the bmw logo three times. Bmw designed the key fob to be the only tool you'll need to remove the battery.
Place The New Bmw Key Battery In The Place Of The Old Battery.
Now take the working key fob and hold down the unlock button. Turn the key back and remove it. Find the small hole around the edge of the fob and use it to pry off the backplate.
Install The New Bmw Key Battery.
You have to open the key, although in some fobs the key is removable. It should not require resync after a battery change, especially when old battery still had good voltage. Replace the batteries inside the key fobs.
Activating Your Bmw Remote Key Fob.
You’ll hear a small click and the dash lights will turn on, but the engine shouldn’t turn over. Press it and pull off the top of the fob, revealing the key. If your bmw key fob's battery has run out, you won't be able to unlock your vehicle remotely or, if your bmw has comfort access, use keyless entry.