How to Replace the Battery in a BMW 1 Series Key?
2 Answers
Method for replacing the battery in a BMW 1 Series key: 1. Press the switch on the back of the key to remove the mechanical key; 2. Insert the removed mechanical key into the small hole on the side of the key to open the key cover; 3. After prying open the key cover, the old battery inside will be visible; 4. Use a small flat-head screwdriver to remove the depleted battery; 5. Ensure the new battery is placed with the positive side facing up; 6. Reassemble the key in reverse order; 7. Test the key functions to ensure they are working properly. The BMW 1 Series key has three buttons: lock, trunk open, and unlock. Holding down the unlock button can simultaneously lower all four windows, while holding down the lock button can simultaneously raise all four windows.
The first time I changed the battery for my BMW 1 Series key fob by myself, I was a bit flustered, but found it actually quite simple. First, locate the small notch on the back of the key—use a coin or thin screwdriver to gently pry open the battery compartment cover. The battery is a round, coin-shaped CR2032. When removing the old battery, be careful not to damage the internal circuit board. When inserting the new battery, pay attention to the polarity—usually the side with the lettering faces upward. After securing the cover, press the key buttons to test if the remote function is restored. If there’s no response, the battery might be inserted backward or there could be dust on the contacts. It’s recommended to clean the notch before each battery replacement to avoid malfunctions. The key fob battery typically lasts one to two years—if you notice the remote range shortening, it’s time for a replacement. DIY battery swaps cost just a few bucks for the battery, much cheaper than visiting a repair shop, plus you pick up a handy skill. The whole process takes at most five minutes—just remember to choose a reliable battery brand when purchasing.
