How to Replace the Battery in an Old BMW X3 Remote Key?

[LaFelix]

Steps to replace the battery in an old BMW X3 remote key are as follows: 1. There is a small switch in the upper-middle part of the back of the key. Gently press it to remove the mechanical key. 2. Use the mechanical key to open the key cover by inserting it into the notch next to the key and gently prying it open. 3. Remove the key compartment cover to reveal the position of the old battery. 4. A small flat-head screwdriver can make it easier to remove the old battery. 5. When installing the new battery, ensure the positive side is facing up. 6. Reassemble the key cover and mechanical key. 7. Test the lock button and other functions to ensure they work properly.