How to Open the Remote Control of an Old BMW X3?

[DelMolly]

First, press the button on the side to pull out the mechanical key, then insert it into the groove on the back cover. Gently push, and the back cover will pop open. There is no need to disassemble it to replace the battery, as it can be charged using an adapter charging cable or the wireless charging module inside the vehicle's center console.

[Gavin]

I've taken apart the key fob for the older X3 model myself before, and it's actually quite simple. You'll see a thin seam on the side of the key—just use a dime coin or the file from a nail clipper to wedge in there and gently pry it open. Be careful not to use too much force, as the plastic clips can break easily. Inside, you'll find a CR2032 coin cell battery; use a small wooden stick to pop it out and replace it with a new one. When putting it back together, make sure the clips on the top and bottom covers align properly, and you should hear a click when they snap into place. Last time I bought a battery at the supermarket, it only cost me 5 yuan, saving over 200 yuan compared to going to the 4S shop. After replacing the battery, remember to press and hold the key to test if the lock/unlock functions work properly.