Posted by James Boyle

Is your BMW remote key acting up due to a flat battery? Don't worry; replacing it is a quick and straightforward process. In this step-by-step guide, we'll walk you through the simple DIY steps to replace the flat battery in your BMW key for models including 3/5/7 Series, X3, X5, Z4, E38, E39, M5, and M3. The battery you'll need is a CR 2025, available for purchase here.

 Step 1: Open the Car Key Shell

To begin the battery replacement process, use a small screwdriver to open the car key shell. Locate the seam along the edge of the key fob and gently insert the screwdriver to release the clips holding the two halves together.

Step 2: Pop Out the Existing Flat Battery

Once the car key shell is open, you'll find the existing flat battery. Carefully pop it out using the screwdriver or a similar tool. Be mindful not to damage the key or surrounding components during this step.

Step 3: Insert the New Battery

Now, take your new CR 2025 battery, ensuring the positive (+) side faces up. Insert the new battery into the designated slot in the car key shell. Press it down gently to secure it in place.

Step 4: Close the Car Key Shell

With the new battery in place, it's time to close the car key shell. Align the two halves, making sure they fit together correctly. Apply gentle pressure to snap the clips back into place. Use the screwdriver to secure any screws that may be present, ensuring the car key shell is tightly closed.

If you prefer a hassle-free solution, you can purchase a complete BMW 3-button key remote here. Additionally, replacement cases/shells are available here for those looking to refresh the appearance of their key fob.

With these simple steps, you can easily replace the battery in your BMW remote key, ensuring optimal performance and reliability.