Maintaining a functional BMW key fob is crucial for the seamless operation of your vehicle. However, when the battery starts to deplete, you may encounter issues unlocking or starting your car. Replacing the battery in a BMW key fob is a relatively simple task that can be accomplished in just a few minutes. Follow our step-by-step guide to learn how to replace the battery in your BMW key fob, ensuring uninterrupted convenience and peace of mind.
The first step is to gather the necessary tools and materials. You will need a new CR2032 battery, a small flathead screwdriver or a key fob battery replacement tool. Once you have these items, you can begin the replacement process. Locate the small release button on the side of the key fob and press it while simultaneously pulling the key blade out. Next, use a small flathead screwdriver to gently pry open the back cover of the key fob, being careful not to damage the delicate components inside.
Once the back cover is removed, you will see the battery. Remove the old battery and replace it with the new CR2032 battery, ensuring correct polarity. The positive side of the battery should face up. Once the new battery is in place, gently snap the back cover back onto the key fob, ensuring it is securely closed. Finally, reinsert the key blade and test the key fob to verify if it’s working correctly. If the key fob functions properly, your battery replacement was successful, and you can continue using your BMW as usual.
Identifying Your BMW Key Fob Model
Determining the specific model of your BMW key fob is crucial before attempting to replace the battery. BMW has utilized various key fob designs throughout its history, and each model may require different procedures for battery replacement. To accurately identify your key fob model, follow these steps:
Physical Examination:
Carefully inspect the physical appearance of your key fob. Older BMW key fobs typically have a rectangular shape with buttons arranged in a vertical or horizontal row. Newer models may adopt different shapes, such as the rounded design found in recent BMW vehicles. Pay attention to the number of buttons, their placement, and any distinctive features on the fob’s surface.
Logo and Badge Verification:
Examine the key fob for the BMW logo or badge. This can usually be found on the front or back of the device. The logo may indicate the approximate era of the key fob, as BMW has updated its branding over the years. Additionally, some key fob models may feature specific model designations, such as “CAS” or “EWS,” etched or printed on the device.
Remote Control Functions:
Observe the functionality of your key fob. Does it only unlock and lock the vehicle remotely? Or does it also feature additional functions such as trunk release, panic alarm, or even keyless entry? Identifying these features can help narrow down the possible key fob models.
Table of BMW Key Fob Models:
| Key Fob Model | Physical Characteristics | Remote Control Functions |
|---|---|---|
| EWS | Rectangular with 2 or 3 buttons | Unlock/Lock only |
| CAS | Rounded with 4 or more buttons | Unlock/Lock, Trunk Release, Panic Alarm |
| Comfort Access | Keyless entry, Start/Stop button | Unlock/Lock, Trunk Release, Keyless Entry, Start/Stop Engine |
Gathering Necessary Tools and Materials
Before embarking on the task of replacing the battery in your BMW key fob, it is crucial to gather the necessary tools and materials. Here’s a comprehensive list to ensure a smooth and trouble-free process:
Tools
- Small flat-head screwdriver
- Phillips-head screwdriver (optional)
Materials
- New CR2032 or CR2025 battery
- Clean cloth or microfiber towel
Safety Precautions
Handle the key fob with care and avoid using excessive force. If any difficulties are encountered during the process, it is recommended to consult a qualified mechanic or locksmith for assistance.
Opening the Key Fob Casing
To access the battery, you’ll first need to open the key fob casing. This process may vary slightly depending on the specific model of your BMW key fob, but generally, it involves the following steps:
1. Locate the Key Fob Release Button
On most BMW key fobs, there is a small button located on the side or bottom of the casing. This button is designed to release the key blade, allowing you to remove it from the fob. To open the casing, you’ll need to locate and press this release button.
2. Remove the Key Blade
Once you’ve pressed the release button, the key blade will pop out slightly. Carefully remove the key blade from the casing by pulling it straight out.
3. Pry Open the Casing
With the key blade removed, you should now be able to see a small seam or gap in the key fob casing. Using a thin tool, such as a small screwdriver or a flat-head key, gently pry open the casing along the seam. Be careful not to damage the casing or its components.
| Tool Options |
|---|
| Small screwdriver |
| Flat-head key |
Once you’ve successfully opened the key fob casing, you’ll have access to the battery and other internal components.
Closing the Key Fob Casing
6. Closing the Key Fob Casing
a) Align the two halves of the key fob casing, making sure the buttons and edges are properly aligned.
b) Gently press down on the edges of the casing to snap them back together. Start from one end and work your way around the perimeter.
c) Ensure that the casing is fully closed and there are no gaps or misalignments.
d) Double-check that all buttons are functioning properly and the key fob is operating as intended.
Additional Tips:
1. Avoid pressing too hard when closing the casing, as this can damage the delicate parts inside.
2. If you encounter any resistance while closing the casing, inspect the alignment and try again.
3. Clean the casing with a soft cloth before closing it to remove any debris or dirt that could interfere with the fit.
4. If the key fob is not functioning properly after closing, inspect the battery contacts and ensure they are properly connected.
5. For safety, handle the key fob with care and avoid dropping or exposing it to extreme temperatures or moisture.
How to Replace Battery In BMW Key Fob
Replacing the battery in a BMW key fob is a simple process that can be completed in a few minutes. Here are the steps on how to do it:
- Remove the key blade from the fob by pressing the small button on the side of the fob and pulling the key blade out.
- Use a small screwdriver or other thin object to pry open the back of the fob. Be careful not to damage the fob or the battery.
- Remove the old battery from the fob and dispose of it properly.
- Insert the new battery into the fob, making sure that the positive and negative terminals are aligned correctly.
- Close the back of the fob and snap it into place.
- Reinsert the key blade into the fob.
Your BMW key fob should now be working properly.
