The BMW key is a sophisticated device that allows you to lock, unlock, and start your car. It also has a number of other features, such as remote trunk release and window control. Like all batteries, the battery in your BMW key will eventually need to be replaced. Replacing the battery is a simple process that can be done in just a few minutes. In this article, we will show you how to change the battery in your BMW key.
The first step is to identify the type of battery that your BMW key uses. There are two types of batteries that are commonly used in BMW keys: CR2025 and CR2032. You can find the type of battery that your key uses by looking at the back of the key. Once you know the type of battery that you need, you can purchase a new battery at your local hardware store or online.
Next, you will need to remove the old battery from your key. To do this, you will need to use a small screwdriver to pry open the back of the key. Be careful not to damage the key when you are doing this.
Once you have removed the old battery, you can insert the new battery into the key. Make sure that the positive (+) side of the battery is facing up. Once you have inserted the new battery, you can close the back of the key and test it to make sure that it is working properly.
Battery Replacement Process
Before you begin the battery replacement process, it is important to gather the necessary tools and materials. You will need a new CR2032 battery and a small Phillips head screwdriver. Once you have gathered your materials, follow these steps to replace the battery in your BMW key:
- Locate the battery compartment. The battery compartment is typically located on the back of the key. On some models, the compartment may be hidden behind a small cover. To remove the cover, use a small Phillips head screwdriver to unscrew the screws that hold the cover in place.
- Remove the old battery. Once you have located the battery compartment, use your fingernail or a small tool to remove the old battery. Be careful not to damage the battery or the key.
- Insert the new battery. Take the new CR2032 battery and insert it into the battery compartment. Make sure that the positive (+) side of the battery is facing up.
- Replace the battery compartment cover. If you removed the battery compartment cover, replace it by screwing in the screws that hold it in place.
- Test the key. Once you have replaced the battery, test the key to make sure it is working properly. Press the buttons on the key to see if they are functioning.
If the key is not working properly, you may need to replace the battery again. If you are still having problems, you may need to take the key to a BMW dealership for further assistance.
Material Description CR2032 battery A small, coin-shaped battery that is used to power many electronic devices, including BMW keys. Small Phillips head screwdriver A small screwdriver that is used to remove the screws that hold the battery compartment cover in place. Identifying the Correct Battery
Identifying the correct replacement battery for your BMW key is crucial to ensure proper functionality and longevity. To determine the correct battery type, follow these steps:
1. Check the Key Manual:
If you still have the user manual for your BMW, it will likely specify the battery type required. Refer to the manual for the exact battery model or part number.
2. Remove and Inspect the Existing Battery:
Carefully remove the key cover by pressing the release button or prying it open with a small flathead screwdriver. Once the cover is removed, you can access the battery. Note the shape, size, and any markings or numbers printed on the battery. This information will help you identify the correct replacement battery.
BMW Key Series Battery Type E series (E36, E39, E46, E60) CR2032 F series (F10, F20, F30, F36) CR2450 G series (G20, G30, G31, G42) CR2025 Locating the Key’s Battery Compartment
Identifying the Type of Key
BMW keys come in various types, each with a distinct battery compartment location. Determine the type of key you have before proceeding:
- Flip Key: A traditional key that flips open to reveal the key blade.
- Smart Key (Non-Display): A keyless entry remote without a display screen.
- Smart Key (Display): A keyless entry remote with an LCD display screen.
- Comfort Access Key: A keyless entry remote that allows for locking and unlocking the vehicle without touching the key.
Finding the Battery Compartment
Once you have identified the key type, follow these steps to locate the battery compartment:
- Flip Key: Insert the key blade into the vehicle ignition and turn it slightly to release the key from the casing. The battery compartment is typically located on the back of the key.
- Smart Key (Non-Display): Slide open the back cover of the key to reveal the battery compartment.
- Smart Key (Display): Press the key release button on the back of the key to detach the key blade. The battery compartment is located on the bottom of the key blade.
- Comfort Access Key: Remove the small, silver key fob from the Comfort Access key and flip open the back cover of the fob. The battery compartment is located inside the fob.
Safely Removing the Old Battery
Before you begin, gather the necessary tools: a small flathead screwdriver or SIM card removal tool, a new CR2032 battery, and a clean work surface.
Step 1: Locate the Battery Compartment
Turn the key over to reveal the battery compartment, typically located on the back of the key.
Step 2: Unlock the Compartment
Using the flathead screwdriver or SIM card tool, gently pry open the battery compartment cover. Be careful not to damage the key.
Step 3: Remove the Old Battery
Locate the old battery and gently lift it out of the compartment using a flathead screwdriver or your finger.
Step 4: Inspect the Battery Slot
Thoroughly inspect the battery slot for any corrosion or damage. Use a clean cotton swab or compressed air to clean any debris.
Additional Considerations:
- Never touch the terminals of the battery with your bare hands, as oils from your skin can damage the battery.
- Avoid using sharp objects or excessive force when removing the battery, as this can damage the key.
- Do not store the key in extreme temperatures.
Inserting the New Battery
Once you have the new battery, it’s time to insert it into the key fob. To do this:
- Locate the battery compartment. It is usually located on the back of the key fob, covered by a small panel.
- Remove the panel. Gently pry it off using a small screwdriver or a flathead screwdriver.
- Take out the old battery. Note the orientation of the old battery and remove it from the compartment.
- Insert the new battery. Make sure to insert the new battery in the correct orientation, as indicated by the "+" and "-" symbols inside the compartment.
- Replace the panel. Line up the panel with the key fob and gently press it back into place until it snaps shut.
Tips for Inserting the New Battery
- Handle the battery with care to avoid damaging it.
- Make sure the battery is installed securely to prevent it from rattling or falling out.
- If you have any difficulty inserting the battery, refer to the owner’s manual for specific instructions.
- Replace the battery as soon as possible after it runs out to avoid any inconvenience.
Correct Battery Orientation
To ensure proper functionality of your BMW key, it’s crucial to insert the battery in the correct orientation. Follow these steps to align the battery accurately:
1. Locate the Battery Compartment
Open the BMW key case using the provided keyhole or switch on the side. Locate the battery compartment inside the housing.
2. Remove the Old Battery
Gently pry out the old battery from the compartment using a small tool or your fingers. Dispose of the old battery responsibly.
3. Check the Battery’s Orientation
Examine the battery terminals and the corresponding contacts in the battery compartment. The positive (+) terminal is typically marked with a small notch and should align with the raised, positive contact in the compartment.
4. Align the Battery
Align the positive terminal of the new battery with the positive contact in the compartment. Carefully insert the battery into the compartment, making sure it fits snugly.
5. Double-Check
Once the battery is inserted, re-check the orientation to ensure the positive and negative terminals are aligned correctly.
6. Advanced Orientation Guide
For specific BMW key models, the battery orientation may vary slightly. Refer to the following table for model-specific battery orientation:
BMW Key Model Battery Orientation CAS-1 Negative terminal faces the top of the key CAS-2 Positive terminal faces the top of the key CAS-3 Negative terminal faces the bottom of the key CAS-4 Positive terminal faces the bottom of the key Closing the Battery Compartment
1. Align the battery compartment cover with its corresponding slot on the key fob.
2. Slide the cover back into place until it clicks securely.
3. Flip the key fob upright to return it to its normal position.
4. The key should now be fully functional with a new battery.
Here are some additional tips for closing the battery compartment:
- Make sure the battery is properly aligned before closing the cover.
- Apply a gentle but firm pressure to the cover when sliding it back into place.
- Check that the cover is completely closed and flush with the key fob.
Testing Key Function
To ensure that the issue is with the battery and not the key itself, test the key’s functionality by trying the following:
1. Unlock/Lock the Car
Press the unlock and lock buttons on the key to see if the car responds. If the car locks or unlocks, the key is likely functional, and the issue may be with the battery.
2. Start the Car
With the key in the ignition, attempt to start the car. If the car starts successfully, the key is functional, and the battery may need replacement.
3. Change Frequency
Some BMW keys can change frequency to open different cars. Try switching the frequency and see if that solves the issue.
4. Open the Trunk
Use the trunk release button on the key to open the trunk. If the trunk opens, the key is likely functional, and the issue may be with the battery.
5. Remote Windows
If your BMW has remote windows, try using the key to open or close the windows. If the windows respond, the key is likely functional, and the issue may be with the battery.
6. Comfort Access
If your BMW has comfort access, try unlocking or starting the car without the key in hand. If the car responds, the key is likely functional, and the issue may be with the battery.
7. Check Indicator Light
Some BMW keys have an LED indicator light that flashes when the battery is low. If the light is flashing, the battery needs to be replaced.
8. Digital Key (BMW App)
If your BMW has the digital key feature, try using the BMW app on your phone to unlock or start the car. If the app works, the key itself may be faulty or have a low battery.
Method Battery Voltage Mechanical Key N/A Remote Key 3V Comfort Access Key 3V Battery Maintenance Tips
To ensure the longevity of your BMW key battery, consider the following maintenance tips:
1. Avoid extreme temperatures: Extreme heat or cold can shorten battery life.
2. Use correctly sized battery: Ensure the battery matches the specifications required by your key.
3. Clean battery contacts: Regularly clean the battery contacts to prevent corrosion.
4. Store key properly: Store your key in a dry, cool location when not in use.
5. Avoid dropping key: Dropping or damaging the key can compromise the battery’s integrity.
6. Replace battery regularly: Replace the battery as recommended by the manufacturer or when the key starts showing signs of reduced performance.
7. Test battery periodically: Use a multimeter or battery tester to check the battery’s voltage and ensure it is at optimal levels.
8. Use high-quality batteries: Opt for reputable battery brands known for their reliable performance.
9. Monitor key usage: Be mindful of how often you use your key and consider replacing the battery proactively if it is used frequently.
Battery Type Voltage Lifespan CR2025 3V 2-3 years CR2032 3V 3-5 years CR2450 3V 4-6 years Seeking Professional Assistance
If you are encountering difficulties replacing the battery in your BMW key, it is advisable to seek professional assistance from a qualified automotive technician or locksmith. They possess the necessary expertise, tools, and experience to handle such tasks efficiently and accurately. Here are some benefits of seeking professional assistance:
- Guaranteed Accuracy: Trained professionals ensure precise battery replacement, minimizing the risk of damage to your key or vehicle’s ignition system.
- Time Conservation: Experts can swiftly diagnose and resolve the issue, saving you valuable time and reducing frustration.
- Expertise in Key Programming: If your BMW key requires programming after battery replacement, professionals have the necessary equipment and skills to complete the process flawlessly.
- Use of Genuine Parts: Reputable technicians employ authentic BMW parts, ensuring compatibility and extended battery life.
- Peace of Mind: Entrusting professionals with the task provides peace of mind, knowing your key and vehicle are in capable hands.
- A new CR2032 battery
- A small flathead screwdriver
- The key fob does not work.
- The key fob works intermittently.
- The key fob has a weak signal.
How To Change Battery In BMW Key
To change the battery in your BMW key, you will need the following items:
Once you have these items, follow these steps to change the battery:
1. Use the flathead screwdriver to pry open the key fob.
2. Locate the battery and remove it from the fob.
3. Insert the new battery into the fob, making sure that the positive (+) side of the battery is facing up.
4. Close the key fob and test it to make sure it is working properly.
People Also Ask About How To Change Battery In BMW Key
How often should I change the battery in my BMW key?
The battery in your BMW key should be changed about every two years.
What are the signs of a dead battery in my BMW key?
The signs of a dead battery in your BMW key include:
Can I change the battery in my BMW key myself?
Yes, you can change the battery in your BMW key yourself. The process is simple and only takes a few minutes.
