How to Change Key Battery Mercedes
The key battery in your Mercedes-Benz is responsible for powering the keyless entry system and remote start function. Over time, the battery will eventually die and need to be replaced. Replacing the battery is a simple process that can be done in a few minutes.
Here are the steps on how to change key battery Mercedes:
- Locate the small screw on the back of the key fob.
- Use a small screwdriver to remove the screw.
- Gently pry open the key fob.
- Locate the battery and remove it.
- Insert the new battery into the key fob.
- Snap the key fob back together.
- Replace the screw.
Tips:
- Use a new battery of the same type as the old battery.
- Do not overtighten the screw when replacing it.
- If you have trouble opening the key fob, you can use a thin object, such as a butter knife, to pry it open.
Conclusion:
Replacing the battery in your Mercedes-Benz key fob is a simple process that can be done in a few minutes. By following these steps, you can keep your key fob working properly and avoid the hassle of having to replace the entire key.
Identifying the Key Battery
When your Mercedes key stops working or shows signs of a weak battery, it’s time to replace it. Here’s a detailed guide on how to identify the key battery:
1. Locate the Key’s Battery Compartment:
The battery compartment is typically concealed within the key fob. Here are the common locations and steps to access it:
| Key Type | Battery Compartment Location | Access Instructions |
|---|---|---|
| Smart Key (Transponder Key) | Inside the key fob, accessible by pressing the silver button on the top or side | Press the button to release the key blade and reveal the battery compartment |
| Valet Key (Emergency Key) | No battery compartment | The valet key does not require a battery |
2. Inspect the Battery:
Once you have located the battery compartment, remove the battery and examine it carefully. Look for any signs of corrosion or leakage, which may indicate a battery failure.
3. Determine the Battery Size:
Mercedes keys typically use CR2025 or CR2032 button batteries. The battery size is usually printed on the battery itself. Note the size and ensure you purchase the correct replacement battery.
Preparing the Key
To prepare your Mercedes key for battery replacement, follow these steps:
- Locate the small keyhole on the side of the key.
- Insert the key of your car into the keyhole and gently pry the key fob apart.
- Be careful not to damage the key or the key fob during the separation process.
Accessing the Battery
Once the key fob is open, you’ll need to access the battery. Here’s how to do it:
- Use a small screwdriver or a pointed object to gently pry open the battery compartment.
- Locate the battery, which is usually a small coin-shaped CR2025 battery.
- Carefully remove the old battery by gently pushing it up from the compartment.
Installing the New Battery
To install the new battery, follow these steps:
- Make sure the positive (+) side of the new battery is facing up.
- Gently press the new battery into the compartment, ensuring it’s securely in place.
- Close the battery compartment by aligning the edges and pressing until it snaps shut.
| Battery Type | Mercedes Models |
|---|---|
| CR2025 | E-Class, S-Class, C-Class, GLC, GLE |
| CR2032 | G-Class, GLS |
Opening the Key Battery Compartment
1. Locate the Battery Compartment Release Button
Depending on your Mercedes model, the battery compartment release button may be located on the side or bottom of the key. It’s typically marked with a small symbol, such as a battery or a keyhole.
2. Press the Button and Slide Out the Compartment
Once you have located the battery compartment release button, press it and simultaneously slide the compartment outward. It may be necessary to apply gentle pressure to release the compartment fully.
3. Replace the Battery
Remove the old battery from the compartment, paying attention to the polarity of the contacts. Insert the new battery into the compartment, ensuring that the positive (+) and negative (-) contacts align correctly. Make sure the battery is securely seated and the compartment is closed before use.
| Battery Type | Mercedes Models |
|---|---|
| CR2025 | A-Class, C-Class, E-Class, S-Class, CLA-Class, GLA-Class, GLC-Class, GLE-Class, GLS-Class |
| CR2032 | G-Class, V-Class |
Removing the Old Battery
1. Locate the Key Battery: Identify the small battery compartment located on the side or back of the key fob. It may be marked with a small battery symbol.
2. Remove the Key Blade: On some key fobs, you will need to remove the key blade before accessing the battery. Press the release button or slide the blade outward to detach it.
3. Open the Battery Compartment: Use a small screwdriver or key to gently pry open the battery compartment cover. Be careful not to damage the surrounding plastic.
4. Extract the Old Battery: Once the compartment is open, use a pair of tweezers or a non-metallic tool to carefully lift out the old battery. Note its position and orientation for proper replacement.
| Battery Type | Estimated Battery Life |
|---|---|
| CR2025 | 2-5 years |
| CR2032 | 3-6 years |
5. Inspect the Battery Contacts: Before inserting the new battery, inspect the battery contacts in the compartment for any corrosion or debris. Clean them with a cotton swab dipped in rubbing alcohol if necessary.
Inserting the New Battery
Now that you have the necessary materials and have removed the old battery, it’s time to insert the new one.
1. Open the battery case cover by sliding it open with your thumb or a small screwdriver.
2. Locate the positive (+) and negative (-) terminals inside the battery case.
3. Insert the new battery into the case, ensuring the positive terminal of the battery aligns with the positive terminal of the case and the negative terminal aligns with the negative terminal.
4. Secure the battery by pressing it firmly into place until it clicks.
5. Carefully close the battery case cover, ensuring it is securely fastened.
Here is a step-by-step guide with additional details on step 5:
- Inspect the battery case cover for any visible damage or cracks.
- Align the cover with the base of the key fob, ensuring the edges match up correctly.
- Apply gentle pressure to the edges of the cover, gradually pressing it down until it snaps into place securely.
- Run your fingers around the perimeter of the cover to ensure it is fully seated and there are no gaps.
- Double-check the fit by gently tugging on the cover to make sure it is secure and not loose.
Testing the Key
Before diving into the replacement process, verify if the key battery is indeed the culprit. Here’s a simple test to confirm:
- Hold the key in one hand and press any button with the other.
- Observe if there’s a visible LED light flashing. If so, the battery is likely still functional.
- If there’s no light, repeat the process with all the key buttons.
- If none of the buttons trigger the LED light, proceed with replacing the battery.
Note that this test is only an initial indication, and a faulty battery may still be the cause even if the LED light flashes. If you continue experiencing issues after the battery replacement, consider having your key diagnosed by a mechanic.
Closing the Key Battery Compartment
To close the key battery compartment, simply follow these steps in reverse order:
- Align the battery cover with the key body.
- Gently slide the cover into place, ensuring that it fits snugly.
- Press down firmly on the cover to secure it in place.
It is important to make sure that the battery cover is properly closed to prevent the battery from falling out or becoming loose.
Additional Tips:
- When closing the key battery compartment, do not apply excessive force, as this could damage the cover or the key.
- If you are having difficulty closing the cover, check to make sure that the battery is properly inserted and that there are no obstructions in the compartment.
Once the key battery compartment is closed, the key should be ready for use.
Table: Troubleshooting Common Problems
| Problem | Solution |
|---|---|
| Key battery compartment cover will not close | Ensure that the battery is properly inserted and that there are no obstructions in the compartment. |
| Key battery compartment cover is loose | Press down firmly on the cover to secure it in place. |
| Key battery compartment cover is damaged | Replace the key battery compartment cover. |
Finding the Right Battery
Refer to your owner’s manual to determine the correct battery type for your Mercedes key. Common battery types include CR2025 or CR2032.
Removing the Old Battery
Locate the small slot on the back of the key fob. Use a tiny screwdriver or a paperclip to gently pry open the fob.
Inserting the New Battery
Place the new battery into the fob, ensuring that the positive (+) side faces up. Press down on the battery until it clicks into place.
Closing the Fob
Align the two halves of the fob and press them together firmly until they snap shut.
Programming the Key (Optional)
Programming the Key (Optional)
If your Mercedes key has advanced features like keyless entry, you may need to reprogram it after replacing the battery.
Method 1: Using the Vehicle Keyhole
Insert the key into the vehicle’s door lock and turn it to the unlock position four times within 10 seconds. Remove the key and press any button on the key fob.
Method 2: Using the Emergency Key
Remove the emergency key from the back of the key fob. Insert the emergency key into the driver’s side door lock and hold it in the unlock position. Simultaneously press the unlock button on the key fob until the vehicle unlocks.
Method 3: Using a Mercedes Dealer
If you are unable to program the key yourself, you can visit a Mercedes dealership to have it done professionally.
Troubleshooting Key Battery Replacement
If you’re unable to replace the key battery successfully, here are some troubleshooting tips:
1. Check the Battery Type: Make sure you have the correct battery type for your Mercedes key.
2. Verify Battery Polarity: Ensure the battery is inserted with the positive terminal facing the correct direction.
3. Wiggle the Battery: Sometimes, the battery may not make proper contact. Try wiggling it gently to improve connectivity.
4. Clean Battery Contacts: Corrosion or debris on the battery contacts can prevent it from functioning. Clean the contacts with a cotton swab and rubbing alcohol.
5. Check Keypad Buttons: If the buttons on the key fob are not working, try pressing them multiple times to dislodge any debris.
6. Test Spare Key: If you have a spare key, try replacing the battery in that one to see if it works. This will help isolate the issue to the key or the battery.
9. Inspect Key Fob for Damage
Thoroughly examine the key fob for any physical damage, such as cracks, dents, or water damage. The following are specific areas to consider:
a. Battery Compartment: Check for corrosion, loose connections, or broken contacts within the battery compartment.
b. Circuit Board: Look for any visible scratches, burns, or discoloration on the circuit board.
c. Antenna: Inspect the antenna for breaks or kinks. The antenna is typically located along the edge of the fob.
d. Buttons: Examine the buttons for any signs of wear, tear, or stuck debris.
If significant damage is present, it may be necessary to replace the key fob or seek professional repair.
How to Change Key Battery Mercedes
Replacing the battery in your Mercedes key is a simple process that can be done in just a few minutes. Here’s a step-by-step guide:
1. Gather your materials
You will need a new battery for your Mercedes key. The type of battery you need will depend on the model of your key. You can refer to your owner’s manual to find out which type of battery is required.
2. Remove the key blade
Locate the small button on the back of the key and press it. This will release the key blade. Pull the key blade out of the key.
3. Open the key fob
Locate the small notch on the side of the key fob. Insert a small screwdriver or other tool into the notch and gently pry the key fob open.
4. Remove the old battery
Locate the old battery inside the key fob. Use a small screwdriver or other tool to gently pry the battery out of its compartment.
5. Insert the new battery
Insert the new battery into the battery compartment. Make sure that the positive and negative terminals of the battery are facing the correct direction.
6. Close the key fob
Close the key fob by snapping it shut. Make sure that the key fob is securely closed.
7. Test the key
Press the buttons on the key to test it. If the key is working properly, you will see the LED lights on the key fob light up.
8. Insert the key blade
Insert the key blade back into the key fob. Make sure that the key blade is fully inserted.
9. Tips for Extending Key Battery Life
Here are a few tips to help extend the life of your Mercedes key battery:
- Avoid leaving your key in direct sunlight or extreme temperatures.
- Do not press the buttons on your key unnecessarily.
- If you are not using your Mercedes for an extended period of time, remove the battery from the key fob.
- Have your Mercedes key battery replaced by a qualified technician every 2-3 years.
10.
| Symptom | Possible Cause(s) |
|---|---|
| Key fob does not work |
|
| Key fob range is reduced |
|
| Key fob buttons are not working properly |
|
How To Change Key Battery Mercedes
Follow these steps to change the key battery in your Mercedes:
- Locate the key battery.
- Use a small screwdriver or coin to pry open the cover.
- Remove the old battery and insert the new battery. Make sure the positive (+) and negative (-) terminals are facing the correct way.
- Replace the cover and test the key to make sure it is working properly.
People Also Ask
How often should I change my Mercedes key battery?
You should change your Mercedes key battery every 2-3 years, or more often if you use your key frequently.
What type of battery do I need for my Mercedes key?
You need a CR2025 3-volt battery for your Mercedes key.
Can I change the key battery in my Mercedes myself?
Yes, you can change the key battery in your Mercedes yourself. It is a simple process that takes only a few minutes.
