Experiencing a flickering response from your Mercedes Benz key fob? Or maybe it’s stopped working altogether? Before you panic and schedule a costly dealership visit, there’s a good chance a simple battery replacement is all you need. This guide will walk you through the process of how to replace a Mercedes Benz key fob battery quickly and easily, saving you both time and money.
Why is My Mercedes Key Fob Not Working?
A few telltale signs indicate it might be time to replace the battery in your Mercedes key fob:
- Decreased range: You find yourself standing closer to your car to lock or unlock it.
- Intermittent functionality: The key fob works sometimes but not others, or you have to press the buttons multiple times.
- Warning messages: Your dashboard displays a “Key Fob Battery Low” message.
If you’re experiencing any of these issues, a dead or dying battery is likely the culprit.
What Kind of Battery Does a Mercedes Key Fob Take?
Most Mercedes Benz key fobs use a small, flat CR2025 or CR2032 battery. These are readily available at most supermarkets, drugstores, and electronics retailers. You can usually find them in the same aisle as watch batteries.
Tools You’ll Need for Mercedes Key Fob Battery Replacement
The good news is you won’t need any special tools for this task. Most Mercedes key fobs are designed for easy battery replacement using just a few household items:
- Small flat-head screwdriver or a plastic pry tool (to avoid scratching the key fob)
- Replacement battery (CR2025 or CR2032, check your owner’s manual or the existing battery for the correct type)
How to Open a Mercedes Key Fob to Change the Battery
Mercedes designs its key fobs to be sleek and integrated, which might make it unclear how to access the battery compartment. Here’s a step-by-step guide to help you open it up:
- Locate the release button or notch: Examine your Mercedes key fob for a small button or notch. This is usually located on the back or side of the fob.
- Release the emergency key: Press the release button or use your fingernail to slide the emergency key blade out from the fob. This will often reveal the battery compartment.
- Separate the key fob halves: Gently pry open the key fob halves using your flat-head screwdriver or plastic pry tool. Be careful not to use excessive force, as this could damage the fob.
Replacing the Mercedes Benz Key Fob Battery
Once you have the key fob open, follow these steps to replace the battery:
- Identify the battery orientation: Note the positive (+) and negative (-) markings on the old battery and the battery compartment.
- Remove the old battery: Carefully remove the old battery from the compartment. You can use your fingernail or the flat end of your screwdriver to gently lift it out.
- Insert the new battery: Align the positive (+) and negative (-) markings on the new battery with the corresponding markings in the compartment. Gently press the battery into place.
- Reassemble the key fob: Align the two halves of the key fob and press them together until you hear a click, indicating they are securely closed.
- Reinsert the emergency key: Slide the emergency key blade back into its slot on the fob.
Mercedes Key Fob Battery Replacement Cost
Replacing your Mercedes key fob battery yourself is very affordable. A single CR2025 or CR2032 battery typically costs just a few dollars. This is significantly cheaper than having the battery replaced at a dealership, which can sometimes cost upwards of $50.
“Many people are surprised at how easy it is to replace their Mercedes key fob battery themselves,” says Tim Johnson, Senior Automotive Technician at Car Diag Tech. “It’s a simple DIY task that can save you a significant amount of money.”
Testing Your New Key Fob Battery
After replacing the battery, test the key fob to ensure it’s functioning properly. Try locking and unlocking your car doors, and start the engine to confirm the key fob is communicating correctly.
Frequently Asked Questions
Can I Program a Mercedes Key Fob Myself?
Programming a new Mercedes key fob can be a complex process that often requires specialized equipment and knowledge. Can I program a Mercedes key fob myself? Learn more about the process and what it entails.
How Much is a Key Fob Battery?
Key fob batteries are very affordable, generally costing between $3 and $7 depending on the brand and where you purchase it. To get a better understanding of pricing, check out our detailed guide on how much is a key fob battery.
How Do I Open a Mercedes Key Fob?
Opening a Mercedes key fob to access the battery compartment is designed to be simple. For a step-by-step guide with images, see our article on how do I open a Mercedes key fob.
What Should I Do If My Mercedes Key Fob Still Doesn’t Work?
If you’ve replaced the battery and your key fob is still not working, there may be a more significant issue, such as a faulty key fob or a problem with your car’s receiver. In such cases, it’s best to consult a qualified automotive locksmith or your Mercedes dealership for assistance.
Keep Your Mercedes Running Smoothly
Replacing your Mercedes Benz key fob battery is a quick and easy way to avoid frustrating lockouts and ensure your key fob remains in top working condition. By following these simple steps and keeping a spare battery on hand, you can tackle this DIY task with confidence and get back on the road in no time.
