How to Change the Battery in Your Mercedes-Benz Key Fob

Is the battery of your Mercedes-Benz key fob on its last legs? In the guide below, we’ll go over the telltale signs of a dying key fob battery, how to open your Chrome Key or Smart Key, how to start a Mercedes-Benz with a key when your key fob battery is dead, and how to replace the battery.

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When To Replace Your Mercedes-Benz Key Fob Battery

There are several warning signs that indicate it’s about time to change the battery in your Mercedes-Benz key fob:

• You may notice your vehicle is gradually becoming more difficult to start. If it takes several minutes or multiple attempts, it can indicate a weak key fob battery.
• If you lose the ability to lock and unlock your doors or set off the panic alarm, your battery might be on its way out.
• If you notice a warning sign on your dashboard that indicates an issue with the charging system, it can mean that you are losing battery power in your key fob.

If you experience any of these warning signs, take the proactive step to change the battery in your Mercedes-Benz key fob to prevent issues when on the road in West Bloomfield.

Which Mercedes-Benz Key Fob Battery Do I Need?

When it comes time to change the battery in your Mercedes-Benz key fob, the first thing you’ll need to do is determine whether you have a Chrome Key or a Smart Key. This will impact how the batteries are changed because a Smart Key needs two CR 2025 batteries, while the newer Chrome Key only needs one.

How to Open Your Mercedes-Benz Car Key Fob to Replace the Battery

The process for how to replace a key battery Mercedes-Benz differs for Chrome Keys and Smart Keys—but once you get your key fob open and access the battery, changing it out is simple! Here’s how to open a Mercedes-Benz key fob for the Chrome Key or Smart Key:

To open a Mercedes-Benz Chrome Key and replace the battery:

• Look for a silver square-shaped tab on the bottom of the key. Pull it until it releases the spare key.
• You should now see a small gap in the fob casing. Push the spare key into the narrow and flat end of the fob and open the key cover.
• Remove and replace the old battery, ensuring that it is facing the right way.

To open a Mercedes-Benz Smart Key and replace the battery:

• Pull the latch end of the fob to release the key.
• In its place, you should see a slot at the end of the fob casing.
• Insert the key here to open the battery compartment.
• Remove and replace the old battery after making sure it is facing the right way.

How To Start a Mercedes-Benz With a Dead Key Fob

What if your key fob battery dies while you’re out on the road in Troy? You may know how to open a Mercedes-Benz key fob and how to replace the key battery for your Mercedes-Benz, but neither is much use when you don’t have a replacement battery on hand. No worries — all you need to know is how to start a Mercedes-Benz with a key, manually. These steps should work for any model with a Start/Stop button:

1. First, remove the metal blade key that is stored inside your key fob and use it to manually unlock the vehicle.
2. Pull the Engine Start/Stop button from the ignition lock. It should release easily with a gentle tug.
3. Put your car in Park and insert your SmartKey® into the ignition. Press the brake pedal.
4. Turn the key in the ignition, start the engine, and release the key as soon as the engine turns over.
5. Set the Engine Start/Stop button aside someplace safe. You’ll need to reinsert it in the ignition lock when you change the battery in your Mercedes-Benz key fob.
6. In the meantime, you can simply use your metal key to lock and unlock your Mercedes-Benz manually.

Experience Affordable Mercedes-Benz Service Cost at Mercedes-Benz of Bloomfield Hills

Need a Mercedes-Benz battery replacement key, or have questions about other car-care issues like jump-starting a dead battery? Our Bloomfield Hills service center can provide expert car care advice or perform the services you need at a reasonable price. Feel free to contact us with any questions, and be sure to check out our service specials before booking your appointment!

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