DIY Mercedes Key Fob Battery Replacement

Completing factory-recommended maintenance is a critical part of car ownership. Not only does it help to ensure your vehicle is safe to drive, but preventative care also deters more significant issues from occurring in the future. Yet, only some repairs require the skill of a certified mechanic.

With a bit of knowledge and patience, there are tasks even a novice driver can take on to diagnose and fix a problem. Take, for example, a Mercedes key battery replacement. Do you really need the help of a specialist shop or dealership to swap the old battery for a new one, or can you do it yourself? Before wasting time and money employing the services of someone else, consider the following tips to tackle this small task solo.

1. Know the Signs of a Dying Fob Battery

Not every car issue is noticeable. But figuring out if you need a Mercedes key battery replacement is relatively simple. Watch out for the following signs suggesting your fob’s battery is dying:

• You try to start your car’s engine with the key fob several times before it finally works.
• Your fob stops letting you lock or unlock your car doors or turn off the panic alarm.
• A warning sign on your dash illuminates, alerting you to replace your fob battery. (Some, not all, models have this feature.)

2. Identify Your Benz’s Fob Type

Your car’s owner’s manual is an excellent resource for finding information involving your vehicle’s parts and their functions. In fact, this should be the first place you look to as soon as you realize your Mercedes key fob needs a new battery. Why? You will want to determine your key fob type first to know which battery to buy and the steps to take to replace it. Older Mercedes models use “SmartKey” fobs encased in plastic and have circular panic buttons. In contrast, newer models use one of two types of “Chrome Key” fobs encased in metal and have triangular panic buttons.

3. Buy the Correct Key Battery Replacements

Some of the most highly rated batteries are from popular brands like Energizer Lithium or Duracell, which you can find locally at a Walmart, Home Depot, or Lowes store. But before making your purchase, check customer ratings, life span length, and battery function—especially for things like extreme temperatures—to ensure you get the best product for your needs and budget. Also, remember that the SmartKey fobs and older Chrome Keys require two CR2025 batteries, while the newer Chrome Key only takes one. If you aren’t entirely sure, contact your dealership for additional information. You might find out they’ll replace the batteries for you for free. (Some do!)

4. Follow the Steps to Replace the Battery

The process you take to replace your Mercedes key fob battery will ultimately depend on your vehicle’s age and fob type. But once you have that information, you can quickly fix the issue by replacing old batteries with new ones.

If your Mercedes-Benz uses an older SmartKey device:

• First, locate the small release tab on the back end of the key holder and slide it over, allowing the key to pop out.
• Next, turn the fob over and insert the key into the opening on the other side with a slight push, which will cause the battery cover to pop off.
• Then, replace the old battery with one or two CR2025 three-volt batteries depending on your fob, with the positive side/engraved side up.
• Reattach the back cover and reinsert the key.
• Finally, press and hold any button to confirm the fob works by watching for the LED light to illuminate.

If your Mercedes-Benz uses the newer Chrome SmartKey:

• First, push the release button on the back of the fob and pull on the keyring to remove the key blade.
• Next, press the release button again and use the key to get under the back cover. Pull the cover away by sliding it off the fob.
• Then, locate the little door on the side of the fob, remove it, and replace the old battery with a new CR2032 three-volt battery, with the positive side facing down.
• Reinsert the door with the new battery into the fob, slide the cover back on, and push it forward until the cover snaps into place.
• Finally, press and hold the button to confirm the red LED button illuminates to show the fob is working.

Secure Extended Coverage Protection

With the help of a vehicle protection plan that includes extra benefits like Mercedes Benz key fob replacements or lockout services, you don’t have to worry about losing your key fob or discovering that it’s broken. Instead, you can count on your policy to cover the cost of a new fob or help you get back on the road when stranded or locked out.

So where can you get a plan that does this? At Extended Auto Warranty, we aim to help you find the most beneficial auto breakdown plans by presenting unbiased reviews of America’s top warranty providers on our website. Our extensive research and first-hand experience offer a deep dive into each extended warranty service, so you can find the best and most affordable coverage.