If your Mercedes key fob starts sensing at shorter ranges or has difficulty locking doors, it’s likely you need a new key battery. Fortunately, it’s a simple fix you can do at home. With a few extra minutes, you’ll be clicking with full power and ready to roll.
What kind of battery goes in a Mercedes key fob?
Like most key fobs on the market, the Mercedes Chrome Key and SmartKey fobs use 3-volt lithium batteries. These are the small, flat silver batteries often referred to as “coin” batteries due to their appearance. Mercedes fobs use either one or two CR 2025 batteries.
Where Can I Find a Mercedes Key Fob Battery and How Much Will it Cost?
You’ll find CR 2025 3-volt lithium batteries almost anywhere that sells consumer-grade batteries such as AA, AAA and D. The CR 2025 usually comes in packs of 2, 4, 8, or 10 batteries. You can also buy them in bulk from online retailers for increased cost savings.
When purchasing CR 2025 batteries for your Mercedes key fob, expect to pay the highest prices from leading battery manufacturers. Packs of 2 and 4 range from about $4 to $8. For lower prices, look for reputable store-brand batteries. You can also find lesser-known battery brands, some for as low as $8 for a 20-pack of CR 2025 batteries.
Steps for Replacing a Mercedes Key fob Battery
Replacing a Mercedes key fob battery differs slightly depending on which kind of fob you have. Newer Mercedes models generally come with the Mercedes Chrome Key, while earlier ones are likely to operate with the SmartKey.
Mercedes-Benz SmartKey:
- Purchase two CR 2025 3-volt lithium batteries.
- Pull the sliding latch at the end of the key holder and remove the valet key.
- Slide the key into the open slot, push down, and take out the battery compartment.
- Remove the backing and replace the batteries.
- Reassemble the SmartKey. Test for functionality.
Mercedes-Benz Chrome Key:
- Purchase one CR 2025 3-volt lithium battery.
- Find the tab at the bottom of the key and pull on it to release the key.
- Press the key into the narrow, flat end of the fob to pop open the Chrome Key cover.
- Remove the existing battery and insert the new CR 2025 battery. Make sure the positive side of the battery is facing up toward you.
- Close the Mercedes Chrome Key back together with its new battery installed. Check that the key is functional and ready to get you safely back onto the road!
