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

Mercedes-Benz Key Fob on Table

If your Mercedes-Benz key fob isn’t working like it should, then it may be time to replace the battery. The expert technicians at Mercedes-Benz of Princeton are happy to show you how to change the battery in a Mercedes-Benz key fob! In the guide below from our service center, learn how to tell when your key fob battery is on its last legs and how to replace it at home in Princeton.

When To Replace Your Mercedes-Benz Key Fob Battery

How do you know when your Mercedes-Benz key fob battery is dying? Look for these early warning signs of a weak key fob battery:

  • Difficult Starts – If your vehicle takes longer than usual or multiple attempts to get started, a low key fob battery could be why.
  • Loss of Key Fob Functions – If the lock/unlock or panic features on your key fob aren’t working, it’s a sure sign that your key fob battery is kaput.
  • Charging System Dashboard Warning – Your vehicle may warn you about a low key fob battery with a dash warning that indicates a charging system issue.

If you experience any of the above, the best course of action is to be proactive! Change your Mercedes-Benz key fob battery to avoid further issues on the road in Hamilton. 

Replace Your Mercedes-Benz Key Fob Battery

If you’ve determined that your key fob battery is dying, you’ll just need to follow a few simple steps. Here’s how to change the battery in a Mercedes-Benz key fob:

  • Determine Your Mercedes-Benz Key Type – There are several types of Mercedes-Benz key fob battery, and the one your vehicle uses will depend on its model year. For example, newer vehicles use a Chrome SmartKey®, which requires a different battery change procedure than the older SmartKey®.
  • Get the Right Replacement Batteries – The Chrome SmartKey® takes one CR 2025 replacement battery. Older SmartKey® varieties take two CR 2025 batteries.
  • Replacing a SmartKey® Mercedes-Benz Key Fob Battery – To replace the battery in an older key fob, first pull the latch at the end of the keyholder. Then move the key horizontally into the open slot, and carefully lift the battery out of its compartment. 
  • Replacing a Chrome SmartKey® Mercedes-Benz Key Fob Battery – To replace the battery in a newer key fob, pull the tab at the bottom. Now, remove the key fob cover by pushing the key into the narrow end of the slot, and remove the battery.
  • Reassemble Your Mercedes-Benz Key Fob – Pay attention to the orientation of the battery when you remove it, and replace with a fresh battery. Then reassemble the fob casing the same way you took it apart.

Save On Your Mercedes-Benz Service Cost at Mercedes-Benz of Princeton

Need help with Mercedes-Benz maintenance between regular service appointments? We’re happy to help out, whether you’re cleaning leather car seats or checking your oil at home in Mercer County. Plus, you’ll pay a lower Mercedes-Benz service cost when you schedule service with us in Lawrenceville!

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