In this guide, you will find instructions on how to drain engine coolant (antifreeze) on Mercedes-Benz vehicles.
In this guide, you will find videos and instructions to help you replace the battery on all Mercedes-Benz keys.
If your Mercedes-Benz key buttons are broken, you don't need to buy a new key. In most cases, you can simply replace just the key shell. You can purchase a new Mercedes-Benz key shell online.
Watch the video above or scroll down below to find step by step instructions. No programming is required when changing the Mercedes-Benz key fob battery.
Chrome key with Round Panic Button
- Two CR2025 batteries
- Slide the black tab to release the metal key.
Remove the metal key.
- Use the metal key to unlock the key insert (part inside the key that holds the batteries) and slide it out of the key.
- Slide-out both batteries. Pay attention to the orientation of the positive (+) side of the battery.
- Install the new batteries by sliding them in.
- Slide the key insert into the key fob.
- Slide the metal key into the key until it locks.
Chrome key with TRIANGLE Panic Button
- Remove the metal key from the keyfob. Slide the release at the end of the key to slide out the metal key.
- Insert the metal key on the exposed slot to pry out the back cover of the key.
- Use a small flathead screwdriver to pry out the battery.
- Install the new battery in the key. The positive (+) sign needs to be facing out.
- Press the back cover and metal key in the key.
Black case key
- Slide the release at the back of the key to removing the metal key.
- Insert the metal key in the exposed gap to release the key insert (part that holds the batteries).
- As you keep the release pressed, slide out the inner part of the key.
- Remove the batteries. Note the orientation of the positive side (+) of the battery.
- Install the new battery. Slide the inner part back in the key. Slide the metal key back into the keyfob.
Key used in Pre-2000 models
This key is used in many models up to the model year 2000. It is also used in a few models after the year 2000 such as the SLK, ML, Sprinter, G models.
- Press the round chrome button to open the metal blade.
- Use your fingers to pry out the back cover of the keyfob.
- Remove the battery and install the new one. Pay attention to the (+) of the old battery. Install the new battery in the same orientation.
- Press the back cover back on the keyfob.
What battery do you need for the Mercedes-Benz key fob?
The most common battery used in Mercedes-Benz keys is a CR2025 battery. Battery size is listed below each key picture.