1. Retrieve the Key:
- Press the button on your key fob to release the mechanical key.
- Pull out the mechanical key from the fob.
2. Locate the Battery:
- Take a small flathead screwdriver and carefully pry open the case of the key fob, starting from one of the corners.
- Gently separate the two halves of the key fob, revealing the battery inside.
3. Remove the Old Battery:
- Use the flathead screwdriver to gently pry out the old battery.
- Be cautious not to damage any internal components.
4. Insert the New Battery:
- Check that the new battery is the same type and size as the old one (usually CR2025 or CR2032).
- Position the new battery with its positive (+) side facing upwards, exactly like the old battery was placed.
- Press the battery firmly into its compartment.
5. Reassemble the Key Fob:
- Carefully align the two halves of the key fob.
- Press the two halves together until the case snaps back into place.
6. Retest the Key:
- Reinsert the mechanical key into the key fob.
- Press the buttons on the fob to test if they're working properly.
- If the lights and/or buttons are not functioning properly, check if the battery is seated correctly and that the contacts are clean.
Remember, replacing the battery in a Mercedes-Benz ML320 key fob is generally a simple task and doesn't require any specialized tools or skills. However, if you encounter any problems, it's always best to consult your vehicle's owner's manual or seek assistance from a qualified technician.
