How to Replace the Battery in a Mercedes Car Key?
3 Answers
The method to replace the battery in a Mercedes car key is as follows: 1. Push the small toothed switch at the end of the remote to the right to remove the mechanical key; 2. Insert a tool into the rear of the keyhole and pry to open the back cover; 3. Press lightly on the battery to remove and replace it. Mercedes models include: Mercedes E-Class, Mercedes A-Class, Mercedes S-Class, Mercedes G-Class, Maybach, etc. Taking the Mercedes E-Class as an example, its body dimensions are: length 5078mm, width 1860mm, height 1484mm. The Mercedes E-Class is equipped with a 1.5t turbocharged engine, with a maximum power of 135kw and a maximum power speed of 5800 to 6100 revolutions per minute.
I've got plenty of experience changing Mercedes key fob batteries. Having driven a Mercedes for nearly a decade, I always replace the key battery myself when it runs out. First, hold the key and look for a small indentation or button on the back—press it and the back cover will pop open. If there's no button, gently pry the edge open with a small tool like an old credit card or coin, being careful not to use too much force to avoid damaging the casing. Remove the old battery, usually a CR2025 coin cell—make sure you don't get the wrong model. When inserting the new battery, place it with the shiny side up (that's the positive pole) and align it properly in the slot. Close the cover and press firmly until you hear a click. After replacing, test the key by pressing the unlock button to see if the light turns on. I recommend buying original or reliable branded batteries—they last one to two years. After replacement, you can use a small tool to apply a bit of sealant to prevent dust. Overall, it's super simple—doing it yourself saves money and gives peace of mind.
I always change the battery carefully to avoid damaging the key. For a Mercedes key, first check the back for any grooves or buttons, then gently press to pop open the back cover, or use a blunt tool like a small screwdriver to slowly pry open the gap. Be careful not to scratch the surface and apply gentle pressure when prying. Remove the old battery and confirm the model is CR2025, then replace it with a new battery of the same type, ensuring the positive side faces up. After putting the cover back on, press firmly to ensure a tight seal. Test the remote function immediately after replacement to confirm it works. If unsure about the steps, it's safest to search for tutorial videos online and follow along. Regularly checking the battery level is recommended to extend the key's lifespan. Taking your time during the process is better to avoid accidental malfunctions.
