Do it yourself
Frequently asked questions about cars and motorcycles
Car tutorial (Do it yourself) Motorcycle tutorial (Do it yourself) Frequently Asked Questions

Remote Key Battery Replacement

Model: Mercedes Classe E W211 - Years 2002-2009
Part: Key

To replace the batteries (usually two for Mercedes) in the remote key, you do not need to open the shells; instead, there is a sort of drawer on the back of the key that can be pulled out. First, extract the metal key by pressing the locking mechanism; then slide out the drawer containing the two batteries; measure the voltage of the old batteries with a voltmeter to check their actual wear; then install the new batteries, ensuring the correct polarity, insert them back into the key, and reinsert the metal key. To test the operation, point the remote at a cellphone camera and check for the infrared signal by pressing the buttons.

Updated on 10 February 2026 by ScegliAuto

Video tutorial

Related tutorials

Replace Key Battery on Mercedes E
Replace Key Battery on Mercedes E
Mercedes Classe E (2002-2009 / W211) Take the key remote and slide the button to release the metal key. Once extracted, use it to apply pressure on the key cover. Press until the piece s…
How to replace the battery of the Mercedes W211 remote control
How to replace the battery of the Mercedes W211 remote control
Mercedes Classe E (2002-2009 / W211) Today we will explain how to replace the battery of the remote control of the Mercedes E-Class. The first step to take is to press the button on the …
How to Replace the Key Battery in a Mercedes
How to Replace the Key Battery in a Mercedes
Mercedes Classe E (2009-2016 / W212) Removing and replacing the battery in a Mercedes key follows the same procedure used for many other car keys. To remove the battery from the key, fir…

Other guides you may be interested in

How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

Watch the video!


by ScegliAuto

More videos