Hey, hoping someone here can help. I have a '98 W210 E200 Merc and for some reason the electronic key won't let me into the car. The barrel key doesn't work either. Not sure what to do, I know it's a fairly common fault.
1- first use WD40 (some sort of lubrication and rust release) in the key barrels and do it multiple times and exercise the key in the barrels see if you could release them or at least one of them released. (make sure you give enough time, at least 5 min each time you spray into the barrels and keep exercising them)
2- Take the batteries from the key fob, clean with rubbing alcohol and then wipe them. Also clean the contacts in the key fob that touches the batteries. I would change the batteries to make sure, if they are too old.
Make sure keep spraying into the key barrels and exercise them to make sure they are released (this is for in case the key fob still does not work after cleaning)
There is no electronic door key on those cars. In case the remote fails, you have 3 mechanical locks (2 on doors + trunk) that also should operate the central locking. 1998 might not have driver door lock. Did you try all 2 or 3? Someone reported that later W210 have the option of central locks on trunk lock removed, but it is worth trying anyway.
Beware that the alarm will sound and you can quiet it by inserting the key/knob into ignition.
BenzWorld.org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information anywhere in the world. The site includes MB Forums, News, Galleries, Publications, Classifieds, Events and much more!