craigc

Hi Everyone, I bought a W211 with only one key. Got it home and later the key fob quit working, yes I put new batteries in it. I thought I was screwed because I live 2 hours from the MB dealer and to get a new key you have to have the car at the dealership.

So I got thinking I have nothing to lose so here's what I did and now I have a working key fob. Our toaster oven has convection so that's what I used but it should work in a regular toaster oven or oven.

These are photos of an old key with components missing that I bought a while ago but used it for illustration purposes.

Hope this helps someone, let us know if it gets a broken key alive for you.

- remove the circuit board from the case by pulling on the white tab you can see after you remove the battery holder.
- remove the white plastic keeper off the circuit board.
- put the circuit board in the toaster oven or oven with the side with the largest components facing up then set to 400 deg F
- start the toaster oven and watch it until it hits 400 deg F then time it for 60-90 seconds.
- after time is up shut it off then open the door and if you can slide the tray out to help cooling. Be very careful not to jar it because remember the solder has just melted / reflowed and you could have components fall off.
- let it completely cool and put it back together and try it with new batteries.
- DON'T tell your wife you're doing it in her oven.​​​​​​