VPC_E63S

So both keyfobs stopped working. Cannot unlock or lock the car. The fob has to be placed in the console in order to start the car, otherwise not detected. I replaced the battery, but given that both fobs went bad at the same moment, I assume something is wrong with the car. Any easy fixes? Bad fuse or similar I should check? Tnx

Lucabratsi

Hello,
I have a similar problem with one of my fobs. About 6 weeks ago it started eating batteries once a week. Have you tried changing the battery? Took it to dealer. unfortunately I just changed the battery so dealer said nothings wrong. Dealer said the fob actually goes into sleep mode if its in your pocket, and too many or prolonged button presses. Suposedly to wake it up I was instructed to you have to be by the drivers door with the sleeping fob, then touch and operate the door sensors. Well interestingly enoug, the fob started to unlock the doors. However, it could not start the car. So I am requesting a replacement fob. Try to wake up yours, do the door sensor wake up, put it in the special spot and leave it there for a few minutes but make sure you disconnect and detach the manual key. See if that does anything.
cheers

VPC_E63S

Thanks Luca. So I did replace the battery - which didn't work. The weird thing is that it is both fobs. I.e., my fob stopped working yesterday morning. I couldn't start the car without putting it in the console and then couldn't lock the car when I got to work (had to use the app). Changed the battery. No avail.

Then when my wife came home - her fob similarly didn't work. So assume this is something in the alarm system or otherwise on the car.

Lucabratsi

Hello,

Then I must be the cars receiver control module.
Needs a dealer visit. Let us know how you make out. I will update when I go back for my failing fob also.
Cheers,

gearFX

I think the receiver is in the center console tunnel, by your right knee (assuming left-hand drive) to the left of the cupholder area. Did you by chance install a new phone mount/cradle or other similar object near that location with metal components? Or put a big YETI insulated mug in the left cupholder? I found that the Mercedes key fob reception goes to hell if any metal is near that location, and is immediately restored once the interference-causing obstruction (which may also act as a radio wave shield?) is removed.

VPC_E63S

Here is the resolution (for now, at least). Apparently some wire (in the headliner) was "chafing" against the body and shorting out the circuit. Sounds hard to believe, but that's what they told me. So the fuse would keep blowing every time they replaced it. So now fixed and note that this also was affecting the mirror folding - so that was not a software problem either.