Key FOB Stopped Working
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2012 E550 Cabriolet 2011 VW Eos 1985 Pininfarina Spider
Key FOB Stopped Working
My key FOB On my 2012 E550 is not working and I only have one. When I push a button on it a little red light by the panic button flashed. Any ideas?
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'13 GLK350 4matic,'10 C207,'15 GLA250,'07 Honda Odyssey, '18 GLE 43, '24 EQS 580
Thread Starter
Super Member
Joined: Jul 2017
Posts: 517
Likes: 59
2012 E550 Cabriolet 2011 VW Eos 1985 Pininfarina Spider
I tried jumping the car, but nothing. No crank or anything. I have some power in the car, interior and dash lights. Should I still be able to unlock and lock the doors with the key fob? The fob is not doing anything.
I was messing with the car this morning and accidently left the headlights on for 6 hours. When I came out the car would not start. IOs it possible the battery is dead to the point the FOB will not activate anything?
I was messing with the car this morning and accidently left the headlights on for 6 hours. When I came out the car would not start. IOs it possible the battery is dead to the point the FOB will not activate anything?
Last edited by Davery; Sep 5, 2024 at 08:54 PM.
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Joined: Jul 2008
Posts: 296
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2015 E400
Check out this video, hopefully it's as simple as replacing a fuse.
Worst-case, it could be EIS issues. There's also this link regarding EIS issues/diagnostics:
Everything You Need to Know about Mercedes Benz EIS Repair | The ECU Pro Blog (the-ecu-pro.com)
From the symptoms you've described, it sounds like the communication between the key fob and the EIS is broken. Batteries are only one possibility and it sounds like it's neither the car batteries or fob battery. Most likely a bad EIS board.
Apparently, if it's EIS, then that's not a DIY, the parts will be ~$750 US, dealer-only, and probably an hour of dealer labor? Probably about $1k total. I suspect this may be my issue as well, but it's been like this for over 6 years, so I haven't really bothered with it.
Hope the fuse fix will do the trick for ya!
Worst-case, it could be EIS issues. There's also this link regarding EIS issues/diagnostics:
Everything You Need to Know about Mercedes Benz EIS Repair | The ECU Pro Blog (the-ecu-pro.com)
From the symptoms you've described, it sounds like the communication between the key fob and the EIS is broken. Batteries are only one possibility and it sounds like it's neither the car batteries or fob battery. Most likely a bad EIS board.
Apparently, if it's EIS, then that's not a DIY, the parts will be ~$750 US, dealer-only, and probably an hour of dealer labor? Probably about $1k total. I suspect this may be my issue as well, but it's been like this for over 6 years, so I haven't really bothered with it.
Hope the fuse fix will do the trick for ya!
Last edited by pl626; Sep 6, 2024 at 06:40 AM.
