booboo8227

Thanks for the quick reply! I saw the comment on the gas pedal but it didn't seem definitive, plus I thought it was related but an odd root issue. Any idea on cost to repair?

joeyza

I couldn't tell you the price as the repair was done under warranty. My dealership has been pretty good with telling me an estimate on a specific request for repair (e.g. bent wheel was $150 to repair and when I asked they told me that ahead of time), but I suspect it is because of the relationship I've built with the service associates.

You might be able to call your dealership and ask for a verbal estimate for replacement of the accelerator module and pedal with associated labor. Some will answer you, some won't.

prujoe

*** Here it is a few years later and my 2011 C300 (W204) would display the "ESC Disabled" light when I accelerated too hard and acceleration and the ability to move out of the way of others immediately dropped to practically zero. Like you said, it could be quite dangerous. Thanks to you and this forum, I ordered the accelerator module for $140 after the Mercedes mechanic tried something else. I installed it in 5-10 minutes and it works like a charm. If you're still around here, thanks mucho.***

DFWdude

To be honest, I don't understand this problem. I haven't experienced this automatic disabling of ESC in my W212. But ESC is not required to operate the car, as I learned how to disable ESC manually in my older W203. Without it, throttle response is identical to before.

You may also get the "ESC disabled" message when changing batteries. It will go away when the car is started.

I'm almost certain that if you could disable ESC in the E, you would have no problem driving the car without it, meaning there's some other reason for the limited throttle.

Oh look, you can disable ESC in the W212, too.

pezzy669

Oh absolutely you can disable it manually and the car will drive fine - the issue here is the car would be getting erroneous/implausible signals from the accelerator pedal assembly and send the car into limp mode and shut down all the nanny systems until the next restart.

My '11 E350 would only do it on full throttle acceleration and it was game over until you shut down and restarted, it was always the worst times too because when you are going full throttle you are most likely in a maneuver where you need the power to safely complete your maneuver. Only to have the car just shut down on you and leave you hanging because it was getting bad signals from the accelerator pedal.

I think I paid ~$150 for the accelerator assembly from the dealership, its one nylon bolt nut and one electrical connector. Took me all of 5 minutes to replace and the problem was fixed - no more limp mode at full throttle.

TeeEl

Are you sure that the light isn't for the ESC engaging? The light coming on should mean the ESC is kicking in and stabilizing you. The "ESC Disabled" should come on as a message on your dash console.

jonasrf

Hello all;

I am new to this forum, thanks to everyone who takes the time to participate and answer questions.

This time i have a question, I have the same problem, my car E500 2011 disables ESC "ESC inoperative" i used star diagnose to check pedal and found it was ok, passed all tests, however i read faults for throttle valve, and it did not pass the tests for the throttle valve. is this a common problem? I do not find anyone else with problems in throttle valve. I do not want to throw in parts just to find out it was a wiring problem.

thanks in advance

prujoe

Jonas,

After doing some research and speaking to Mercedes owners, I ordered an OEM accelerator pedal on 2/8/2019 from AutohausAZ for $140.48 and it worked perfectly. It didn't seem to make sense to me and my MB owner-neighbor thought it was crazy, but I haven't have any problems since. I have a 2011 C300.
Joe P

jonasrf

Thanks Joe,

I will switch the pedal with a friends car, same car one year older, appears to have the same part number according to EPC, will let the forum know the outcome. I still do not think this will solve the problem as i tested the accelerator pedal with star diagnose and showed everything working fine, however totally worth it before buying $1000. dollars throttle valve.

jonathan s

diesel_dan

Just wanted to +2 on this being the accelerator pedal. This has happened Twice on our car, but since it has more electronic safety features, a heck of a lot more stuff was shutdown when this occurred (pre-safe brake, distronic, ESC, blind spot, etc.). It always presented on full throttle application (pedal down to kick-down). Went into Limp Mode, but If you pull over and restart it all went back to normal. First time Dealership diagnosed the pedal assembly but only replaced pins within the assembly. 2nd time, about a year later, the dealer replaced the entire assembly with a new one and the issue has not (yet) returned...

Wanted to share my similar symptoms with the similar fix others have found...

jonasrf

So finally I was able to swap accelerator pedal with my friends car, checked and exactly same part number. The error is still there, apparently i will have to change throttle valve, I found Cardone has rebuilt valves for only $220.. I will give it a try and keep you posted.

jonasrf

So finally got my throttle valve from cardone, changed it, did the relearn with sds, after 10 minutes idling, the car went into limp mode again Esc inoperative unable to accelerate...

the only faults i get with sds are regarding the throttle valve, the faults i get for ESC only say that they are caused by a fault in motor Electrónics...

anyone out there that may be able to help,

apparently not the pedal and not the throttle valve... i am completely lost in diagnosing...

thanks
in advance!!!

jonasrf

Just an update, I just hate to read unfinished threads when nobody shares how they fixed their cars, .

So.... I read lots of threads all over the internet for many mercedes having the same problem. After taking the car to the dealer and having them recheck everyhing i had already changed, the part that had failed was the ECU motor electronics. Further reading through the internet showed that i was not the only one with a faulty w212 v8 failing ECU. Other thing you may notice as well, is a random Engine light coming on and then turning off after a few days. in my case it always showed problems with Oxygen sensors, however when tested they passed all tests every time, i was ok living with that. I had diagnosed myself either a bad wire harness which I tested and appeared to be ok, or a bad ECU which i was afraid to mess up with and decided to take it to the dealer.
Remember ECU must be installed by the dealer as they have to program it. Changing it is really only plug conectors, but buying and programming must be done at the dealership.