BF3PDZ

The CEL just came on this afternoon on my 2 year old C 250. only done 4700 miles. The car started fine and drove fine in the morning, and even when the light came on, it still started and run like normal, no unusual sound. My dealer said the earliest they can book me in is in 4 weeks time, which is a complete joke. The road side technician said it is a fairy common problem with the W205. At this point it seems like a minor issue but it could be a range of things, so just wondering if anyone here who is more familiar with this issue can give me an idea of what is the most likely cause.

49erPV

Might want to check and make sure the gas cap is on tight. If not, it will trigger the ECL.

Abohunu

Happened to me too long ago, CEL and car was running normal.
Without any appointment, I took it to the dealer and they removed the CEL. They told me that may be something with the fuel quality, I really don't know, but since then the CEL never came back.

o/

Terminator1

I'm wondering can they turn off CEL forever... I mean, not to be present even if it should...

Abohunu

Really I don't have idea, but they took like 5 min to remove that CEL.

Terminator1

And it never showed up again, not even because of bad fuel?

BF3PDZ

Thanks for the replies, I started the car again this morning and the warning light is gone. Drove it for the whole day and it hasn't shown up since, hopefully it will stay that way.

Abohunu

Nop never saw a CEL again since then.

ajb723

my light came on twice in the past 2 months, each time when the gas tank was relatively low (about 1/8th tank). There was no sign of trouble or weird noises. Each time the light went out after filling the tank. ( I had checked the gas cap each time and it was on tight).

kleinebin

Mine has come on twice since I had the car. I called Roadside and they said if I didn't notice anything different while driving, it's fine. They sent a roadside tech to my house who on both occasions plugged in their machine, couldn't locate a fault and it went away on it's own.

BF3PDZ

The MB roadside assistance is an absolute joke, they sub contracted to another company, and when the guy eventually showed up, he didn't have a scanner, and all he did was open the bonnet, had a look and went back. That was it.

Abohunu

Ohhh well.
the CEL light appear again since almost 2 years since first time, and is gone again!
I'm not sure this will work for you all, but I was in a red light, I activated the HOLD function pressing the break really hard, and woaaala! CEL is gone
No idea what happened, but now is gone in the precise moment I activated HOLD.

I hope this helps.

best regards.

Unnimon

I just saw the CEL turned ON this morning. Car did not show any signs of a failure though. It drove and sounded fine. Opened and closed the fuel cap multiple times, but the CEL is still on. I have taken it straight to the Service Center. Let's see what they say. The car is spending it's 50th day at the service center today (in a total span of around 36 months). Wow.... What a car ! I am blown away by the fact that a car can be so unreliable even in 2018. Reminds me of my grandfather's car that used to have starting trouble every other morning. I thought those day's were gone. But NO, buy a W205 C300 and you can relive those days. Brilliant thought from the part of the manufacturer, I would say.