amar.rai87

Hey Everyone,

Vehicle: 2010 Mercedes C300

I'm having a problem with my left tail light which is driving me crazy. I receive an error on my dashboard which states "Check Left Rear Turn Signal"

The strip of LEDs on my tail lamp do not flash. They also do not flash when I have my hazards on. However, the top brake lamp flashes instead.

I initially thought this was a damaged tail light, so I bought another and am receiving the same error. Anyone experience this before?

AZN Optics

Might not be the tail lamp, but the wiring harness. Check the ground wire for burn marks or brittle wires. There was a TSB out on those.

amar.rai87

I actually had the recall done on my tail lights last year, so I'm not sure if thats the problem. I really don't want to take my car into the dealership since they charge 180 dollars just to look at the car.

AZN Optics

Well, as you have a new tail light, I don't think it's an issue with the tail light itself. Either the harness or the rear SAM would be the most likely culprit.

Demvang

Did it work properly before the recall trip to dealership and after that? Is the tail light OEM or aftermarket? Looks like the wires are in the wrong plug slot, just my guess.

amar.rai87

Tail light worked perfectly before the recall. Is it possible to fix the harness by swapping out the cables? Does anyone have a pin out diagram of which colour goes where?

MDMercedesGuy

Doesn't Mercedes use a light replacement technology where it will replace a light with a nearby light if a bulb is out? I seem to remember reading something about this a while back.

teja1936

Would you believe it, I too have the same issue with the same vehicle. Australian delivered 2010 C300 with Dynamic Sports Suspension option.
I replaced my tail lights with OEM face lift tails and also replaced the rear SAM back in January of this year. Everything was going well no issues at all.
About a month ago the COMAND system started to develop issues in that it would inexplicably turn on and off for no reason. The screen would open, cycle through the warning message, the MB logo and then would shut down. It would do this continuously and then just stop. Despite repeated attempts to turn on the COMAND system it would not. I’d lose sat nav and phone capabilities. I took the vehicle to the dealership and could not replicate the problem despite it occurring repeatedly during the preceding days and weeks. The dealer thought that it may be a SAM issue and advised that if it needed replacing I’d be looking at $2000 + labour.
I left and nothing had occurred till Tuesday when the COMAND system started it’s routine of turning on and off again. In addition, (vehicle has the Dynamic Sports Suspension option – i.e. the SPORT button) the car was constantly switching between the ECONOMY mode and the SPORT mode. I could not even override the SPORT mode by depressing the SPORT button.
Last night I drive off, still no COMMAND system and I get 3 error messages - check rear left brake light, check right rear brake light and check third brake light. I get home and check and all lights are functioning. This morning I drive off and get the same 3 error messages plus an additional 4 - SRS malfunction, right side airbag inoperable, left side airbag inoperable and check left rear turn signal. I return home and check and the brake lights work, however, the left LED’s do not flash, but the top brake lamp flashes instead – same situation as amar.rai87. The right rear LED’s are operating as normal. Has it to say, I bailed out on the car and took my wife’s car to work instead.
Thanks in advance as I too am frustrated for a solution, if anyone has one or a suggestion.

williamq

I have both you guys' symptoms recently on my 2010 C300. For teja1936's issue, I replaced the battery and all error are gone except rear turn signal.
Did amar.rai87 fix the problem?

amar.rai87

So it is fixed now. It actually turned out to be a damaged tail light. The replacement one I had originally bought was defective as well. I bought it online and the seller did not disclose this information to me.

Here is what I suggest. Take a voltmeter and take readings at the terminals when the indicator is engaged. If there is voltage present, the strip of LEDS in the tail light are damaged.

williamq

OK, I will try that. Thank you.

Captain Carotid

I got sylvania bulbs turning light bulbs for the rear and maybe that is causing this issue. I am installing some high performance LEDs later today to see if that fixes the issue.