Three problems related to headlights have been reported for the 2010 Mercedes Benz C300. The most recently reported issues are listed below.
Mercedes benz C300w light bulbs are constantly blowing out. Primarily due to the heat accumulation in the headlights. The plastic parts are melting, dry and very brittle which causes bulbs to overheat and blow out. Left & right parking lights(4), side lamps(2) and license plate lamp(2) have been changed out at least 15 times per lamp. The dealership suggest I change out the head lamp casing costins approx. $2k with labor. Aftermarket $700 plus labor. The service department at three seperate shops have stated this is a common problem with the mb C300.
A little less than a year ago my driver side inner parking light bulb failed, and about a week later the passenger side inner parking light bulb failed as well. When I went to replace them, the bulb and headlight assembly showed visible damage from where it appeared as if both bulbs caught on fire and melted into the headlight assembly, permanently damaging both driver and passenger headlight assemblies. There was the presence of charring on the bulb socket as well. I took the vehicle to the local Mercedes Benz dealership and they stated there was nothing they could do except to replace both headlight assemblies. If it were merely one bulb that failed in this manner, I would have chalked it up to maybe a faulty bulb or socket, but it is very odd that it occurred on both inner parking light assembly. Fortunately.
My car will be parked and engine not running and at any given time the upper front headlight on passenger side and the botom part of the rear tailight on passenger side will illuminate for no reason. It doesn't matter which position the lights are in.