Electrical safety hazard that could lead to fire. Left rear taillight assembly unit melted due to improper ground due to faulty wiring harness. Talked with Mercedes dealership and was advised that this is a common problem with this car. I asked if there was a recall as this is a major safety hazard and was advised that no recall has been issues. Was told that this problem is so common that Mercedes has a repair kit but wants me to pay $200 to have the safety issue fixed. Mercedes refuses to do anything until someone is killed and forced to issue a safety recall to fix this defect. If you google 2009 C300 brake light recall you will find countless people who have the same issue including identical photos of the melted bulb assembly unit. I would hope for the safety of everyone that the ntsb could review this issue further before someone is serious injured.

- Gilbert, AZ, USA

The left rear tail lights stopped working. I had to replace the electrical harness attached to the bulb bracket. This was replaced on 2/13/2013. Exactly one month later, the right rear tail lights stopped working on 3/13/2013. I will have to replace the same assembly of parts. I have no damage to the rear of my vehicle. Mercedes Benz had a recall on the (Mercedes Benz M-class year 2009) for the rear lights.

- Upper Saddleriver, NJ, USA

Driving at night. Instrument warning of numerous failed tail lights on both sides at the same time. Pulled over and opened trunk. Trunk was filled with smoke and burning plastic smell. Observed electrical connectors on both tail light bulb holders melting and smoldering. Visual flame (small) on ground wire on right tail light connector. Observed both bulb holder assemblies and their electrical connectors heavily damaged by fire/heat only around the brown (ground) wires. Removed assemblies and was able to restore some tail light functions by cleaning electrical connectors of melted plastic. Noted corrosion around ground terminal pin of connectors. No indication of moisture or water leaks in area. No fuses blew. All bulbs good. Tail light operation now intermittent. Will contact dealer to replace parts - feel this should be a recall item due to fire and the circuit not being protected by fuse. Updated 3/28/13..updated 09-09-14

- Odessa, TX, USA

Warning indicators flashed for all the right side rear lights. When I went to change bulbs discovered the covering on wires had melted along with the plastic harness. Took it to dealer next day and the harness had to be replaced for a little over $150. It is happening on the other side also. Service rep has seen on other C300S. Mb denies this is a defect.

- Orlando, FL, USA

Warning on dash shows rr brake light is out and turn signal lights is out. Went to look at the back of the car to see if the lights where on and the rr light assembly was dim. Open the panel where the bulbs are and the wire harness was fried. This might be a fire hazard. Updated 03/27/13 updated 04/02/2013

- Bellevue, WA, USA

At some point in time the left rear taillight started to dim dramatically. I opened the enclosure to change the bulbs thinking they were burnt out and found the wire harness as well as the bulb dock had melted because of overheating. A fuse did not blow and the cars computer never gave any indication of this issue. My concern is that the system could actually catch on fire and it is in the trunk and not far from the gas tank. After researching on mb world this appears to be a known problem and flaw. I think it should be looked into and determine if there is a greater issue here.....updated 03/27/13 updated 04/03/2013

- Clarence, NY, USA

My car computer was showing a message that the right rear signal light, fog light needed to be checked. My husband changed the bulbs and the message was still there. These lights were no longer operating properly. Took the car for scheduled service and brought this to the attention of the mechanic at a Mercedes Benz dealer/auto service. He told my daughter that he removed the access panel and found that the connector to a bulb carrier, wire harness and bulb carrier were melted due to a short at the ground wire of the 7 pin connector. I called the service mgr he could not tell me or explain why this happened or its cause. Disappointed by his lack of knowledge and explanation of the cause, I contacted mbusa. At first the person that answered tried to brush me off " this can happen". when I insisted for a better answer or explanation she referred me to a "[xxx]"1-800-367-6372 ext.[xxx]. who stated that she would speak to other technical people and get back to me. When she got back to me, it was basically she was going to speak to the service mgr. At the dealership that serviced my car.he called me on 2/01/12 not clarifying the cause, just re-iterated what he had previously stated. I call [xxx] who simply stated that this has never been reported before, but it can happen, and stated that the dealership would give me a $200 discount at the next service date. I wanted an explanation of the cause, could this happen again, could this lead to further melting, that could lead to a fire, a bigger shortage, and possible accident. I was told by the mgr. At dealership, he cannot foresee the future and he could not predict if this would happen again. I was told that a defective part is not a major issue.no one offered to look further into the defective part and try and find out what really happen. If a part is defective, it should be evaluated or even ask for the part. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- Willis, VA, USA

At 5:00pm, I was driving the Mercedes Benz C300, year 2009, 9010 miles in the parking lot of ymca in la Canada, ca at 3 miles/hr. I prepared to stop the car and stepped on the brake, suddenly, the engine rev up and accelerated. The car jumped over the stop bumper but I pressed very hard on the brake and finally the car stopped and the engine was off. The front of the car was about 2 feet from the wall at the parking lot. I was so scared because it was the first time I experienced the unintended acceleration. I went to the gym and at 6:30pm I drove the car back home, it is about 6 miles from my house. I really feel unsafe with my almost brand new mb. I'll take off for work next Monday and will take the car to the dealer for checking. I was lucky this time with no damage or injury because I was driving very slowly in the parking lot and ready to stop. However I don't want to take the chance next time, it's so dangerous, I can get kill or somebody can get hurt if my car jumps again. I do the research and see the complaint # 10330370 on 05/23/2010. The case was almost the same: When the driver stepped on the brake and the mb unintended accelerated. Please do the investigation by now and feel free to contact me anytime.

- La Crescenta, CA, USA