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pretty bad
Crashes / Fires:
0 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
7,040 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2015 Mercedes-Benz C300 miscellaneous problems

miscellaneous problem

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2015 Mercedes-Benz C300 Owner Comments

problem #5

Jun 112016


  • 9,700 miles


Multiple incidents of 'collision prevention assist plus inoperative'. car loses all power until restarted. This happened several times, once on an interstate at 65 mph creating a dangerous situation. I had to pull over several lanes on the interstate with no power while other cars had to avoid me. I brought the car into the dealer and after a week of repairs, the same fault has occurred twice in the first 24 hours after return of vehicle. Fault occurred at 60 mph during a passing maneuver on a 2 lane road. Again, we were put in a very dangerous situation. This is an unsafe vehicle. Attached is a picture of the dashboard fault that I photographed after the car coasted to the side of the road. The car would not move until I turned it off and restarted.

- Boulder, CO, USA

problem #4

Apr 072016


  • 10,500 miles
While driving "collision prevention assist plus inoperative" message appears on dashboard. Car loses its ability to accelerate. Occurred twice (January 2015) on city streets forcing me to pull over to the side of the road and restart my car, the error disappears and I am able to drive normally. 4/7/16 occurred while traveling 65mph on an interstate. I lost ability to accelerate and was almost rear-ended by a semi-truck. The vehicle was serviced at a Mercedes dealership on 1/11/16 the highway incident occurred after the "fix". it is currently back at the dealership being tested by the service department. I am told the current fix is to replace all the senors. I have opened a case with mbusa to repurchase the vehicle given the initial repair did not work and put me in perilous highway situation. I purchased the vehicle in October of 2015.

- Canonsburg, PA, USA

problem #3

Jan 202016


  • 8,500 miles
Two issues, purchased a certified pre owned vehicle. At 8900 miles, we noticed the car was idling very rough on a cold start, almost the sound of a diesel. The sound would resolve after 10 minutes of driving. Service informed us that there was a recall on the rods and pistons. We had the engine rebuilt, and the noise is the same, if not worse. The car sounds nothing like laterbuild '15 models or '16 models, nor does it run as smoothly. Secondly, 5 occurrences involved inoperative collision prevention assist warnings and inoperative anti-skid warnings appearing on the dash causing the car to reduce operating speed to 20mph max. Car needed to be shut off and restarted after a 5 minute period each time these warnings appeared, in order to drive over 20mph. The vehicle was serviced for these warnings twice. The first service diagnosed the car with a coding issue. The second, involved replacing modules. This all occurred during the two months of owning the car. We notices several similar complaints regarding the early build 2015 C300S, and decided to cut our losses and purchase another vehicle. We did not feel safe in that car.

- Watertown, CT, USA

problem #2

Jan 162016


  • 5,000 miles
Collision prevention assistance feature went on automatically ( as well as check-engine light) while driving at highway speed in normal weather. I was not in an accident, near another vehicle and completely aware and driving normally prior to this occurring. I had to struggle with car to pull over to shoulder, loss power from gas pedal, car hard to control. I had to turn off the car, deactivate the function to drive. It happened again when I drove the car later that day after the car had been parked for a while. Took it into service. They were able to find the error code.they found that Mercedes sent out a memo in Sept. 2015 stating they are aware of the problem but service is not to do anything to "fix" it! I have only owned this car for 6 weeks, bought it new and have less than 6,000 miles on it. Mercedes is not offering a solution but more of a wait and see attitude.

- Owings Mills, MD, USA

problem #1

Mar 062015


  • 1,500 miles
I had two issues within 2 months of buying the car earlier in this. I purchased the car in early Feb 2015. I heard a loud sound in the heating unit, then a small clicking sound ensued for over a week. Brought it in, the motor had blown, so they replaced it without a dime out of my pocket. Then in March, I was driving about 35 miles per hour when a very loud noise like bad breaks started and wouldn't stop no matter what I did. We towed it using Mercedes, but had to pay for an uber to the dealership. It was again another malfunction with the new model, and they fixed the breaks and rotors that same day without a dime out of my pocket. I now have 6500 miles on it since I got it in Feb this year, and the check engine light came on. I tried to replace the fuel cap but that didn't make it go away and the car is driving fine. Im bringing it in later this week. I saw reports that there are some cars with this fuel issue thats causing this indicator. Overall this one particular car I leased is a total dud, but I hope these reports help others with similar issues.

- Springfield, NJ, USA

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