2018 MERCEDES BENZ C 300

What owners reported to NHTSA, ranked by how often and how seriously.

This is complaint data, not a random sample.

It only includes owners who chose to file a federal complaint, so it over-represents dramatic and safety-related problems and under-represents minor issues an owner just had fixed without reporting. Read this as what NHTSA complainants report most, not as this vehicle's true failure rate. Full methodology.

Component ranking

  1. #1

    engine internal

    14 unsafe, 6 annoyance

    20
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=3)

    • "CYLINDER 1 SPARK PLUGS IS DAMAGED DUE TO PISTON DAMAGE, HOLE IN PISTON. IF EXTRA DAMAGE IS FOUND ON TEAR DOWN, COMPLETE ENGINE REPLACEMENT. This is direct from the repair facilities reports. While driving my 2018 C-300 there was smoking out of tail pipe, a ro…"~62,000 mi, complaint #1786467
  2. #2

    other

    4 unsafe, 6 annoyance

    10
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=4)

    • "TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ C300 CONVERTIBLE. THE CONTACT STATED THAT THE FRONT PASSENGER SIDE FENDER BECAME PARTIALLY DETACHED FROM THE BODY OF THE VEHICLE. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF FORT WASHINGTON ([REDACTED ADDRESS], FORT WASH…"~7,650 mi, complaint #1498746
    • "TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ C300. WHILE OPERATING THE VEHICLE, THE CONTACT NOTICED A BURNT CRAYON ODOR INSIDE THE VEHICLE. THE ODOR MADE IT DIFFICULT TO BREATHE INSIDE THE VEHICLE. THE VEHICLE WAS TAKEN TO MERCEDES-BENZ OF GOLDENS BRIDGE (321 NY-…"~14,000 mi, complaint #1605374
    • "The contact owns a 2018 Mercedes-Benz C-300. The contact stated that while driving 70 MPH South on the interstate towards Miami, the front panel detached without warning. The contact pulled over to inspect the vehicle and became aware that the panel between th…"~83,000 mi, complaint #2239526
  3. #3

    engine cooling

    6 unsafe, 1 annoyance

    7
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • " Engine light is on recently on my 2018 C300. Car has 36000 miles on it. It is diagnosed as the valve for the crankcase ventilation. The actuator was blocked."complaint #1806124
    • "Engine light appears due to P052e code “positive crankcase ventilation regulatory valve”. Part failed prematurely and appears to be a common problem in make/model. May cause engine damage due to inability to clear combustion gases in the crankcase."complaint #1833893
    • "Error Code P052E Positive Crankcase Ventilation Regulation Valve Performance"complaint #1867903
    • "The fault code P052E71 is logged in the fault memory of the engine control unit. Cause: Possible cause: The component or the electrical actuation at the partial load crankcase ventilation valve (Y58/2) may be faulty or might not activate initially."complaint #1884723
    • "The check engine light came on with the error code P052E - PCV valve failure while the car is only driven for less than 38K miles. I am worried about the quality of the car/engine."complaint #1925232
  4. #4

    engine oil consumption

    3 unsafe, 1 annoyance

    4
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "My Mercedes C300 2018 only have 33k miles on it, but I was leaking oil and gas from the positive crankcase ventilation valve which is not environment friendly. As I know many other who own Mercedes also have the same problem."complaint #1797880
    • "Failed positive crankcase ventilator after 40,000 miles common problem regulating oil consumption to the engine. Causing oil burn, oil leak, inconsistent oil ventilation. Dealer is aware of the problem. Engine light is on with code P052E. Commonly reported pro…"complaint #1875149
    • "Positive crank case valve failure. Check engine light on. Mechanic started this was extremely common and a costly repair on lower mileage Mercedes Benz vehicles. Mercedes Benz forums also mention this is extremely common and frustrating. This happened at s…"complaint #1930863
    • "I have 33,000 miles on the vehicle and the check engine light came on. The code P052e came up Positive Crankcase Ventilation Regulator Valve Performance. I’m reading that many people have the same issue but there is no recall. Is there anything that can be…"complaint #1969048
  5. #5

    engine stall or no start

    4 unsafe

    4
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "WHEN AT A STOP THE ENGINE WILL NOT RESTART SOMETIMES. I HAVE TO START THE ENGINE MANUALLY. THIS HAS HAPPENED TO ME FOUR TIMES IN 5 MONTHS ."complaint #1626937
    • "My car engine shutoff at stop lights. it happened 3 times, the other 2 incidents happened at parking lots."complaint #1824441
    • "The code I received is p052e from the check engine light. This can cause the car to stall out mid way through driving and cause a potential fatal accident. This is a common issue across C300 And GLC benz."complaint #1891536
    • "My vehicle only had 31,000 miles and I experienced engine failure. I bought a new engine for 16, 500. 00 dollars. Mercedes Benz did nothing. I almost got in to several accidents because the engine completely stop on the interstate. Almost got hit by several ca…"complaint #2142441
  6. #6

    glass and windshield

    4 unsafe

    4
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=3)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated that after washing the vehicle, the contact became aware that the adhesive attaching the rear window to the convertible top had started to detach. Upon further inspection, the contact became aware…"~49,000 mi, complaint #2097630
    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated that the rear windshield had detached from the vehicle. The vehicle was taken to the dealer, where it was diagnosed that the windshield bonding had detached and needed to be responded. The vehicle…"~70,000 mi, complaint #1949717
  7. #7

    sunroof

    2 unsafe, 2 annoyance

    4
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=3)

    • "THE SUNROOF SPONTANEOUSLY EXPLODED OUT OF NO WHERE. SOUNDED LIKE A SHOTGUN BLAST."~30,000 mi, complaint #1679418
    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated while attempting to close the sunroof, the sunroof failed to close properly. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was…"~45,000 mi, complaint #1938273
  8. #8

    evap system

    2 unsafe, 1 annoyance

    3
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "at 67000 miles the check engine light came on and is was engine code p052e crankcase ventilation regulator valve failure. This failure will cause the ending to exhaust increased contaniments in to the air. This is a know problem by MBUSA and they have change…"complaint #1875147
    • "This particular model of vehicle has a well-known and documented failure of the PCV valve (Crankcase). This has not been identified by NHTSA to date. This should be considered for a recall due to the high incident rate of the P052E error code (valve failure) a…"complaint #1897502
    • "The check engine light has been coming on to indicate replacement of vent valve assembly According to the Mercedes Benz dealership. This is a commonly known problem in MB that they should replace and repair instead of charging customers $2k. My car has below 4…"complaint #1916374
  9. #9

    steering rack mechanical

    3 unsafe

    3
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "The contact owns a 2018 Mercedes-Benz C300. While driving at various speeds, the contact could hear an abnormal sound from the transmission. The vehicle was taken to a local independent mechanic where it was diagnosed that the rack and pinion needed to be repl…"~57,000 mi, complaint #2018704
  10. #10

    adas collision warning

    2 unsafe

    2
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=5)

    • "FORWARD COLLISON SYSTEM ($1700 OPTION) AEB, DOES NOT WORK AS DESCRIBED IN MB LITERATURE OR WEBSITE. IN MY OPINION, THE FORWARD COLLISION AVOIDANCE SYSTEM (AEB) IN MY 7 MO. OLD 2018 MERCEDES C300 SIMPLY DOES NOT WORK. I SPECIAL ORDERED THE CAR WITH THE 997 PKG…"~5,000 mi, complaint #1526103
  11. #11

    backup camera

    2 unsafe

    2
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "I recently purchased a 2018 Mercedes C300 and I noticed the rear view camera will not show an image. It mechanically will open and all other cameras are fully functional but the image will not show instead I see a icon of a camera in a red crossed circle. When…"complaint #2072521
    • "Rearview Camera is not displayed when the vehicle is placed in reverse. The display shows a black screen. A Recall Notice has been published for other vehicles of the same year, make, and model. The failure of the Rearview Camera results in safety risks during…"complaint #2137550
  12. #12

    control module

    2 unsafe

    2
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=2)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated that after starting the vehicle, the S.O.S. Not Active message displayed. The contact was concerned that in the event of an emergency, the emergency services function would be inoperable. The vehic…"~85,000 mi, complaint #1879221
  13. #13

    tire failure

    2 unsafe

    2
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "I WAS DRIVING ON HIGHWAY 1, AT ABOUT 45 MPH, ON MY WAY TO WORK IN A LIGHT RAIN. I MAY HAVE JUST TRANSITIONED INTO THE #1 LANE OF TRAFFIC AS I WAS ABOUT 500 FEET FROM THE RED LEFT TURN SIGNAL LIGHT WHERE I MAKE MY NORMAL TURN. I JUST REMEMBER MY CAR SUDDENLY…"~16,000 mi, complaint #1632719
  14. #14

    transmission automatic

    2 unsafe

    2
    incidents

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "I have a 2018 C class. Purchased it with 32k mikes 12/21. April 2022 I started experiencing issues. When I put my car in drive/reverse the gears shift it’s self back to neutral. When I’m stopped at a light it will take me out of drive and shift it’s self in ne…"complaint #1836458
    • "Transmission failed, yes available for inspection Very bad safety issue Yes it has been confirmed by dealship Yes by the deanship Yes there was warning lamps that appeared in January 2026"complaint #2216804
  15. #15

    abs module

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "While I was driving to work in a heavy rain my abs malfunction light came on in my car. I decided to take it to the Mercedes-Benz dealership in Fresno. They said it was the ABS module that needed to be replaced. After being in the shop for almost 3 weeks they…"complaint #1993077
  16. #16

    airbag system

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ C300W. THE CONTACT STATED THAT THE VEHICLE WAS REPAIRED PER NHTSA CAMPAIGN NUMBER: 18V838000 (AIR BAGS) BY MERCEDES-BENZ OF ARCADIA ([REDACTED ADDRESS], ARCADIA, CA 91006, [REDACTED PHONE]). HOWEVER, THE AIR BAG WARNIN…"~10,000 mi, complaint #1548164
  17. #17

    battery and charging

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "According to the dealership, if the car is not started every 3 days, it will shut itself down. The car was towed 6 times, I'm a business woman, my coworkers, friends drives Mercedes Benz, and no one have heard of any such issues. Any cheaper cars, after 2 week…"complaint #1925526
  18. #18

    brake hydraulics

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=2)

    • "I BROUGHT MY VEHICLE TO MERCEDES BENZ FOR A REAR TAIL LIGHT RECALL. WHEN I PICKED UP MY VEHICLE THE BRAKE PEDAL WENT TO THE FLOOR. NOTE: THIS WAS NOT HAPPENING PRIOR TO ME DROPPING THE CAR OFF TO THE DEALER. THE SERVICE MANAGER DROVE MY CAR BACK TO THE MEC…"~75,000 mi, complaint #1476840
  19. #19

    engine head gasket

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated while driving 35 MPH, there was white smoke coming from exhaust. The contact stated that the check engine warning light illuminated. The contact stated that after turning off the vehicle the smoke…"~54,000 mi, complaint #1804860
  20. #20

    engine turbo supercharger

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "Code P052E just like all 2.0 turbo Mercedes Benz engines will get. This is a engineering defect and the cars with these engines should be recalled. I have researched and read that even after repaired this expensive engine defect will re-occur about every 3…"complaint #1874291
  21. #21

    fuel tank and lines

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=1)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated that while the vehicle was parked inside the garage, there was a strong fuel odor inside the garage. The contact stated that there was fuel leaking from the vehicle. There were no warning lights il…"~52,300 mi, complaint #2064771
  22. #22

    infotainment head unit

    1 broken

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "Under hot ambient condition center console touchpad glass crack. There is a service bulletin TSB LI54.21-P-068464 for the issue but MB would not replace the part."complaint #1805919
  23. #23

    interior trim

    1 annoyance

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "This is 2018 Mercedes Benz - C300 and it seems across this model line up and models from that year it looks like headliner particularly fabric starts to separate from the pillars in the rear. Across google there is bunch of C300 with the same issue in the same…"complaint #1869107
  24. #24

    lighting exterior

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "Headlight is out and there is no replacement; dealer says they are having significant issues with headlamps. Also, tire safety monitoring system is always on, even though there is a proper air pressure amount."complaint #1831793
  25. #25

    mirror

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "TL* THE CONTACT OWNS A 2018 MERCEDES-BENZ C300. THE CONTACT STATED THAT THE EXTERIOR LEFT REARVIEW MIRRORS FAILED TO PROVIDE THE APPROPRIATE VISIBILITY. OBJECTS APPEARED AS THE MIRROR READS TO BE CLOSER ARE FURTHER AWAY, WHICH IMPACTED THE DRIVER. THE DEALER W…"complaint #1554566
  26. #26

    noise or vibration unspecified

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "Was sold Car Feb,27,2024 from dealership the car violently vibrates at 60mph took it to 3 Repair shops"complaint #2002400
  27. #27

    paint and clearcoat

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated while driving at approximately 65 MPH, there was a windy sound coming from the front of the vehicle. The contact then noticed the sound of an impact on the rear driver's side of the vehicle. The co…"complaint #1988843
  28. #28

    seatbelt and pretensioner

    1 annoyance

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "I have noticed the driver seat belt not retracting after usage. Upon looking online I saw a post about a recall. Called local Benz dealership and BenzUSA customer service both said my Vin is not part of the specified recall. "complaint #2134219
  29. #29

    software or update

    1 annoyance

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "To Whom It May Concern, I bought this certified preowned Mercedes Benz, and the recall is open. I have taken the car to the dealership, they deny me from service because its an over the air recall. The Mercedes Benz website clearly states on their letter for…"complaint #1756246
  30. #30

    steering column

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "RECALL LETTER STATES DEFECTIVE NUT IN STEERING COLUMN REPLACEMENT PART IS NOT AVAILABLE AND NO DATE IS GIVEN WHEN IT WILL BE AVAILABLE. LETTER WARNS IF THE PART (NUT)) CRACKS THERE IS A RISK OF A CRASH. MERCEDES FACTORY OR THE DELRAY MERCEDES DEALERSHIP T…"complaint #1540277
  31. #31

    steering electric assist

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "I AM WRITING TO SHARE MY DISSATISFACTION WITH MERCEDES BENZ. I HAVE A 2018 C300 THAT WAS PURCHASED BRAND NEW. THE STEERING WHEEL IS DETERIORATING AND I ADDRESSED THE SERVICE DEPARTMENT OF ONTARIO,CA. I OPENED A CASE WITH CORPORATE AND SPOKE WITH CASE MANAGER J…"complaint #1531126
  32. #32

    unknown

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=0)

    • "CODE'S P052W-71 & P060A-00 THESE'S CODES HAS BEEN AN ISSUE WITH MERCEDES BENZ FOR QUITE SOME TIME NOW... ITS BEEN COMPLAINTS AFTER COMPLAINTS AND MERCEDES BENZ HAS NOT TAKING OWNERSHIP OF THE ISSUE.. THIS IS DEFINATELY A RECALL PLEASE LOOK INTO THIS I CAN BE…"complaint #1977981
  33. #33

    wiring harness

    1 unsafe

    1
    incident

    Mileage: suppressed (fewer than 10 mileage-bearing reports; n=2)

    • "The contact owns a 2018 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, there was a message was displayed that there was a light bulb malfunction. The contact stated that the rear turn signal lights and brake lights were not…"~52,800 mi, complaint #1957390

NHTSA investigations

Search NHTSA's own recall and complaint database for MERCEDES BENZ C 300 directly.