Home · 2020 Mercedes-benz C-class Cabriolet · Complaints

What 45 owners told NHTSA about the 2020 Mercedes-benz C-class Cabriolet

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (45)Crash / fire / injury (6)Engine (9)Transmission & drivetrain (7)Backup camera & sensors (4)Body & structure (4)Electrical system (4)Fuel system (4)Airbags (3)Driver assistance (3)Steering (3)Visibility & wipers (3)

Newest first · 45 complaints · page 2 of 2

Apr 11, 2023Backup camera & sensors

The contact owns a 2020 Mercedes-Benz AMG C43. The contact received notification of NHTSA Campaign Number: 22V232000 (Back Over Prevention) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was made aware of the issue. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.

NHTSA ODI 11516496

Feb 4, 2023Transmission & drivetrain

Car randomly goes into neutral despite being in D drive mode. Often at stop light, after the light turns green, the car revs up but is not in gear despite in 'D' drive. I have to shift to park or turn car off then on to get it to go again. This has happens multiple times since new. This is very random and distressing when it happens. Car has been evaluated multiple times at the dealership. There are no trouble codes thrown. The car otherwise works and has no other problem. The technician (off the record) told me there is a known issue when he contacted Germany. Official response to me is that it is perfectly fine.

NHTSA ODI 11505594

Dec 13, 2022Transmission & drivetrainEngineFuel system

CEL with multiple cylinder misfires. Oil leak on top side of engine bank 2 in valley of injectors. Multiple codes for turbo charger faults and also clogged catalytic converters. Dealer confirmed and manufacturer denied federal emissions warranty on vehicle. Due to a modification that plays no role in the power train.

NHTSA ODI 11497171

Oct 25, 2022Fuel systemDriver assistance

The component that failed was the fuel injector and spark plug. A few months prior to this incident, I was making a left hand turn, when the accelerator completely gave out. I was making the left on a blinking yellow arrow, luckily the on coming car was not coming at me fast or I would've been in an accident due to the accelerator failing. I had to pull over, turn the car off and then back on to reset it. I was told by the dealership service center that they could not find anything and that there have been no complaints or recalls. After about 8 months of owning the vehicle, it started to have problems turning over when the engine on/off button was pressed. I was repeatedly told that they could not do anything if it did not happen in the dealership service center. This past week on 10/20/2022, while I was driving down the freeway, when I went to accelerate and at that moment the vehicle began to stutter/shake uncontrollably. After that, any time the accelerator was pressed it would shutter/shake. My vehicle was towed to a dealership. Come to find out, cylinder one was coding. They found out that the fuel injector was stuck open. According to the service advisor, that issue was causing a misfire. I was told that they replaced the fuel injector and the spark plug. According to the vehicle report I was given, 1 reman injector, 4 TS spring F In, 1 spark plug, and there was a core return (not sure what that means). The check engine light came on right away. In addition to the incidents above, I have had the forward collision alert come on when nothing is in front of me. I worry that one day it will cause my vehicle to engage the brakes when nothing is around.

NHTSA ODI 11490902

Oct 20, 2022Backup camera & sensors

******* DELETE VOQ ******* THIS COMPLAINT IS BEING MARKED FOR DELETION BECAUSE THE CONSUMER PLACED THE REQUEST.*DJR ******* DELETE VOQ *******

NHTSA ODI 11490119

Jul 25, 2022Backup camera & sensorsCrash

The contact owns a 2020 Mercedes-Benz C300. The contact was reversing out of her driveway at 3 MPH, the contact was using her rearview camera. The contact stated that the image froze and she crashed into a parked vehicle with the rear passenger side bumper of her vehicle. The contacts bumper was scratched and dented. The other vehicle had sustained a large dent in the driver’s side door. The contact stated no warning light was illuminated. The contact had taken the vehicle to a local repair and not a dealer or an independent mechanic. The vehicle had been repaired cosmetically. The manufacturer had not been informed of the failure. The contact had received the manufacturer recall letter and related the accident to NHTSA Campaign Number: 22V232000 (Back Over Prevention). The failure mileage was approximately 6500.

NHTSA ODI 11475739

Jul 19, 2022Tires

OEM tires that the Mercedes Benz dealership diagnosed as having shifted belts. 245/40 R18

NHTSA ODI 11474717

Jul 9, 2022

Vehicle is trying to be sold with this condition

NHTSA ODI 11473023

Jun 14, 2022Backup camera & sensorsCrash

The contact owns a 2020 Mercedes-Benz C300. The contact stated that suddenly the vehicle's sensors were illuminating and activating a warning stated that the sensors were defective. Many of the vehicle's sensors began to deactivate and malfunction. While reversing out of a parking space the rear view camera and sensor system failed causing the contact to crash into another vehicle. Both vehicles were damaged. A police report was filed. There were no injuries reported. The vehicle was not towed. The contact took the vehicle to a repair facility and stated that there was damage to the internal sensor and camera system. The contact took the vehicle to the dealer however the vehicle had not been diagnosed or repaired as of yet. The contact then received a recall notice NHTSA Campaign Number: 22V232000 (BACK OVER PREVENTION) however the VIN tool confirms remedy not yet available. The manufacturer was not made aware of the failure. The approximate failure mileage was 3,000.

NHTSA ODI 11469155

Feb 18, 2022Driver assistanceCrash1 injury

Automatic emergency braking system & forward collision warning. I experienced a medical emergency and blacked out, hitting 3 cars. The incident happened the morning of Dec. 31, 2021 and my car still has not been evaluated by Mercedes. I was taken to the ER and spent 3 days in the hospital.

NHTSA ODI 11452817

Aug 6, 2021Airbags1 injury

On July 17, 2021 I was driving at the posted rate of speed down I-275 Southbound here in Michigan. All of the sudden and without warning, there was a loud explosion which happened, from as near as I can tell, in the driver's side windshield pillar, where there is an airbag. No warning lights came on, and the car did not change its driving characteristics. Only after I reached my destination and searched under the dash, and every where else (including the exterior), did I find that the plastic "cover" on the pillar is pushed away from the pillar and much more loose than the plastic cover on the passenger side. Since the incident, I have had severe tinnitus in my left ear which was about 15-18" away from it. The air bag did not deploy. I did not hit a pothole, did not hit a bump, did not hit another vehicle.

NHTSA ODI 11428078

Jul 12, 2021

My car has failed to accelerate after being stopped. The first time, I was attempting to enter a shopping center parking lot by making a left turn across a busy road. When I engaged the gas pedal, the car finally got to 5MPH when I got into the parking lot. It was unsettling sitting in the road watching cars coming to you!! Then it did it again last week at the entrance to our complex. That time, I just turned it off and restarted it and it was fine. If it had not moved, I would have had the entire complex entrance blocked. I took it to Mercedes-Benz of Athens on 7/8 for 10,000 mile service. I informed them of the issue. The outcome this was "we unplugged a few things and hopefully this resets things". If you have the issue, bring the car in again! WOW!!! Is this before or after someone broadsides me? I think a vehicle that can not be depended on to accelerate when needed is dangerous to drive!

NHTSA ODI 11424403

Jul 1, 2021SteeringCrash2 injuries

While driving on the turnpike without warning my steering locked and I lost control of my car.

NHTSA ODI 11423100

May 25, 2021Electrical systemCrash

The contact owns a 2020 Mercedes-Benz C300. The contact stated that her son was driving at an undisclosed speed when another vehicle's muffler detached and crashed into the undercarriage of the contact's vehicle. The front driver and passenger side tires exploded and fractured the rims. The contact stated that the vehicle's alert system failed to warn her son of the incoming object which resulted in the collision. The contact's son did not receive medical attention. A police report was filed. The vehicle was towed to the dealer and repaired. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was 6,000.

NHTSA ODI 11418528

Jan 26, 2021Fuel system

THE FUEL SMELL IS COMING FROM THE RUBBER FUEL, THEY ARE NOT COVER BY MY CPO- WARRANTY ( 3000 USD PAID PACKAGE). I FOUND OVER 100 FRIENDS ON FACEBOOK GROUP HAS THE SAME PROBLEMS. DEALLER REFUSE TO COVER. MY KID IS FELL BAD ABOUT THE SMELL LEAKING.

NHTSA ODI 11390106

Dec 31, 2020Lane Departure

ON A NUMBER OF OCCASIONS, I HAVE RECEIVED AN AUDITABLE WARNING, AND A RED LIGHT ON THE DASH THAT DISAPPEARS AS QUICKLY AS IT HAPPENS. I CANNOT CONTRIBUTE ANY CAUSE FOR THE WARNING AND THERE ISN'T ANY RESIDUAL INFORMATION ABOUT THE SOURCE OF THE WARNING.

NHTSA ODI 11385957

Dec 10, 2020Engine

MY 2016 C300 (IN-LINE 4 TURBO, "PETROL" WITH 241HP) AT 55K MILES HAD 1ST CYLINDER CRACKED WHILE DRIVING ON HIGHWAY, AND MY CAR IS OUT OF WARRANTY. I TALKED TO MY DEALERSHIP AND THE CORPORATE SEPARATELY. THE DEALERSHIP WOULD COVER THE COST OF THE PARTS WHETHER THE ENGINE NEEDS REPLACEMENT OR NOT, AS I BOUGHT MY CAR THERE NEW AND HAVE BEEN USING THEM THROUGH PREPAID MAINTENANCE. I DECIDED TO FIX THE CAR AND PAY THEM PRE-ARRANGED LABOR. BUT HERE IS THE RESPONSE FROM THE CORPORATE: THANK YOU FOR YOUR EMAIL TO MERCEDES-BENZ USA, ALTHOUGH WE REGRET TO LEARN OF THE CIRCUMSTANCES THAT PROMPTED YOUR CONTACT. WHILE WE UNDERSTAND YOUR CONCERNS, ALL WARRANTY DETERMINATIONS ARE PROVIDED BY AN AUTHORIZED MERCEDES-BENZ DEALERSHIP UPON INSPECTION. IF THE WARRANTY HAS EXPIRED, THERE IS NO OBLIGATION ON PART OF THE MANUFACTURER, TO COVER THE COST OF REPAIRS. CUSTOMERS CAN REQUEST GOODWILL ASSISTANCE, HOWEVER WHICH IS REVIEWED ON A CASE BY CASE BASIS AND NOT GUARANTEED. IT MAY BE HELPFUL FOR YOU TO KNOW THAT WHEN REVIEWING YOUR CONCERN, THE VEHICLE REQUIRES AN INSPECTION AT AN AUTHORIZED MERCEDES-BENZ DEALERSHIP, AND THE FOLLOWING VARIABLES WOULD BE TAKEN INTO CONSIDERATION: VEHICLE AGE, MILEAGE, VEHICLE HISTORY, SERVICE/REPAIR HISTORY (WHETHER MAINTENANCE IS PERFORMED AT MB DEALERS), AND BRAND LOYALTY. REVIEW FOR GOODWILL REQUESTS CAN ONLY BE REVIEWED PRIOR TO REPAIRS BEING PERFORMED, AS REIMBURSEMENT IS NOT POSSIBLE. WE APPRECIATE THE OPPORTUNITY TO RESPOND. THERE MAY BE MORE CASES AS SHOWN ON THIS FORUM: HTTPS://MBWORLD.ORG/FORUMS/C-CLASS-W205/731642-W205-C300-STAY-AWAY-PISTON-CRACKED-65-K-MILES-5.HTML

NHTSA ODI 11382939

Oct 1, 2020Latches & locks

TL* THE CONTACT OWNS A 2013 MERCEDES-BENZ C300. THE CONTACT STATED THAT THE DOOR HANDLE WAS FRACTURED INTERNAL AND UNABLE TO BE OPENED FROM INSIDE OF THE VEHICLE. THE CONTACT STATED THAT HER SON WAS LOCKED INSIDE THE VEHICLE AND UNABLE TO EXIT. THE CONTACT INFORMED HER SON TO USE THE KEY FOB TO EXIT THE VEHICLE. THE VEHICLE WAS TAKEN TO AN INDEPENDENT MECHANIC AND WAS DIAGNOSED WITH A FRACTURED INTERNAL DOOR PANEL WHICH CAUSED THE DOOR HANDLE TO BECOME INOPERABLE. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT CONTACTED OR INFORMED OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 108,000.

NHTSA ODI 11362268

Jul 14, 2020Speed control

TL* THE CONTACT OWNS A 2020 MERCEDES BENZ C300. THE CONTACT STATED THAT WHILE DRIVING AT A HIGH RATE OF SPEED, THE VEHICLE WOULD ABRUPTLY SLOW DOWN ONCE THE TRAFFIC SIGN READER FEATURE ACTIVATED INDEPENDENTLY WITHOUT WARNING. THE CONTACT STATED THAT ONCE A TRAFFIC SIGN ON THE ROAD WOULD INDICATE A CERTAIN SPEED LIMIT, THE VEHICLE WOULD THE SPEED LIMIT SIGN AND AUTOMATICALLY ADJUST THE VEHICLE'S SPEED TO THE SPEED LIMIT READING. THE CONTACT INITIALLY CALLED MERCEDES-BENZ OF BONITA SPRINGS(14610 TAMIAMI TRAIL N, NAPLES, FL 34110) WHERE HE WAS INFORMED TO CALL THE MANUFACTURER. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE AND THE CONTACT WAS INFORMED THAT THE TRAFFIC SIGN READER FEATURE COULD BE DEACTIVATED ON THE VEHICLE. THE REPRESENTATIVE WALKED THE CONTACT THROUGH THE STEPS TO HAVE THE FEATURE DISABLED. THE CONTACT STATED THAT HE WAS NOT THOROUGHLY MADE AWARE OF HOW THE FEATURE PRIOR TO PURCHASING THE VEHICLE; HE STATED THAT THIS FEATURE COULD LEAD TO A SERIOUS CRASH OR INJURY. THE FAILURE MILEAGE WAS APPROXIMATELY 12,000.

NHTSA ODI 11339325

May 18, 2020Airbags

THERE IS A RECALL ON MY CAR. THE AIRBAGS HAVE NOT BEEN REPLACED YET. THE RECALL WAS ISSUED A LONG TIME AGO. *TR

NHTSA ODI 11325066

← Newer

Working with the data? Download all 45 complaints as CSV · fetched from NHTSA July 14, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2020 Mercedes-benz C-class Cabriolet verdict →