What 584 owners told NHTSA about the 2012 Mercedes-benz C-class Coupe

-The steering wheel and brake locked up and became unusable while driving at approximately 75mph. Cruise control was enabled for a few miles (maybe 2) and disabled after. Around 5 minutes after disabling, the car began to surge between acceleration and deceleration drastically on its own. All of the dashboard lights that come on when the key is initially inserted came on at once while engine was on/running and the car was in drive. After finally being able to reach a safe enough spot, I put the car in park and turned the engine off. I sat for a few minutes to try and turn the engine/car back on and the car would not crank, but the overhead lights, radio, and dash lights were functioning. -This was an extremely dangerous experience. The car began to decelerate rapidly in heavy freeway traffic. At that speed, with many semi-trucks traveling nearby, this sudden loss of speed created an extremely dangerous situation. My vehicle instantly became a slow moving obstacle in the lane. Only by luck and quick reaction was a serious or fatal collision avoided. The car would not start back up so I was sitting at the edge of the highway as many cars flew by just inches away from my car. -I am away at college in a rural city. Accessibility is limited as well as support because of lack of resources. -The car was towed to a mechanic who does not specialize in German cars and stated they did not have the proper tools to "get into the car" because the motor is "locked up" and the car wouldn't crank. -The vehicle will be towed to the nearest dealership (50mi away) who stated they won't be able to look at it for a few weeks from date of arrival. Research indicates this may be linked to a known issue with Electronic Steering Lock (ESL) / Electronic Ignition Switch (EIS) failure in Mercedes vehicles, which can electronically disable the engine and steering. This could've easily been fatal for me and still poses an alarming threat if not addressed.

NHTSA ODI 11687260

The contact owns a 2012 Mercedes-Benz C250. The contact stated while driving 35-40 MPH and depressing the brake pedal, the brake pedal was significantly stiff, and the vehicle failed to respond as needed. The contact stated that upon standing on the brake pedal, the vehicle responded as needed. The contact stated that the failure recurred while driving 65 MPH. The vehicle was taken to the dealer, where the vacuum pump was replaced; however, the failure recurred. The vehicle was taken to Mercedes-Benz of Beaumont (1865 I-10 S, Beaumont, TX 77701), where it was test-driven, and the dealer became aware that the brake pedal was extremely firm. The dealer diagnosed the vehicle and determined that the vacuum pump needed to be replaced. The part was replaced; however, the failure persisted. The contact stated that the failure increased, causing the contact to engage the parking brake to stop the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 96,826.

NHTSA ODI 11670521

Lost of drive power and the vehicle steering wheel locked on my mercedes from a damaged malfunctioning steering lock actuator module due to mechanical issues within the steering column such as bad steering wheel assembly, faulty steering lock module or issue with the wiring or other electrical components and the mercedes dealer is the only one who solves this issue no other mechanic in general. My safety was at risk due to I lost power and lost of front brakes due to bad sway bar assembly or components could of caused and accident when this happened on November 12, 2024 the problem dealership found during vehicle inspection was code 25464 they told me recommend to replace electric lock module and repair estimate was $2,829.78 and before I approved the the amount I told Mr Ivan Velasco service advisor that after they replace the module that if my vehicle was going to be working again and that if I was just going to make 1 payment of $2,829.78 then I would approved it so I did. Weeks later I got an email asking for more money they wanted another payment for $600 saying it needed a sensor that has something to do with the transmission because after replacing the new module the vehicle did not start up there was no type of communications nothing at all and I responded that I was not going to pay $600 more just cause they don't know what their doing because they promise me the car was going to work after they replace the module now that it did not want to crank up they found another issue that's their fault on not doing there job the right way and for telling lies yes their was flashing blue or red icon on my dashboard that look like a car and a lock would go on and off and it displayed a message saying The theft protection is activated. I want to know if I can get this issue approved and to be considered a recall can you please help I'm so frustrating and mad that they want more money when it's already so expensive please help I would of appreciate it thank you.

NHTSA ODI 11638949

The subframe has developed extensive rust and corrosion, which I believe is a result of faulty manufacturing. This corrosion has severely compromised the structural integrity of the subframe, posing a serious safety risk. The corrosion appears to be inherent to the materials or design used in the manufacturing process, leading to the rapid deterioration of the subframe. There are also no warning lights or failure indicators for this issue. As a result, the subframe is at risk of collapsing, which could cause catastrophic failure of the vehicle's suspension and steering systems. This situation creates an immediate danger to both the occupants of the vehicle and others on the road.

NHTSA ODI 11612045

Brake line corrosion

NHTSA ODI 11604605

Took my car for a doorknob repair and was told the whole subframe is rotted. They told me not to drive the car on the highway. The car brakes very hard to the right and always goes right while making cranking noises. Car feels very unsafe. I paid a lot of money for this and own a 2012 c300 4matic.

NHTSA ODI 11592433

This is a low mileage car with odometer reading of 25668 (less than 2000 miles per year), used sparingly and always parked in the garage. On 05/07/2024 I noticed brake fluid flowing from the left rear side of the car; on examination this seemed to come from the flexible hose that connects the brake fluid line to the brake caliper. I called my Mercedes-Benz (MB) dealer and arranged for further inspection and service. The technician identified that the brake fluid lines to the rear were both totally corroded and in need of immediate replacement. Since the lines were embedded behind the subframe it necissated lowering the subframe to access. Other parts were also severely corroded and required replacement. (see attached PDF of Invoice) The total cost of the repair was $4,592.93. The dealership applied a discount of $150.00 to this for an amount due of $4,442.93. As an engineer, I believe the material used for the brake fluid lines were unsuitable and furthermore were unprotected for the harsh environment experienced under the car, and I believe MB with all their experience in automobiles manufacturing over the years clearly should have known and forseen this fact; I do believe that MB is responsible for this premature failure of the brake lines of my car aven driven only 25,666 miles to date. I am therefore requesting NHTSA to require MB to reimburse me for the unnecessary expense of the costly repairs. It is only fortunate that this failure was identified in my garage and not on the highway. Please advise me of your resolution. Thank you.

NHTSA ODI 11589443

While I was driving my 2012 MB C300 4Matic Sport Sedan in Nov', 2023 with history of regular maintenance, noticed a pretty load knocking noise, shudder and drifting to left a bit when it brakes from the driver's rear side especially on the highways. I took it to our local mechanic who was horrified to report that the sub frame was broken and completely rotten out too specifically rust issue with the rear suspension-rear subframe. He gets other German Cars like BMW & Audi even older and more miles in Chicago but none have rusted so much as these MB C-Class cars. Knowing the Dealers wont accept it a manufacturing defect, he was planning to repair it (no chance of wielding that thin metal sheet as the likelihood of breaking it is high). I was surprised to see 2010 Chevy Impala having a much more robust under the cover protection and no rusting with 115k miles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11573402

The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was making a loud bang sound towards the rear of the vehicle while driving over bumps in the roadway. The contact took the vehicle to the dealer and was informed that the rear subframe and the rear brake line were severely rusted. The subframe was replaced under an extended warranty coverage; however, the brake line was not covered under the extended warranty. The brake line was not replaced. The manufacturer was made aware of the failure. The approximate failure mileage was 110,000.

NHTSA ODI 11533167

on 6/20/23 I was driving this vehicle on the 5 freeway north bound exit 102 in Washington. i found myself travelling at 60mph just moving over to the middle lane of traffic. i needed to slow the vehicle a little and pushing down on brakes I found there was no reaction from the braking system. Making a quick decision I moved over to the emergency lane where I came to a stop. There were no warning signs of the issue. I had the vehicle towed to my Mercedes Benz dealership where I had the car service the day before on 6/19/23 where nothing was noted on this problem. After inspection from the technician at the dealership it was found that the brake vacuum pump was no longer working. Which technician said had caused the issue and he had never experienced this issue before. i am bringing this to your attention due to it could have caused a fatal accident to with me and other people on the freeway.

NHTSA ODI 11528248

I found out about the Mercedes Subframe failure issue after having problems on the road, that could have killed me, and being warned not to drive anymore by an authorized repair shop because my vehicle was not safe for me to drive. This has caused many other issues with my cars mechanics due to this defect from the Mercedes factory.

NHTSA ODI 11522182

The contact owns a 2012 Mercedes-Benz C300. The contact stated that while his wife was driving at an undisclosed speed, she heard an abnormal sound coming from the rear of the vehicle. The vehicle was taken to an independent mechanic where it was diagnosed that the subframe wheel assembly needed to be replaced. No warning lights were illuminated. The vehicle was repaired; however, the contact stated that he received an unknown manufacturer’s recall for the subframe assembly which it was then taken to the dealer, and the contact was informed by the technician that the rear brake line was leaking and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and the contact was informed that the VIN was not included in a recall. The failure mileage was approximately 120,000.

NHTSA ODI 11521006

The contact owns a 2012 Mercedes-Benz C300. The contact stated while driving at various speeds, extra brake travel time was needed to stop the vehicle. There was no warning light illuminated. The contact had taken the vehicle to an independent mechanic where the vehicle was purchased, and he was informed that the failure was caused by the new brake pads placed on the vehicle. The contact eventually took the vehicle to a dealer and was informed that the fuel tank and brake lines were corroded; and the contact was provided an estimate for the repair. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 96,000.

NHTSA ODI 11518035

The left rear weld of the subframe on my 2012 C300 4matic has rotted through and appears to be a manufacture's part defect. I found out about this issue from a brake inspection and told it is a safety concern, which Mercedes Benzes is aware of but has no recalls for the defect.

NHTSA ODI 11513818

The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was taken to the dealer for an airbag inspection. During the inspection, the dealer informed the contact that the rear subframe was corroded. The vehicle was diagnosed and the contact was informed that the brake lines and rear subframe needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 120,000.

NHTSA ODI 11477748

From the mechanics notes: Four-wheel alignment could not be completed. Attempts to align the rear axle were unsuccessful due to flexing/movement in the rear suspension. A brief road test revealed occasional suspension “clunking” coming from the rear of the vehicle. Close examination of every suspension component mount revealed heavy cracking on the passenger side lower drag link subframe mount (see emailed image). The driver’s side low drag link mount location is also starting to show signs of overstress and rust/flaking. This is a known design defect that has been the subject of a manufacturer’s recall in Canada. Given the substantial safety impact of this design defect/failure, it is expected that a US recall will be forthcoming. Proper repair of this failure involves removing the entire rear axle/subframe assembly and either rebuilding/re enforcing the subframe or replacing it with a new unit and transferring all the suspension components to the new subframe. A current check of subframe availability is showing NLA (no longer available) status from Mercedes wholesale dealers – likely due to recent high demand and inability to satisfy that demand. This supply issue may also be playing a role in Mercedes’ failure to address this high level safety issue with a US based recall campaign. The manufacturer may be ramping up production of this component to address anticipated need – waiting to announce a recall when it has sufficient parts on hand to execute the campaign. It is strongly recommended that you file an NHTSA complaint for this issue and limit driving until the problem is rectified either independently or under the auspices of a recall campaign. The passenger side rear drag link has not yet completely separated from the subframe but is likely to do so soon which can result in an accident or loss of control as this critical suspension link is responsible for maintaining steering direction of the right rear wheel.

NHTSA ODI 11458128

The rear drivers side had a loud chunking/clanking noise while driving and the vehicle was unable to control and break when in motion. Driving was impossible as the breaking component was a total failure and car could not be controlled while traveling down 45-50mph zone. I reduced my speed to 20-25 mph by letting off on the gas to get better control of the car if breaking would need to be suddenly made. I relied on the shoulder to pull off if any sudden breaking was needed. The car was immediately take to be reviewed by a specialized Mercedes benz mechanic and further inspection proved that the rear subframe on the driver’s (left) side was corroded and broken. The connecting arms are rusted, corroded and rendered the car inoperative. I notified my insurance company as well as car manufacturers corporate office. I researched this issue further and discovered that this reoccurring issue with this make and model. There are a pheletera of recounting of this same issue on various message boards to validate the same issues and callouts I found. The car was taken to the dealership that it was purchased and further inspection showed that the left side subframe/ subframe arms were corroded with rust and broken. The brake lines and fuel tank were equally rusted and corroded. The service manager confirmed that this is defect of the car but it had been part of a recall. I had the car towed for 2nd opinion to another dealership service department to access the car and this callout further validated the corrosion and rust was wide spread and has rendered the car inoperable unless these damages were fixed.

NHTSA ODI 11435789

Brakes failed to deploy, randomly, during recent trip; VERY DANGEROUS; pressed brakes, would NOT engage and car kept moving and would not stop; pushed car into P (Park) to stop moving; just completed a 225 mi trip from Chicago to Detroit Metro area traveling at speeds between 65-70 mph with no issue, all service on vehicle is and has been conducted via Mercedes authorized dealers, had vehicle in for service on morning of trip for overview and safety check prior to leaving and no known issues; after coming off freeway engaged brakes upon pulling into neighborhood and vehicle brakes failed completely-stopped engaging; NO NOTIFICATION; NO INDICATOR LIGHTS OR READ OUT OF ISSUES related to brakes was indicated on dashboard; had we been on the freeway at the time of incident coming off an exit ramp at high speed we would have suffered a grave result, brakes failed completely. THIS IS A DANGER and UNACCEPTABLE for this manufacturer; vehicle has been towed to dealership, is not drivable, and is currently being assessed. This has been widely reported on other sites, regarding this specific vehicle, Mercedes C250, my model year is 2012; I researched this issue, yesterday, to determine what could possibly have gone wrong as vehicle was not leaking fluids and NO indication of issues during recent diagnostics and safety check two days prior. Not having sufficient braking capability with NO warning or indication is DANGEROUS, a liability to manufacturer and should be investigated immediately. Thank you.

NHTSA ODI 11425478

AT ABOUT 40,000 MILES THE PARKING BRAKE BEGAN STICKING AND WAS DIFFICULT TO RELEASE. THIS WAS REPLACED UNDER WARRANTY. IT BEGAN HAPPENING AGAIN . I SPOKE TO THE MERCEDES USA AND THEY SAID I WOULD HAVE O PAY TO REPLACE IT. I BELIEVE THIS PART IS DEFECTIVE.

NHTSA ODI 11384474

I WAS DRIVING ON THE HIGHWAY AT ABOUT 60MPH IN THE LEFT HAND LANE. I WAS ABOUT 7 CAR LENGTHS FROM THE CAR IN FRONT OF ME AS I HAD JUST MOVED INTO THAT LANE TO MOVE TO THE RAMP TO MOVE OFF THE HIGHWAY. THE VEHICLE IN FRONT OF ME BRAKED, AND WAS GOING AT A LOWER SPEED. I TRIED TO SLOW DOWN AND MY CAR DID NOT SLOW. I PRESSED MY BRAKE TO THE FLOOR AND MY CAR STILL WOULD NOT STOP. I WAS ABLE TO PULL TO THE SHOULDER AND THE CAR FINALLY CAME TO A STOP CLOSE TO THE RAMP, I THOUGHT IT WAS AN ISOLATED INCIDENT EXCEPT I SAW ON A WEBSITE, OTHERS HAD THE SAME PROBLEM.

NHTSA ODI 11145223

MY VEHICLE WAS DAMAGED BY K AND H AUTO. THE ELECTRICAL UNIT IS MALFUNCTIONING, THE LIGHT IS BROKEN ON THE RIGHT SIDE, AND THE ROTORS AND BRAKES HAVE BEEN RUSTED, PLEASE HAVE SOMEONE ATTEND TO THIS MATTER. THANKS, AND HAVE A VERY BLESSED DAY. ANOTHER COMPANY BY THE NAME OF ANS TOWING, TOWED MY VEHICLE WITHOUT CARE AND I AM NOW HAVING ACCELERATION ISSUES WITH MY VEHICLE. THE VEHICLE WAS DRAGGED THROUGH WATER ON OCTOBER 17-18, 2018.

NHTSA ODI 11066436

2012 MERCEDS BENZ C63 AMG. CONSUMER WRITES IN REGARDS TO MERCEDES BENZ DEALER NOT REPLACING OR REPAIRING ANY DEFECTIVE VEHICLES PARTS. *LD THE CONSUMER STATED THE CLEAR COAT PAINT WAS PEELING OFF OF THE BRAKE CALIPERS.*JS

NHTSA ODI 11042428

TAKATA RECALL, NOT ACTION TAKEN IN A EFICCIENT TIME BRAKES 2017 ELEC STABILITY CONTROL 2013 AND 2017

NHTSA ODI 11048515

BRAKE FAILURE. DRIVING VEHICLE ON HIGHWAY WITH A 75 MPH SPEED LIMIT. WHEN I ATTEMPTED TO BRAKE VEHICLE, I FOUND I DID NOT HAVE ANY POWER BRAKES. BRAKE PEDAL WAS HARD. PRESSING THE BRAKE PEDAL AS HARD AS I COULD DID NOT DO ANYTHING TO SLOW DOWN MY VEHICLE. I DID NOT HAVE ANY ABILITY TO SLOW DOWN VEHICLE. TO AVOID A COLLISION, I PUT THE VEHICLE IN NEUTRAL, AND DOWN SHIFTED GEARS. NO ALARMS, OR VISUAL INDICATORS CAME ON TO INDICATE A PROBLEM EXISTED. CAR TOWED TO THE MERCEDES BENZ AUTHORIZED DEALERSHIP I HAVE ALWAYS HAD MY CAR SERVICED AT. BRAKE BOX SITTING BEHIND THE MOTOR HAD BROKE. NO SENSIRS OR FAULT US ASSOCIATED WITH THE BRAKE BOX. VISUAL CHECK OF THE BRAKE BOX IS. IT ON ANY MAINTENANCE CHECKLIST.

NHTSA ODI 10983783

TL* THE CONTACT OWNS A 2012 MERCEDES BENZ C250. THE CONTACT STATED THAT WHILE DRIVING 65 MPH, HE ATTEMPTED TO ENGAGE THE BRAKES BUT IT FAILED TO STOP THE VEHICLE. THE VEHICLE WAS TAKEN TO THE DEALER WHERE THE TECHNICIAN DIAGNOSED THAT THE BRAKE VACUUM WAS DEFECTIVE AND NEEDED TO BE REPLACED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 25,000 AND THE CURRENT MILEAGE WAS 30,000.

NHTSA ODI 10542718