2019 Mercedes-Benz C 300 Owner Complaints

The factory infotainment system (Mercedes NTG 5.5 head unit) displays Android Auto incorrectly. Instead of using the full width of the center display, Android Auto is cropped into a reduced window on the right side of the screen. The remaining roughly one-third of the screen shows a static logo with no function. Apple CarPlay on the same head unit and screen displays correctly at full width. This indicates a software or integration defect specific to Android Auto, not a hardware or display failure. Safety risk: Because navigation is pushed to the far right edge of the display and shrunk, the driver has to turn their head and eyes further from the road, and for longer, to read the map, turn-by-turn directions and incoming call information. Smaller map content takes more time to interpret, which lengthens each glance away from the road. This increases driver distraction during normal driving, especially in complex traffic and at intersections where navigation matters most. The problem is constant and reproducible every time Android Auto connects. It persists across different phones, cables and phone settings. The manufacturer's customer support was contacted. They offered no fix and directed me to pay for a dealer diagnosis. The problem has not been confirmed by a dealer or independent service center: UNKNOWN. No warning lamps or messages are associated with it. The vehicle is available for inspection tested on multiple new phones, many existing forums share the same issue. Anroid auto has taken responsibility but the Mercedes team has to fix this

NHTSA ID

11766218

Incident

Sep 22, 2026

The M264 2.0L engine suffered a catastrophic internal failure. While making a left turn at an intersection, the vehicle suddenly shut off and stalled, leaving the car stranded in active traffic and creating an immediate safety risk. Prior to the shutdown, the check engine light came on accompanied by severe shaking and misfires. The vehicle was inspected by an authorized dealership service center, which confirmed complete engine failure. Mercedes-Benz issued a 15-year/150,000-mile extended warranty for the M264 exhaust valve and cylinder head assembly, but warranty coverage was refused because the cylinder defect progressed to total engine destruction. The vehicle remains available for inspection upon request.

NHTSA ID

11766013

Incident

Sep 23, 2025

The vehicle experienced a severe safety issue involving a sudden loss of motive power in active traffic. 1. Initial Symptoms & Diagnosis: Recently, the Check Engine Light illuminated. Although the light turned off before my scheduled appointment, I still brought the vehicle to an authorized Mercedes-Benz dealership for a safety inspection. 2. Dealer Confirmation: The dealership inspected the vehicle and diagnosed an internal electrical fault with the engine oil control valve and harness. They recommended replacing the parts. Because the vehicle seemed to be running fine and the dealer did not warn me that it was unsafe to drive, I drove the vehicle home to consider the repair. 3. Critical Safety Incident: Shortly after bringing the car home, I was stopped at an intersection. When I attempted to accelerate, the vehicle suddenly entered "limp mode." It lost almost all motive power and would only crawl forward at a very low speed. This sudden loss of acceleration in the middle of traffic put me at an immediate risk of a collision. I had to pull over to the side of the road and restart the engine to regain normal function. 4. Prior Symptom: Looking back, I experienced a similar brief loss of power approximately one year ago. However, the vehicle recovered quickly after I restarted the engine, and no warning lights came on, so I was unaware of the severity of the defect at the time. The vehicle has less than 20,000 miles. An internal engine valve failure causing a sudden loss of acceleration on public roads is a major safety defect. The vehicle is currently parked for safety reasons and is available for inspection upon request.

NHTSA ID

11764481

Incident

Sep 5, 2026

Shifting gears when stopped and the car lunged forward while I was stopped at a red light. I almost hit the car in front of me at the red light. Very rough gear changes and changing out of the correct gear to the wrong one and then back into another one. Severe speed changes - jerking the car back or it lunges forward, while driving results in loss of reasonable control of the vehicle and inability to to shift correctly out of traffic. Mercedes benz has a technical service bulletin on this problem and is aware that the 9G-Tronic - internally designated as the 725 transmission (fault code P07B700) is defective and known to experience sudden pressure sensor failures or valve body faults within the transmission control unit which prevents the car from shifting gears corrected or forces limp mode. The repair is a minimum of $5,200. MBZ has known this is a defect and wide spread issue but unwilling to contribute to the repair or recall or respond to my letters and the inquiries of other vehicle owners I have spoken to that have the same issues. It is a catastrophic mechanical failure from a sensor they know is bad and is occurring shortly after warranties are expiring. It is putting all of our lives and the lives of others at risk of an accident due to the failure of their part. Thank you for your consideration.

NHTSA ID

11757307

Incident

Mar 6, 2026

Throttle body and accelerator pedal position sensors failed. Component is available for inspection upon request. Independent service center confirmed failure on 1/3/2026 with 6 stored fault codes: P2101, P0122, P0222, P0123, P0223, P2135. Vehicle shuts off while driving without warning at various speeds. Loss of power steering and power brakes occurs when engine stalls, creating immediate risk of crash, injury or death to occupants and other drivers. Manufacturer customer service confirmed in writing 4 times that engine shutting off while driving is a safety issue and that these exact codes match Service Campaign 2022090005. On 1/7/2026, manufacturer denied campaign applies to this vehicle and refused no-charge dealer inspection, demanding customer pay diagnostic fees to confirm defect they already documented. Vehicle has not been inspected by manufacturer or dealer because manufacturer refuses free inspection. Check engine light illuminated prior to stall events. Manufacturer has actual knowledge of safety defect under 49 U.S.C. 30118 and is creating financial barrier to repair of defect covered by their own service campaign. Request NHTSA investigation and order manufacturer to repair under Service Campaign 2022090005 at no charge.

NHTSA ID

11747712

Incident

Jun 23, 2026

My 2019 Mercedes-Benz C300 Coupe’s front driver seat belt will not fully retract to its stowed position. This creates THREE safety hazards: 1.Passenger Trip Hazard: The extended belt causes difficulty when exiting from the rear seat — passengers can easily trip over the non-retracting belt 2.Door Damage Risk: Belt gets stuck in the door, preventing proper closure and potentially damaging the door or wearing down the seat belt webbing 3.Safety System Failure: A belt that doesn’t retract properly may not fully restrain occupants in a crash, compromising the seat belt safety system Dealer Response: My dealership told me this is “out of pocket” repair cost, even though the identical retraction issue exists in 2017–2021 C-Class Cabriolet (A205 platform) vehicles that ARE covered under Safety Recall 21V-032000. Mercedes fixed this with damping foam adjustment in the recalled Cabriolets but is refusing the same repair on C300 Coupes. Defect Pattern: This is the same design flaw in the front seat belt retractor geometry that caused the recall. The distance between the retractor and damping foam within the B-pillar doesn’t meet production specifications. Safety Risk: If occupants find the belt inconvenient due to poor retraction, they may not wear it — increasing crash injury risk. No advance warning of retractor failure exists. Request: NHTSA should investigate whether the C300 Coupe should be included in this recall or if a separate recall is needed for the same defect. Vehicle Info: 2019 Mercedes-Benz C300 Coupe

NHTSA ID

11742426

Incident

Jun 1, 2026

Upon starting engine while parked the engine vibrated roughly then stopped. Engine light and coolant light illuminated but shut off. Vehicle proceeded as normal, however, as I proceeded for the highway about 1 - 1/2 blocks and approximately 1,200 feet before approaching highway the vehicle 1200 abruptly lost acceleration; engine light and coolant light illuminated again, then engine abruptly shut down in the middle of the road causing a severe safety hazard. Putting myself and others at risk. There were no symptoms of the problems prior to the failure. Coolant leakage; sluggish engine/acceleration; jerking acceleration; coolant light illumination steady.

NHTSA ID

11738906

Incident

Dec 28, 2025

The contact owns a 2019 Mercedes-Benz C300. The contact stated that while driving and attempting to close the sunroof, the sunroof made an abnormal popping sound. The contact pulled over and attempted to close the sunroof, but the sunroof failed to close. The contact related the failure to NHTSA Campaign Number: 21V197000 (Structure); however, the VIN was not associated with the recall. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not contacted. The failure mileage was approximately 53,000.

NHTSA ID

11729410

Incident

Apr 5, 2026

Mileage

53,000 mi

Odometer Fraud. The contact purchased a 2019 Mercedes-Benz C300. The contact stated that after purchasing the vehicle, it was discovered that there was a mileage discrepancy. The vehicle was a dealer sale. The contact stated that at the time of purchase, the odometer reading was approximately 54,000 miles. At the time of registration, the mileage was approximately 54,000 miles, and the same mileage was also reflected on the Carfax report. The contact stated that the mileage discrepancy was later discovered through a public report with the Federal Trade Commission (FTC); however, the mileage was not provided. The contact stated that the mileage discrepancy occurred after two OTA’s were performed on the vehicle. The contact stated that during the OTA’s on the vehicle, the mileage was changed. The contact stated that several documents with the mileage discrepancies were listed with the FTC. The contact also reported the discrepancy to the Department of Motor Vehicles.

NHTSA ID

11716768

Incident

Feb 9, 2026

Mileage

54,000 mi

While driving on highway, the engine light came on, a diagnostic test was performed by dealer, oil control valve defected) This could cause engine to lock up while driving, a serious safety concern. I contacted Mercedes Benz corporate office seeking help, because of factory defect. They're not assisting me with this extreme safety matter!!

NHTSA ID

11712677

Incident

Dec 21, 2025

While driving at approximately 65 mph on the I-405 freeway in Irvine, CA during rainy conditions, my 2019 Mercedes-Benz C300 suddenly and completely lost acceleration without warning. At the same moment, a Check Engine Light illuminated on the dash. I was forced to coast across all lanes and stop in the emergency shoulder in a very unsafe area with high-speed traffic passing close by in low visibility rainy conditions. Multiple vehicles nearly struck us, including one that had to emergency brake directly behind my car in the shoulder. I contacted AAA and the vehicle had to be towed because it was not safe or driveable. My girlfriend was also in the car and both of us experienced significant fear and distress during and after the incident. My mechanic retrieved fault code P019185 and stated this is a known software problem with the engine control unit that requires a Mercedes software update and reset of mixture adaptations per a manufacturer LI/service document. This means the manufacturer appears aware of the defect and the required software fix, yet I received no recall notice or safety warning. A sudden total loss of engine power at highway speeds creates an extreme crash risk and life-threatening danger to the driver, passengers, and surrounding traffic. There have been other serious drivability issues with this vehicle in the past (misfires, coolant pipe failure, etc.), but this incident was the most dangerous. I am reporting this because this defect appears safety-related and could easily cause a fatality if it happens to someone else at freeway speeds. Diagnostic Note from official Mercedes-Benz Fletcher Jones of Newport Beach Mechanic: “FAULT CODE P019185, WILL START WITH PERFORMING THE SOFTWARE UPDATE OF ME CONTROL UNIT, RESET THE MIXTURE ADAPTIONS PER LI DOCUMENT AND RECHECK.” Tow Provider: AAA — tow confirmation available if needed.

NHTSA ID

11708992

Incident

Jan 3, 2026

This vehicle was brought to an authorized Mercedes-Benz dealership for regularly scheduled maintenance. Shortly after this service, the vehicle began experiencing significant issues including difficulty accelerating, engine hesitation while driving, and noticeable shaking at idle. This car has never overheated. The vehicle was returned to the dealership for inspection. The dealership diagnosed a cracked cylinder head and advised that the repair requires replacement of the cylinder head at an estimated cost of approximately $11,000. The failed component is available for inspection and the vehicle is currently at the dealership. The vehicle has approximately 46,000 miles, has been regularly maintained, garaged, and driven under normal conditions. These symptoms created engine performance issues that could result in loss of power or inability to accelerate while driving, creating a potential safety risk, especially in traffic or at highway speeds. I regularly transport my young grandchild in this vehicle. The possibility of sudden engine failure, loss of power, or breakdown while driving raises significant safety concerns for myself and any passengers, particularly a young child. The failure has been confirmed by an authorized Mercedes-Benz service center. During my own research, I discovered there have been recalls involving similar engines for the same model year, as well as multiple owner complaints reporting similar engine or cylinder head failures on this vehicle. I contacted Mercedes-Benz customer care on December 17, 2025, after receiving the dealership diagnosis, and was advised that I would receive a response within 72 hours. As of today, I have not received any response. I attempted to call customer care again, but the phone system would not accept a voicemail and no representative answered. My case number with Mercedes-Benz is 19653254. No prior abuse, misuse, or abnormal driving conditions occurred. The vehicle was properly maintained.

NHTSA ID

11706568

Incident

Dec 8, 2025

The contact owns a 2019 Mercedes-Benz C300. The contact stated that the convertible top support were fraying. The contact stated the parts were almost the thickness of a shoelace and enabled the convertible top to fold correctly when the top was folding down. The contact stated that the Part Number was A2057780500. The contact had taken the vehicle to a local dealer, where it was diagnosed, and the dealer determined that the entire convertible top needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure, and the contact filed a case. The failure mileage was approximately 43,000.

NHTSA ID

11704696

Incident

May 12, 2025

Mileage

43,000 mi

I think the recall is on communication software. I contacted Mercedes Benz many times in the past 2 years. Mercedes Benz asked its dealer to do the recall but dealer said they cannot do it. Mecedes Benz also said their software supplier had not found a solution yet.

NHTSA ID

11698435

Incident

Jul 1, 2022

I was driving on the hwy 94 in Minneapolis and I had the cap to my sunroof fly off on the freeway. There’s a recall out on the sale vehicle but 4matic but not on my vin number. This is a huge safety issue and it’s been happening to quite a few people I know. No one was injured and it didn’t cause damage to any other vehicle but when I brought it into the shop they said the recall that was on this part was not for my exact vehicle.

NHTSA ID

11691716

Incident

Aug 31, 2025

I am writing to formally report an ongoing issue and safety concern with my vehicle. Since the day I purchased the car, I have experienced numerous mechanical problems and have spent a significant amount of money on repairs. In August, I had to take my vehicle to a local repair shop three times due to persistent issues. The car was also towed by AAA three separate times for safety reasons. My main concern is that the vehicle hesitates during acceleration and feels sluggish while driving, which creates a serious safety risk on the road. I contacted Mercedes-Benz and filed a claim regarding this issue; however, I have not received any meaningful assistance or resolution. I am requesting that this matter be re-evaluated and properly addressed as soon as possible, as my safety and the reliability of the vehicle are at risk. Please confirm receipt of this message and advise me on the next steps or any documentation needed to proceed with my claim. Thank you for your prompt attention to this matter. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11691362

Incident

Aug 11, 2025

The contact owns a 2019 Mercedes-Benz C300. The contact stated that while driving at various speeds, the vehicle suddenly lost motive power and decelerated. The accelerator pedal was depressed while attempting to accelerate. The contact stated that the fuel gauge failed to accurately display the level of fuel in the tank. The check engine warning light was intermittently illuminated. The vehicle was taken to the dealer, who diagnosed that the fuel level sensors had failed. The fuel tank and fuel pump needed to be replaced. The vehicle was not repaired. The contact became aware of NHTSA Campaign Numbers: 23V880000 (Fuel System, Gasoline), and 23V445000 (Fuel System, Gasoline); however, the model year was not included. The manufacturer was informed of the failure. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 157,000.

NHTSA ID

11688189

Incident

Aug 28, 2025

Mileage

157,000 mi

Started car, put in reverse, reverse camera did not engage, screen blacked out, I restarted car thinking systems and computers needed a re-boot. The backup camera no longer works. Coincidently, in reading the recall of the back-up camera on the 2019 C 300 Mercedes, this fits and checks all the boxes. I would like to get this fixed asap, my car has $63,000 miles, and no backup camera. The safety of this feature is remarkable, and cannot express how often I used it, I can see many things that I cannot see now. This problem has been confirmed by my mechanic. The dealership and MB USA has referred me here. The screen black out was the first and only warning I received before no longer able to engage camera, this happened in late Winter 2025. I am shocked that my VIN is not a part of the recall. Please add this so that I am able to use my back-up camera. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11683456

Incident

Feb 1, 2025

The contact's husband owns a 2019 Mercedes-Benz C300. The contact stated that the front driver's side and passenger's side seat belts failed to retract as designed. The vehicle was taken to the dealer, where it was determined that the seat belt assemblies needed to be replaced. The dealer informed the contact that the VIN was not included in NHTSA Campaign Number: 21V032000 (Seat Belts). The contact was provided with an estimate for the repair. The vehicle was not repaired due to the cost. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was unknown.

NHTSA ID

11681509

Incident

Aug 19, 2022

Engine stuttered violently while driving 40mph. Check engine light was coming on and off. I immediately pulled to the roadside for my safety. I put the vehicle in park and cycled the ignition and the problem disappeared. the vehicle stuttered twice a few miles as I was taking the vehicle to the garage. I haven't had it serviced yet. The vehicle was serviced in the past for a Recall that had similar issues.

NHTSA ID

11676589

Incident

Jul 26, 2025

I had a A1 service completed on 5.23.25 with Mercedes Benz dealership in Sourh San Francisco. 2233 Gellert Blvd. On [XXX] 48 hrs later as I was leaving working- 4-5 blocks before entering the freeway, my car suddenly struggled to drive over 20MPH and the check engine light came on. I pulled over a block before entering freeway. I had it towed and got a Lyft’ ride home. It was a holiday weekend and I had to rent a car . Vehicle accessed 2 days later . I was told it needed a software update and there was a bulletin that came out in 2024 recommending to have the update and I needed to pay to have it repaired by performing a hard/soft upgrade . No empathy was evident . I said I knew nothing about it - dealership said they weren’t obligated to advise. I could have been in a collision or caused and accident and seriously injured had it occured while on freeway . This should be a recall as my life was at risk and so are others driving this year, make and model. The Mercedes Rep. told me she tested the car and was surprised by how it struggled to get past 20 mph, she thought maybe the mechanic had made an error a few days before. I feel very lucky I wasn’t in an accident- or a worst seriously injured! This bulletin warning should be a recall and looked into for a future recall that could save life’s. Knowing, this is a risk for a possible accident , it’s unacceptable that it is only a bulletin and not mandatory to share with owners of the this car. This was very scary and stressful situation. I was stuck in an area in Oakland, Ca known for high crime. In the end Mercedes waived the repair fee, they said under the circumstances and how my life was put as risk . I still think perhaps a wire or something may been disconnected- but no one will admit. Hence they waived fee. Please investigate , I look forward to your findings. Respectfully, [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11664002

Incident

May 25, 2025

The contact owns a 2019 Mercedes-Benz C300. The contact stated that while at a stoplight, there was an abnormal odor of fuel inside the vehicle. The contact stated that the vehicle failed to respond as needed. The vehicle was restarted and shut off independently. The check engine warning light was illuminated. The contact stated that the failure was related to NHTSA Campaign Number: 21V961000 (Fuel System, Gasoline). The vehicle was towed to an independent mechanic who determined that the failure was a fuel rail failure. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted and confirmed there were no open recalls on the VIN. The failure mileage was approximately 60,000.

NHTSA ID

11656739

Incident

Apr 19, 2025

Mileage

60,000 mi

Po52E71- Emissions issue with crankcase. Mercedes implemented an extended warranty on various models but excluded 2019 C300, which definitely has the same issues. See below in reference to previous models. IMPORTANT EMISSION EXTENDED WARRANTY INFORMATION In our continuing efforts to assure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA, LLC (“MBUSA”) is extending the warranty coverage on the intake line assembly in certain Model Year (“MY”) vehicles listed below from the original New Vehicle Limited Warranty of 4 years/50,000 miles to 15 years/150,000 miles (whichever occurs first) due to the following condition: • Under certain circumstances, the partial-load ventilation valve (a part of the intake line assembly) may not work as intended, resulting in the illumination of the check engine Malfunction Indicator Lamp (‘MIL’). A faulty partial-load ventilation valve might also increase exhaust gas emission. Model Model Years Sales Designation C-Class 2015 – 2018 C 300, C 300 4MATIC C-Class Convertible 2017 – 2018 C 300 Convertible, C 300 4MATIC Convertible C-Class Coupe 2017 – 2018 C 300 Coupe, C 300 4MATIC Coupe C-Class Hybrid 2016 – 2018 C 350e E-Class 2017 – 2019 E 300, E 300 4MATIC GLC 2016 – 2019 GLC 300, GLC 300 4MATIC GLC Coupe 2017 – 2019 GLC 300 4MATIC Coupe GLC Hybrid 2018 – 2020 GLC 350e 4MATIC SLC 2017 – 2020 SLC 300 SLK 2016 SLK 300

NHTSA ID

11648766

Incident

Jan 23, 2025

The contact owns a 2019 Mercedes-Benz C 300. The contact stated that while driving 65 MPH, the vehicle inadvertently lost motive power, and was unable to accelerate above 25 MPH. The check engine warning light was illuminated. The vehicle was taken to the dealer, who determined that the PCM required a software update. The vehicle was repaired. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The failure mileage was 36,000.

NHTSA ID

11637804

Incident

Jan 22, 2025

Mileage

36,000 mi

Leaking fuel as described in one of the previous recalls for the car. There is a fire hazard but the VIN is not listed as being eligible.

NHTSA ID

11633699

Incident

Dec 20, 2024