2019 Mercedes-Benz C 300

On January 8, 2021, after ongoing review with Mercedes Benz, the National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation (ODI) opened PE21-001 to assess allegations of front roof panel detachments while driving at highway speeds in certain 2015 Mercedes-Benz (Mercedes) C-Class vehicles.The subject front roof panel is a stationary panel composed of polycarbonate and is attached to the vehicle via adhesive at the time of manufacture. The panel is found on subject vehicles equipped with panoramic sunroofs. Over time, the subject panels may exhibit cosmetic degradation leading to replacement of the panel, a procedure which entails: removal of the old panel and adhesive, site preparation, and installation of a replacement panel with new adhesive.The consumer complaints that prompted the opening of PE21-001 all described detachments of front roof panels that had been replaced after the vehicle was put into service.Mercedes' internal investigation identified a broader scope of affected vehicles (2014-2020 CLA, GLA, C, S, GLC, and GLE class) and found the following potential service procedure- related causes of front roof panel detachments:- Improper surface pretreatments such as the use of the wrong primer or cleaner or scoring of the surface; or - Use of the incorrect adhesive.These conditions lead to a front roof panel bond that, even if sound at the time of repair, cannot maintain its strength over time and environmental exposure.Mercedes updated its service and parts ordering systems to reinforce the proper use of specified kits and procedures via webinars, shop foreman meetings, and explicit reference to the risks incurred by diverging from the repair procedures. Mercedes is also furnishing parts ordering assistance, and will hold dealerships accountable for improper repairs.ODI's analysis of the ten complaints it has received from the public (VOQ's) and MBUSA's complaint data submitted in response to the information request letter for PE21-001 identified a total of 57 non-duplicative reports alleging incidents in which the front roof panel detached from the vehicle while in motion. Included within the 57 reports are incidents where consumers state the panel detached ...and flew off into traffic.On March 19, 2021, Mercedes notified NHTSA that it would recall subject vehicles with front roof panels known to have been replaced after the original sale of the vehicle. In total, the recall (designated as Recall 21V197) covers 15,099 vehicles that were ever registered in the United States. Based on Recall 21V197 and the remedy implemented by Mercedes, further investigation does not appear to be warranted at this time.Accordingly, this investigation is closed.The ODI complaints cited above can be viewed at www.nhtsa.gov under the following ODI identification numbers: 11376425, 11352686, 11351629, 11349158, 11341541, 11337594, 11324100, 11311591, 11222127, 11404183

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

Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or control the vehicle. Cause Ball screw drive (KGT) of electric steering damaged by: 1. External force due to: ‑ Hitting the curb/posts with the front wheels. ‑ Driving over obstacles (e.g. pothole/ threshold/ speed bump/ gully) at an inappropriate speed. 2. Corrosion/ water ingress through a damaged boot (see attachment). ‑ Cracks (1) ‑ High pressure cleaner (2) ‑ Animal bite (3) See various examples listed in the attachments for examples of outside influence. Remedy Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Replace electric steering. Note: Steering gears replaced due to outside influence or damage must not be claimed under warranty!

Complaint • Harsh 1‑2, 2‑3, and/or 3‑4 shift • Jerky shifting • Jolting when accelerating from stop Cause Insufficient software application causing elevated K81/K27/B05 fill time adaptations and elevated torque adaptations for concerning shift. Note: Shift quality in E Performance models can be affected if the HV Battery state of charge (SOC) reaches 25% or below. Remedy Check VGS software level, and follow relevant remedy instructions. (see attachment) AMG 43 models with VGS software levels up to 22A: As of 4/18/2025, an aftersales software improvement has been released. This software has been implemented in production as of model year 2024, however this LI should still be followed if the concern is present. 232 ‑ A0009025699 206 ‑ A0009025599 Please ensure your Xentry machine is up to date with the latest Add Ons and continue with the following steps: Note: ALL steps must be performed to rectify concern 1. Perform software update all control units included in VGS software update. 2. Check transmission oil level and correct, if necessary (transmission oil temperature > 60 °C) 3. Perform Xentry Valve Flushing procedure at least 3x 4. Perform resetting of deceleration values (VGS > Special Procedures > Special procedure > Resetting learned values Deceleration mode) 5. Perform a standstill adaptation, then read out new EEPROM data 6. Perform driving adaptation(s) while adhering to the below parameters for at least 20‑30 miles. Note: There is no menu in Xentry for this procedure. We recommend displaying the torque in the instrument cluster. If all below parameters are met at the time the shift, a driving adaptation will automatically occur. Harsh 1‑2 Perform a driving adaptation of 4‑5 (adapts K81 for the 1‑2 shift) Harsh 2‑3 Perform a driving adaptation of 6‑7 (adapts B05 for the 2‑3 shift) Harsh 3‑4 Perform a driving adaptation of 3‑4 (adapts K27 directly) ‑ See attached PDF for min/max torque, and RPM parameters ‑ Transmission oil temperature > 30°C (>86°F) ‑ Level track (no incline/decline) ‑ Slippery drive program ‑ Display the torque in the instrument cluster ‑ Constant engine torque ‑ Do not shift via paddle AMG 63 models with VGS software levels up to 22A: No aftersales software resolution is planned. Perform above steps and release the vehicle. If the vehicle returns and already had ALL steps in this LI performed on a previous visit, or has software level 23A and newer: Please submit a TIPS case to the Powertrain inbox and ensure the following is included: ‑ Initial Quick Test w/ Freeze Frame Data ‑ VGS Control Unit Log ‑ Initial EEPROM (before any adaptations or Xentry procedures were performed) ‑ Detailed vehicle history of the complaint

Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket, handbag etc. Remedy As of the 6th generation, the vehicle key can be recoded so that the tailgate no longer opens as a result of a long press on the button, but by double‑clicking on the button instead. This reduces the likelihood of the button being activated accidentally or unintentionally. The recoding can be carried out as follows: 1. Add SA Code O19 into VeDoc (O for Oscar, not "zero") • an XSS ticket may be necessary to add the SA code 2. Perform SCN coding of EIS N73 control unit 3. Deactivate the vehicle key (a successful deactivation is indicated by the LED lighting up 2x briefly and then 1x for a long period). 4. Place the vehicle key in the storage compartment on the key symbol and turn on the ignition. IMPORTANT: all other vehicle keys must be outside the recognition range of the vehicle when doing this! Perform steps 3 and 4 successively for all vehicle keys. Notes: 6th, 7th and 8th generation keys can be deactivated as follows: Up to modification year 22/1 by double clicking the "Lock button" As of modification year 22/1, by press and holding the “Lock button", then double‑click the “Unlock button" at the same time. On model series 167, the storage compartment with the key symbol is located in the armrest. The SCN coding from the EZS is only transferred correctly to the vehicle key under the following conditions: Only one vehicle key is located in the vehicle, this key has been deactivated and it is positioned on the marking in the storage compartment for the data transfer. The costs for this adaptation are to be borne by the customer. For the newer BR 174, 178, 244, 248, 520, and 540, a software update must be initiated, as there is no way to perform SCN coding.

Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA is extending the warranty coverage for the Diagnostic Module for Tank Leakage Detection ("DMTL") on your vehicle from the original New Vehicle Limited Warranty of 4 years / 50,000 miles to 15 years/150,000 miles (whichever occurs first). This applies to the vehicle regardless of ownership. Why the Warranty extension? On certain Model Year 2018 - 2024 A / C / CLA / CLS / E / G / GLA / GLB / GLC / GLE / GLS / GT / S / SL Mercedes-Benz vehicles, under certain circumstances, the DMTL may trigger erroneous Diagnostic Trouble Code ("DTC") entries that may result in the illumination of the Check Engine Malfunction Indicator Lamp ("MIL"). Any repairs under this warranty extension must be performed by an authorized Mercedes-Benz dealership. • If your preferred authorized Mercedes-Benz dealership performs a diagnosis and confirms that your vehicle has the issue, the repair will be covered under this extended warranty and performed at no cost to you. • This extended warranty does not apply to any other components or conditions beyond the ones mentioned above, and standard warranty terms apply, including the exclusions with respect to extra expenses, as identified in the Service and Warranty Information booklet.

Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5. Cameras 6. Other Park Topics. Cause Various root causes Remedy See attached diagnostic guide.

Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment. Information: Please refer to this document in the warranty claim and, after completing diagnosis, select the damage code corresponding to the component part that caused the problem. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10-P-067691. Information: In this case, do not use a damage code for the speakers in the warranty claim!