Mercedes-Benz ML-Class Complaints

497 consumer complaints on file.

#11773888October 27, 2026
FUEL/PROPULSION SYSTEM
*2012 ML550 benz fuel pump control module Re: Formal Demand for Repair – Fuel Pump Control Unit Replacement Vehicle: Mercedes‑Benz ML550 VIN: [XXX] Recall: NHTSA Recall Campaign No. XXX To Mercedes‑Benz USA: I am submitting this formal demand for repair of the cost to replace the fuel pump control unit in my Mercedes‑Benz ML550. The vehicle stalled without warning while in operation, creating an immediate safety hazard. A certified mechanic diagnosed the issue and confirmed that the fuel pump control unit was reporting a fault through the onboard diagnostics system, accompanied by an illuminated check engine light. Due to the intermittent nature of the defect and the risk of sudden failure, replacement of the fuel pump control unit was the only available remedy. During my extensive research, I become aware of NHTSA Recall Campaign No. XXX, which identifies defective fuel pump control units in this vehicle model. The failure I experienced, the diagnostic findings, and the circumstances of the stall are consistent with the defect described in the recall. I purchased this vehicle from an authorized Mercedes‑Benz USA dealer, and my personal contact information was collected at the time of sale. I did not receive any recall notification from Mercedes‑Benz USA. As a result of this failure to notify, I strongly recommend repair expenses should be covered under the recall campaign. The defective fuel pump control unit was identified by the mechanic after the symptoms and diagnostic information acquired. Thanks you INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11773203October 23, 2026
FUEL/PROPULSION SYSTEM, ENGINE
Vehicle: 2013 Mercedes-Benz ML350 BlueTEC (OM642 3.0L V6 Turbo Diesel) Current Mileage: Approx. 117,925 miles Dealer / Location: Mercedes-Benz of North Scottsdale (RO #260467) Summary of Safety Issue & Defect: The vehicle is experiencing an active liquid diesel fuel leak from a replacement fuel pump assembly that was previously installed by an authorized Mercedes-Benz dealership four years ago. Active diesel leaks directly over/near hot engine and exhaust components pose an acute, severe vehicle fire hazard and expose cabin occupants to toxic diesel fumes. Additionally, the vehicle exhibits a severe oil leak in the engine inner-V caused by prematurely degraded factory oil cooler seals (addressed in Mercedes TSB LI18.30-P-055434), along with an active DEF reductant heater circuit fault (DTC P20BD). The dealership confirmed the fuel leak but refused to rectify or honor Goodwill coverage for the prematurely failing fuel pump, presenting a repair quote exceeding $14,000. Active fuel component leaks present an unreasonable safety risk to vehicle occupants and surrounding traffic.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11769741October 7, 2026
ELECTRICAL SYSTEM, FUEL/PROPULSION SYSTEM, ENGINE
MBUSA CLAIM #24526507 - 2013 MB AMG ML63 Engine Signed - my vehicle is not drivable due to random sudden engine stalling at highway speeds, electronic failures, gear-shifting lockouts, hazard alert/radar failures, and distronic system crashes. i have spent over $37,000 out-of-pocket at authorized manufacturer service centers, and recurring check engine lights have required multiple flat-bed tows. yet to date, zero safety recalls have been accurately addressed and fixed by the franchise service centers. instead, i have been charged for unnecessary repairs, marked-up parts, and inflated labor rates. subsequent to purchasing, i have driven less than 29,000 miles, yet have been repeatedly pressured by management to trade in the vehicle at a low-ball price, $12,000. upon reviewing a restored franchise multi-point inspection video, original service invoices, vehicle history report, and five safety recalls issued for this vehicle class, i have cause to allege required recall work was systematically not performed. It continues to stall on highway for 3 years and the inspection video explicitly captures active trouble codes fscu07 and p1ccf displayed on shop terminal screen. an independent service center reported active codes b210d00, p008700, p008a00, confirming failures in the fuel pump and injector system, oil-soaked engine wiring harness, failed camshaft sensors and solenoids, and active water pooling and rust in the wheel well; meaning the vehicle presents an immediate physical crash hazard to myself and all surrounding highway traffic.furthermore, the manufacturer has failed to deploy an independent safety investigator under open mbusa claim 24526507, on 9.25.2026. instead, an escalation manager called that night and said, due to age of the vehicle and its out-of-warranty status, neither MBUSA nor NHTSA would be interested or inclined to follow up on these safety complaints, telling me that these severe recall non-compliance issues are strictly dealership matters.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11767350September 28, 2026
SERVICE BRAKES, HYDRAULIC
The contact owns a 2011 Mercedes-Benz ML350. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed and went to the floorboard. The vehicle failed to stop at the stop sign. The contact swerved to the right and struck the curb. The vehicle was then driven to the residence. The manufacturer was made aware of the failure and informed the contact that the vehicle was previously repaired under NHTSA Campaign Number: 22V315000 (Service Brakes, Hydraulic). The failure mileage was approximately 129,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11761320September 1, 2026
EXTERIOR LIGHTING
Turn signals stop functioning during drive cycles. This functionality is lost for the remainder of the current drive cycle and can be restored with a key cycle. It does not occur every drive cycles and is unpredictable.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11751996July 22, 2026
ENGINE, SERVICE BRAKES, HYDRAULIC
The contact owns a 2011 Mercedes-Benz ML350. The contact stated that while driving approximately 60–65 MPH, the brake pedal was depressed and the vehicle started sliding. The contact stated that the vehicle stalled. The brake warning light was illuminated. The vehicle was towed to a tow lot. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 88,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11749928July 13, 2026
STEERING, POWER TRAIN, SERVICE BRAKES, HYDRAULIC
The contact owns a 2012 Mercedes-Benz ML350. While the contact’s wife was driving approximately 30 - 35 MPH, the message "Do Not Drive Vehicle" was suddenly displayed. The vehicle was taken to a mechanic, and the brake fluid reservoir was topped off. The mechanic was unable to find any leaks. The vehicle was not diagnosed or repaired. The message turned off and was displayed again 4 hours later. The contact was called by his wife, and the vehicle was driven to the residence after the brake fluid reservoir was refilled. The contact stated that a half mile later, the message was displayed again. The vehicle was driven to the residence and parked. The dealer was contacted and confirmed that there was no recall associated with the VIN related to the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 122,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11746608June 26, 2026
STEERING
Steering became increasingly sluggish and difficult to navigate; i took the vehicle into the shop and they said there is metal shards or shavings being worn into the power steering fluid and destroying the pump, clogging up the filter and the rack and pinion steering system is also being compromised making the vehicle unsafe to operate.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11741266June 1, 2026
ENGINE, ELECTRICAL SYSTEM, FUEL/PROPULSION SYSTEM
NHTSA VEHICLE SAFETY COMPLAINT SUPPORTING STATEMENT Vehicle: 2013 Mercedes-Benz ML350 I am submitting this complaint regarding a continuing safety concern involving water intrusion and electronic system damage in my 2013 Mercedes-Benz ML350. My vehicle was subject to a Mercedes-Benz recall involving water intrusion and related components. Despite recall-related repairs being performed, moisture and water intrusion concerns remain unresolved. During the diagnostic process, Mercedes-Benz personnel identified evidence of water and humidity in areas associated with vehicle electronics and control modules. The vehicle has experienced repeated mechanical and electronic issues following discovery of the water intrusion condition. Multiple repair facilities have been involved, and I have incurred significant diagnostic and repair expenses while attempting to determine the full extent of the damage. The primary concern is not ordinary wear and tear. The concern is that water intrusion has affected vehicle systems and that the recall remedy has not resulted in a complete resolution of the condition. I am concerned that moisture exposure may continue to impact vehicle electronics, control modules, sensors, and other safety-related systems. Mercedes-Benz USA has been notified and a case has been opened. The dealership has also been involved. However, despite escalation requests and requests for management review, I have not received a meaningful resolution. The dealership continues directing me back to Mercedes-Benz USA while Mercedes-Benz USA has not provided a final management response. I respectfully request that NHTSA review whether the recall remedy adequately addressed the water intrusion condition and whether additional investigation is warranted regarding continuing moisture intrusion, electronic system exposure, and potential safety risks associated with this condition. I am prepared to provide repair orders, recall documentation, photographs, diagnostic findin
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11739473May 22, 2026
FUEL/PROPULSION SYSTEM
The failed/malfunctioning component appears to be the fuel pump controller / fuel pump control unit, and possibly the fuel pump system. The Mercedes-Benz dealer identified water/moisture-related damage and corrosion at the fuel pump controller area. The failed component should be available for inspection if the dealer preserves the part during repair. I have requested that the dealer not discard the damaged component. My safety and the safety of others were put at risk because the fuel pump controller is related to fuel delivery. If it fails, the vehicle may not start, may lose fuel supply, or may stall while driving. This creates a safety risk, especially if the vehicle stalls in traffic, at an intersection, on a highway, or during normal driving. The problem has been confirmed by a Mercedes-Benz dealership. The dealership diagnosed water/moisture damage to the fuel pump controller area and provided an estimate of $768.22 for fuel pump controller replacement, plus $244.88 for the inspection fee. The dealer also indicated that this was the first inspection and that the fuel pump itself may also need further inspection or may have related damage. The vehicle/component has been inspected by a Mercedes-Benz dealership. Mercedes-Benz USA / the manufacturer’s representative has also reviewed the case through its goodwill process, but they refused to treat it as recall-related coverage. To my knowledge, the vehicle has not been inspected by police or insurance representatives. Prior to the current failure, the vehicle had starting/no-start related symptoms beginning around the middle of 2023. The engine could not start successfully at times. I do not recall receiving a clear warning lamp or message specifically identifying the fuel pump controller before the failure. However, the symptoms were consistent with a fuel delivery problem, and the dealer later confirmed water/moisture corrosion damage in the fuel pump controller area.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11738634May 18, 2026
VISIBILITY:SUN/MOON ROOF ASSEMBLY
The contact owns a 2014 MERCEDES-BENZ E350. The contact stated while driving 60 MPH on the freeway, there was a popping noise coming from the sunroof and discovered it was shattered. The vehicle was not taken to the dealer or an independent mechanic for diganoses .The vehicle was not repaired The manufacturer was not notified of the failure. The approximate failure mileage was 108,000 .
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11734678April 29, 2026
FUEL/PROPULSION SYSTEM
Re: My 2013 ML350- Intermittent Start/ Vehicle cutting off while in heavy traffic. Fuel Pump and Fuel modulator failed due to water collecting in the spare tire wheel-weld causing water intrusion into the fuel system. I paid out of pocket for this service twice, AND then found out from MB Tacoma there was a RECALL with the exact same issue. I took the vehicle in to the closest dealer- Seattle Mercedes to handle the outstanding recall issues. I was advised to contact MERCEDES BENZ USA GOODWILL DEPARTMENT. My initial claim was approved, as I submitted ALL DOCUMENTATION of the repairs related to this issue. NOW, after 5 months of my RECALL REIMBURSEMENT CLAIM BEING BOUNCED AROUND by customer service agents that were not trained to handle recall issues- my dealership needed approval to process it. I even provided MB-USA w/a Bulletin # (FROM MB-USA) that clearly states to claim reimbursement IF THESE PARTS FAILED AND THE CUSTOMER PAID OUT OF POCKET.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11732942April 22, 2026
SERVICE BRAKES, HYDRAULIC
The contact owns a 2011 Mercedes-Benz ML350. The contact stated that while the vehicle was parked and turned off, there was brake fluid leaking from the vehicle with the BRAKE warning light illuminated. The dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was not available.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11731177April 14, 2026
FUEL/PROPULSION SYSTEM
ENGINE STALLED DRIVING ON INTERSTATE HIGHWAY AT 70mph. MECHANIC DIAGNOSTIC INDICATED TO BE FAULTY FUEL PUMP and/or FUEL PUMP CONTROL UNIT. THIS ISSUE HAS BEEN RECOGNIZED BY MERCEDES BENZ AS A FAULTY ISSUE AND SUBJECT TO RECALL. UPON CALLING MERCEDES BENZ DEALER WAS TOLD THERE WAS NO RECALL ON THIS MATTER FOR MY VEHICLE CONTRADICTING THIS ISSUE PREVIOUSLY RECOGNIZED BY MERCEDES BENZ.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11729477April 6, 2026
FUEL SYSTEM, DIESEL, FUEL SYSTEM, GASOLINE
The contact owns a 2014 Mercedes-Benz ML350. The contact stated that while driving at 35 MPH and accelerating above 40 MPH, the vehicle failed to accelerate above 40 MPH before it lost automotive power. The vehicle was driven back to the residence. The vehicle was diagnosed by the dealer, and the failure was associated with NHTSA Campaign Number: 22V955000 (FUEL SYSTEM, DIESEL, FUEL SYSTEM, GASOLINE); however, the VIN was not associated with the recall repair. The vehicle was repaired out of pocket. The manufacturer was notified of the failure. The failure mileage was 115,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11724121March 13, 2026
FUEL SYSTEM, GASOLINE, ENGINE AND ENGINE COOLING, SUSPENSION
The contact owns a 2014 Mercedes-Benz ML63 AMG. The contact stated that the vehicle was experiencing front suspension, coolant, and oil leak failures. The contact stated that the front suspension unexpectedly lowered while the vehicle was parked or while driving. The message "Active Curve System Malfunction" was displayed. The vehicle was towed to the dealer, where unknown repairs were performed. Additionally, the contact noticed a coolant leak in the garage, where the vehicle was parked. The vehicle was taken to two certified independent mechanics, where unknown repairs were performed; however, the failure recurred. The vehicle was taken to the dealer, where the seals were inspected and corrected, and it was diagnosed that the front left cylinder and the lower and upper radiator hoses were leaking. Additionally, a leak was found at the firewall connection. The vehicle was repaired; however, the failure recurred. The vehicle was taken back to the dealer, where the same assessment was made, and the vehicle was repaired; however, the failure persisted. The contact stated while at a complete stop at the red traffic light, the vehicle stalled and failed to restart. The vehicle was pushed into a parking lot with assistance. A warning light for key fob battery drainage was illuminated. The vehicle was towed to an independent mechanic, where the failure was related to an unknown recall, and the contact was referred to the dealer. The contact stated that the dealer had previously completed the repair of NHTSA Campaign Number: 22V955000 (Fuel System, Diesel, Fuel System, Gasoline); however, the recall repair had failed to fix the vehicle. The vehicle recently stalled and was towed to the dealer, where it remained. The vehicle was not repaired. The manufacturer was notified of the failure, and the case was escalated to an Executive. The failure mileage was approximately 100,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11723746March 12, 2026
SUSPENSION, ENGINE, POWER TRAIN
On December 6, 2025 I purchased a used 2013 Mercedes-Benz ML63 AMG from Jaguar Land Rover Willow Grove (Piazza Auto Group) in Pennsylvania. The delivery documentation for the vehicle included a written service commitment stating: “Replace air compressor for suspension system.” On January 23, 2026 at approximately 6:30 PM, while operating the vehicle at highway speed on the [XXX] in [XXX] , the vehicle experienced a sudden cooling system malfunction. An “Engine Overheat – Shut Off Engine” warning appeared on the instrument cluster and steam began emitting from the engine compartment. Because the failure occurred while traveling at highway speed, the driver was forced to execute an emergency maneuver across traffic lanes in order to reach the shoulder safely. The vehicle became disabled and required towing. The vehicle was transported to a Mercedes-Benz dealership for inspection. Initial repairs involved replacement of the coolant reservoir and hose assembly. Within several days the vehicle again displayed a low coolant warning and was returned for further inspection. At that time the radiator was found to contain a prior non-OEM epoxy repair and the radiator required replacement due to leakage. During a separate independent inspection, the air suspension compressor was observed to be mounted using plastic zip-tie fasteners rather than mechanical mounting hardware. The compressor is part of the vehicle’s AIRMATIC suspension system and is subject to vibration, pressure cycling, and heat during normal operation. Improper mounting of this component could allow the compressor assembly to move or detach during operation and may damage associated air lines or electrical connections. Because the air suspension system affects ride height and vehicle stability, this condition may present a safety risk during vehicle operation. Photographs and video documentation of the compressor mounting condition are available for inspection upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11722017March 4, 2026
SERVICE BRAKES, HYDRAULIC
The contact owns a 2011 Mercedes-Benz ML350. While the daughter was driving at an unknown speed, several unknown warning lights illuminated on the instrument cluster. The driver heard an abnormal hissing or squeaking sound while depressing the brake pedal. The vehicle was driven back to the residence. The contact’s son then drove the vehicle to a shopping center, and when the brake pedal was depressed, the brake warning light illuminated, and the vehicle unexpectedly entered SAFE Mode. The contact was unable to shift to drive(D). The brake pedal was depressed and went to the floorboard. The vehicle was towed to a dealer. The vehicle was not yet diagnosed or repaired. The contact stated that the vehicle was repaired under NHTSA Campaign Number: 22V315000 (Service Brakes, Hydraulic). The contact stated that the dealer had inspected the brake booster, but no parts were replaced. The contact related the brake failure to the recall. The manufacturer was informed of the failure. The failure mileage was approximately 111,000.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11719355February 20, 2026
UNKNOWN OR OTHER
In July 2025, the sunroof panel had lifes and was flapping at highway speeds. I immediately contacted a Mercedes-Benz dealer to report the hazard. I was told they were unaware of such an issue and that I would have to pay for the repair out-of-pocket. Due to financial hardship, I could not afford the repair at that time. in. In early February, while driving on the highway, the entire sunroof panel catastrophically detached and flew off the vehicle. This created an immediate and severe road hazard for other drivers. This incident matches the 'adhesive bonding failure' described in other Mercedes-Benz sunroof recalls (e.g., Recall 21V-197), but my specific VIN was not included in that list.
Crash:
No
Fire:
No
Injuries:
0
Deaths:
0
#11713814January 28, 2026
UNKNOWN OR OTHER
Today at 1/27/25 630 pm my vehicle caught fire.i was told that the vehicle was subject to the Active Curve System (Recall 18V272) and Fuel Pump (Recall 23V010).
Crash:
No
Fire:
Yes
Injuries:
0
Deaths:
0

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