72 of the
603 complaints filed about the Mercedes Benz ML350
are about the electrical system —
12% of everything owners reported.
The worst model year for it is 2014.
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
NHTSA complaint #11741266 — an unverified report by a vehicle owner.
In mid-trip as we were going down the highway went to change lanes and the turn signals were no longer functioning. No errors, no alerts, no warnings they just stopped working. After pulling over and turning off the vehicle and turning back on they work for a time then stop working again. After researching with other owners of these and similar model Mercedes Benz vehicles this is a prevalent and highly dangerous safety issue that many many others have experienced.
NHTSA complaint #11711956 — an unverified report by a vehicle owner.
Good morning ! I am an owner of a 2013 ML 350 . I live in San Diego ,CA ,92103 . I was driving my car on [XXX] and it was raining a lot . After around 30 miles I got to my destination parking area and my car died 20 feet away from the parking zone .I tried to reignite it but it wouldn’t start . I checked it with a OBD2 scanner and it was indicating a code U0109 - Lost communication with fuel pump control module . After looking into solutions and reasons for the issue online I came across a post regarding an existing recall with NHTSA with ID 22v955 regarding water intrusion in the spare wheel well portion of the trunk( The Wheel well is not water proofed and doesn’t have a drain port for water to escape ) . I proceeded with inspecting the area and of course it was full of water . The fuel pump control module is located in that area and it was damaged which shorted it and cause the malfunction of the vechile and the error code U0109 stated above . Tried calling Mercedes Benz but they confirmed about that specific recall but said my VIN is not part of it and I should file a claim or complain with you . I will attach proof and pictures of the water and the damaged component. My car now need to be towed and fixed on my expense because of Mercedes Benz negligence… Hopefully you can add my car to this recall and when this happens I would get some kind of reimbursement… Thank you for your time and understanding. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11699776 — an unverified report by a vehicle owner.
Vehicle: 2014 Mercedes-Benz ML350 VIN: [XXX] I have experienced repeated failures of the Blind Spot Assist / driver-assist system since purchasing this vehicle. When I first purchased the ML350 in Texas, the vehicle already showed warning messages (“Blind Spot Assist Inoperative / Pre-Safe Function Limited”). The dealer attempted repairs before delivery, but the defect persisted. After moving to New York, the problem continued. On June 26, 2023, I took the vehicle to The Automaster Mercedes-Benz in Shelburne, VT. Their diagnosis confirmed water intrusion into the blind spot radar sensors, consistent with Mercedes-Benz TSB LI54.71-P-056477. Both left and right sensors and wiring require replacement. This is a safety defect because Blind Spot Assist and Pre-Safe features are disabled without warning, increasing risk of collision when changing lanes. Many other owners have reported the same issue, and Mercedes has issued a TSB acknowledging the defect, but no recall has been provided. I request that NHTSA investigate this recurring safety problem and require Mercedes-Benz to provide coverage or a recall for affected vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11688328 — an unverified report by a vehicle owner.
I purchased a used Mercedes-Benz from Freehold Mitsubishi in early 2024. Within hours, serious safety issues appeared, including a check engine light, cylinder misfire, EVAP leak, traction control failure, and blind spot assist malfunction. The vehicle’s ECM and wiring harness were later found damaged due to oil leaks and electrical shorts. Despite multiple repair attempts, the vehicle was returned in worse condition and remains unsafe to drive. I am reporting these issues due to their potential risk to vehicle safety.
NHTSA complaint #11670372 — an unverified report by a vehicle owner.
I purchased my car used at the Mercedes dealership in Tyler Texas June 2023. I took all my savings and paid cash and was told that the car was impeccable shape and there were no current issues and all the service records were up to date. November 2023 is when everything started happening and my engine light came on. It was revealed to me by a service tech that I was sold the vehicle with an existing major oil leak /seals broke. Etc. SEE Attached invoices. I have endured driving down the road and my car just giving out and losing power steering. The car has been sputtering and there have been misfires, fauled fuel injectors, coils, s and spark plugs, oil leaks, fuel pump leaking gasoline in the engine and smoke coming from the hood. I thought my car was going to start on fire it smelled like a hot electrical wires and gasoline. My nerves are frayed from this car because of how many times it has broke down. I have missed work because of the car, I'm behind on my home bills, I missed my airline flight to see my sick father, I have had to pay for rental cars, all due to this vehicle. I am very concerned for my safety in this vehicle and I would like the vehicle fixed at the expense of Mercedes or my money back. Thank you, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11657305 — an unverified report by a vehicle owner.
I believe the electrical system may be defective as ever since I have had it the light bulbs frequently have to be changed. We own three vehicles in my households (the other 2 are non-Mercedes) and none of my other vehicles do this. The latest issue with the electrical system is that the rear tail lamp and power lift gate. I was told there was water that was getting in from somewhere but mechanic could not find where. I need a new SAM module and that is why my power lift gate motor does not work. As I did some research online, the same exact problem was recalled on a the same model but the 2009 model and I have the 2011 model. I believe my car should be part of the same recall which I believe is Mercedes recall number 2009030003. That appears to be a faulty seal around the rear tail lamp assembly. I believe this is a manufacturer's defect that should be covered and would likely explain why I have had to change out light bulbs so many times over the years.
NHTSA complaint #11647608 — an unverified report by a vehicle owner.
My name is [XXX] My vehicle cut off on me 3 times twice while stationary and once at an intersection. Found oil in engine control module due to failed cam position sensors. Oil has traveled through the engine harness to ECM causing oil to get into module and cause it to shut down but it did start back up. This is very dangerous and could cause serious injury to someone. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11637887 — an unverified report by a vehicle owner.
Turn signals will not operate, dealership quoted me $1400 3 years ago, had the work performed and now the issue is happening again and I am being quoted the same amount of money. This is a safety concern if I cannot signal to others where I am turning!!!!! This could cause an accident!!!!! This is highly unsafe!!! What if my kids were in the car?! Talking to customers in waiting lounge at dealership other people have had same issue!! The one time they stopped working I had a person hit me going 30 mph, could have been much much worse.
NHTSA complaint #11603923 — an unverified report by a vehicle owner.
Started to have an issue with the blind spot assist showing inoperable. Shortly after depending on the outside temperature the AC would start shutting off and on. The days the temperature was above 95 degrees the AC would suddenly stop working. Took the vehicle to the dealer for AC service. Dealer reports the engine "back" wiring harness had been rubbing, exposing and chaffing the harness wires, and for safety concerns a complete harness replacement is necessary. When asked how was this possible since the harness clearance is a manufacture design. Was told it happens on these vehicles and currently there is no recall.
NHTSA complaint #11603207 — an unverified report by a vehicle owner.
ML350 engine stalled while driving on an expressway and would not turn back on. ML350 needed to be towed where it was determined that water accumulated in the spare tire wheel well, leading to the fuel pump short circuiting. This is directly related to NHTSA campaign 22V955000. That recall repair was completed prior to this incident. Per the technician, the recall repair installed a water drain plug to prevent the water accumulation. This repair effectively failed - the drain plugs malfunctioned and were not allowing water to drain. MBUSA deny’s responsibility for the failing drain plug - stating that the trunk weatherstripping is the root cause, not the failing drain plug. This is an unacceptable response and worth of the recall being expanded. The fuel pump control unit can still short out if MBUSA’s poor excuse of a recall fix fails as it did with mine.
NHTSA complaint #11598349 — an unverified report by a vehicle owner.
Vehicle will not crank/start intermittently key turns in the ignition but nothing happens. Front door on the right and left will not operate and have to push down locks in order for vehicle to lock and prevent vehicle/ property theft.
NHTSA complaint #11582839 — an unverified report by a vehicle owner.
Turn signals stop working after driving a mile or so. If possible, I turn the car off and on. Turn signals work but fail again within a few miles. Hazard light work even when the turn signals fail. I’ve read this is a common issue searching the internet. Definitely a safety concern
NHTSA complaint #11541795 — an unverified report by a vehicle owner.
Blind spot assists and turn signals go out without warning. This model should have been included in the previous recall for timing. Having the same issues as other recalled cars.
NHTSA complaint #11540845 — an unverified report by a vehicle owner.
I am writing in regards to my 2014 ML 350 Suv. The check engine light came on and upon taking it to the mercedes dealership, I was told the issue is that the camshaft adjusters have failed and need to be replaced. The cost quoted is over $11,000 to repair. Upon further investigation I found reports on multiple lawsuits for the Mercedes C series for the same year (2012-2014) that resulted also in a recall whereby customers were given a recall to replace at no charge the camshaft adjusters up to 120k miles. My car only has 83k and I am told by two independent mechanics that the camshaft adjuster should not be failing like this and that this has been an ongoing issue with Mercedes. The safety issue is that I am told by independent mechanics that what could happen over time is that I could be driving and the entire engine/power just shuts off. This could even happen at high speeds on the highway. The mercedes dealer tells me there is no safety issues that could result from camshaft adjuster problems which doesn't appear to be true as per the other independent mechanics. I request further investigation into this issue because as per the independent mechanics its the "same engine" as the 2012-2014 that are under the recall . I'm requesting a recall on this for my car that Mercedes pays for. This should not be failing especially in a car with only 83k on it . If the C series 2012-2014 received recall on this part then I also think my ML 350 should be covered. Mercedes customer service tells me they cannot pay for the repair, they said I could file complaint for recall through NHTSA Thank you .
NHTSA complaint #11511621 — an unverified report by a vehicle owner.
The steering column does not operate properly. The column no longer adjusts positions and more importantly, the turn signals work ad-hoc. When you start the vehicle, the turn signals tend to operate properly; however, after driving for approximately 15 minutes, the turn signals operate sporadically. THIS IS A SAFETY CONCERN as it's impossible to know when the turn signal will operate correctly or not, thus creating a hazard to me and others on the road. It is my understanding from investigating this online that this is a systemic issue with this model and not unique to my vehicle (just google "2012 Mercedes ml350 turn signal problems"). I discussed this with Mercedes Benz USA and they told me that the only way to resolve this issue is to replace the steering column (part #: 166-460-62-00) at the cost of $3,373.81. I hope that the NHTSA investigates this further as Mercedes-Benz has decided to ignore this safety issue that may cause harm or death. Sincerely, [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
NHTSA complaint #11511019 — an unverified report by a vehicle owner.
Known defect with timing issues that give code P0016. All cars should be part of this recall regardless of mileage on a known defect. This repair is extremely expensive and wouldn’t be needed if built correctly.
NHTSA complaint #11510655 — an unverified report by a vehicle owner.
The contact owns a 2014 Mercedes-Benz ML350. The contact stated that while at a stop light, the vehicle lost motive and electric power and stalled without warning. The contact restarted the vehicle, but the vehicle failed to remain running. The vehicle was towed to an independent mechanic and the contact was informed that water had intruded into the rear of the vehicle causing electrical failures. The vehicle was not repaired because the Insurance Company deemed the vehicle a total loss. The manufacturer was contacted but offered no assistance. The failure mileage was 60,000. The contact stated that the interior of the vehicle has to be dried out first in order to assess the damage to the electrical system. The contact noted the failure mileage was 60379.
NHTSA complaint #11504527 — an unverified report by a vehicle owner.