2014 Mercedes-Benz ML350 electrical problems

Filed Sep 19, 2025 · Driver assistance, Electrical · NY

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 the federal safety agency 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)

Filed Jun 30, 2025 · Driver assistance, Electrical · NJ

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.

Filed Apr 28, 2025 · Electrical, Engine · TX

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)

Filed Jul 2, 2024 · Electrical, Fuel system · IL

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 the federal safety agency 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.

Filed Feb 26, 2024 · Electrical · CA

See attached document for complaint

Filed Aug 25, 2023 · Electrical, Engine · AL

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.

Filed Mar 13, 2023 · Electrical, Engine · CA

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 the federal safety agency Thank you .

Filed Mar 7, 2023 · Electrical, Engine · AL

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.

Filed Jan 30, 2023 · Electrical · 60,000 miles · CA

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.

Filed Dec 20, 2022 · Body, Electrical · CA

After a weekend of incessant rain, while driving a short distance (10 minutes) , this low-mileage, well-maintained 8 year old SUV suddenly stalled, Engine appeared to have powered down and the yellow Engine light came up and pressing gas pedal didn't do anything. I was fortunately able to press the Power button once frantically and re-start it once more and pull over to the side but the car refused to power on thereafter. After investigations by the shops, it appears there was water leaking "through" the body of the vehicle and into the area below the interior of the car, short circuiting Fuel Driver and stalling the car (which they subsequently repaired after draining the water and replacing/re-programming the fuel pump driver) before handing it off for the leak identification work. The car was subsequently taken to a specialist shop to figure out the leak, and they are unable to identify any reasonable source of the water leak and insurance is so far claiming this is "wear and tear". In the course of the testing, the *same* issue happened again and the car stalled while driven by the shop personnel and they could hear the sound of water inside the cabin all the way up to the front. They are unable to identify the source(s) of the leak and at this point, the car has been unusable for over 4 weeks as Insurance continues to push back and the shop can't do the additional work to identify the source in the body without insurance approval. I made attempts to contact the manufacturer but their only available contact is their Customer Support (no email/chat option) who refused to discuss this as it didn't pertain to them directly and re-directed me to talk to my own insurance company. I even reached out via Twitter but got no response. This expensive luxury SUV is not just unreliable at this point but *dangerous* where there are mysterious water leaks under natural conditions like rain leading to car stalling while in motion.