2007 Mercedes-Benz ML350 Problems

What owners report

Owners of the 2007 ML350 most often complain about heated front seats that overheat and burn through the upholstery, sometimes scorching clothing. Electrical problems and transmission misbehavior (harsh or unexpected shifting, going into neutral or limp mode) also come up repeatedly in the sampled complaints.

1. 1
   Seats

   Heated seat overheating and burning through upholstery

   • 30 complaints (36%)
   • median 69,000 mi at 6.1 yrs old (28 state mileage)
   • 23 mention a crash, fire or injury
   • filed 2008–2022

   Owners describe the driver's side seat heater getting extremely hot within a few minutes of being switched on, followed by a burning smell and smoke. Several report a hole burned through the leather and, in some cases, through the clothing they were wearing; the problem stopped when the heater was turned off. Complaints say dealers were notified and in some cases identified the seat back heater as faulty, but the seat was often not repaired. Reported across a wide mileage range, from under 2,000 to over 125,000 miles, typically in cool weather when the seat heater is used.

   2 related service bulletins

   What to check: Switch on both front seat heaters and watch for hot spots, a burning smell or discoloration on the cushion and backrest, and ask whether the seat heater elements or wiring were ever replaced.

   2 excerpts from owner complaints in NHTSA records

   “Wife was idling in car with seat heater turned on. Seat heater caught on fire and burned hole the size of a half dollar in the lower area of the seat in the area of my wife's lower back. Smoke came out of the seat and my wife's coat was damaged. Brought into dealership same day and are waiting for their explanation.”

   NHTSA complaint #10654922, filed 2014-11, 44,275 miles

   “Today, and while driving on a freeway, my car and I almost burned when I turned on the driver seat heater. I started feeling an excessive heat on the left back side. I stoped on the right of the freeway to discover that the seat leather was burned with heating wire, with smoke coming out from the seat. My shirt was damaged with the burn. Searching the web, I found many people complaining about the same issue.”

   NHTSA complaint #11281676, filed 2019-11, 5 miles
2. 2
   Transmission and drivetrain

   Transmission harsh shifting, stuck gear or loss of drive

   Mentioned in 10 of 60 sampled complaints

   Complaints describe the transmission not shifting out of first gear, jumping between gears on its own, dropping from drive into neutral, or delaying engagement from a stop. Some owners had to shut the engine off to reset the system, and a few report the vehicle losing power in traffic. Dealers in some cases replaced the transmission or the transmission electrical plate; others told owners the vehicle was out of warranty. Most reports fall between roughly 25,000 and 85,000 miles, often during low-speed or stop-and-go driving.

   3 related service bulletins

   What to check: Test drive from a cold start in traffic and note any delayed or hard 1-2 shifts, and ask for service records showing transmission fluid changes or electrical plate/valve body work.

   2 excerpts from owner complaints in NHTSA records

   “As I was attempting a sharp left turn the car shifted from d to d1. To recover I placed the transmission in n then back to d, while moving. I continue with no further problems. This was not the first time since it has happened 3-5 times since I bought the car in june 2011 with 43,616 miles.”

   NHTSA complaint #10425949, filed 2011-09, 48,880 miles

   “I purchased my 2007 mercedes benz ML350 on 10/11/14 on 10/24/14 I began having problems with what seemed to the shifting of gears. When trying to slowly excel from either a complete stop or a slow crawl it seems as though the car would not move, it was having a problem automatically shifting from 1st to 2nd gear, and back down from 3rd to 2nd. This has happened several times and has occurred while in traffic endangering my and my families lives. …”

   NHTSA complaint #10654402, filed 2014-11, 81,586 miles
3. 3
   Electrical system

   Electrical faults, water in rear/hatch area and battery

   • 11 complaints (13%)
   • median 80,052 mi at 9.3 yrs old (10 state mileage)
   • 3 mention a crash, fire or injury
   • filed 2010–2024

   Owners report instrument panel lights failing, door locks cycling on their own, the liftgate opening or becoming inoperable, and warning lights staying lit until the battery drains. Several complaints trace this to water entering the rear cargo area and reaching modules such as the liftgate control unit or the SAM module. Some also describe a burning smell from the rear of the vehicle. Often reported between about 30,000 and 110,000 miles, frequently after rain or washing.

   2 related service bulletins

   What to check: Inspect the spare tire well and rear side panels for moisture or corrosion, check that the liftgate opens and closes smoothly, and ask whether any control modules have been replaced.

   2 excerpts from owner complaints in NHTSA records

   “While driving my turn signals, brake lights, windshield wipers, seat controls, and I'm not sure what else became inoperable. Also the srs warning displayed meaning the airbags were malfunctioning. Seems that the sam module is the culprit but nothing should be able to stop such vital safety issues from happening all at once. I have seen several articles about this happening and a recall is needed in my opinion.”

   NHTSA complaint #11163862, filed 2018-12, 40,000 miles

   “While driving down the highway I smelled what smelled like wires burning then my windshield wipers turned on by itself and wiped at a very fast pace, then the horn started blowing (on its own) very loudly, I pulled over at a tire shop and I noticed smoke coming from the rear passenger door panel. The fire department was called and they disconnected the battery. When I spoke to a mechanic I was told that there was a recall on the wiring harness and that was more than likely the problem.”

   NHTSA complaint #11331697, filed 2020-06, 80,105 miles
4. 4
   Steering

   Power steering binding, noise or fluid leak

   • 7 complaints (8%)
   • median 96,000 mi at 7.0 yrs old (6 state mileage, few)
   • filed 2010–2021

   Owners describe the steering becoming stiff or binding, a low-pitched humming noise, and fluid leaking from the power steering system. In one case the dealer replaced the lower steering column section after diagnosing a binding joint; in others the pump and reservoir were replaced. Some complaints link a locked idler pulley and broken serpentine belt to a loss of power steering assist. Mostly reported from about 65,000 to 110,000 miles.

   1 related service bulletin

   What to check: Check the power steering fluid level and look for leaks or weeping near the pump and rack, and listen for humming while turning the wheel at idle.

   2 excerpts from owner complaints in NHTSA records

   “Power steering began making low pitched humming noise, which LED me to discover a power steering fluid leak. Upon doing research online, and talking to mercedes techs, I've found this to be a very common problem with these vehicles. It can and has LED to power steering / rack failure and is a major safety hazard.”

   NHTSA complaint #10653548, filed 2014-11, 110,000 miles

   “Serpentine belt system. While driving on road at the highway speed, one of the idler pulleys locked up due to the failed bearing, leading to damaging/braking serpentine belt. That LED to loss of steering (loss of power steering) and overheating the engine. Created a very danger situation and left my family stranded many miles away from home. Very costly towing service and repair.”

   NHTSA complaint #10924806, filed 2016-11, 107,000 miles
5. 5
   Brakes

   Brake pedal feels soft or vehicle does not stop

   • 14 complaints (17%)
   • median 78,310 mi at 10.1 yrs old (14 state mileage)
   • 8 mention a crash, fire or injury
   • filed 2007–2023

   A small number of complaints describe the brake pedal going to the floor or the vehicle failing to stop, including low-speed collisions where pumping the pedal did not help. Owners also report ABS and stability warning lights and shuddering while driving. Two recalls in the input concern moisture-related corrosion in the brake booster housing that can reduce brake performance. Reported from very low mileage up to about 110,000 miles.

   Recall 24V298000 · DO NOT DRIVERecall 22V315000 · DO NOT DRIVE

   What to check: Have a shop inspect the brake booster and check whether the open brake booster recalls have been completed for this vehicle by VIN, and note any soft pedal or warning lights during a test drive.

   2 excerpts from owner complaints in NHTSA records

   “Reverse pulling out of driveway at slow speed then stopped. On drive position, vehicle jerked forward when gas pedal was applied. This happened twice at same situation about same time.then at the freeway, in stop and go traffic vehicle brakes failed and hit a big-rig truck. No warning light that came on. I pressed foot pedal hard but vehicle did not stop and continued rolling until it rear ended the truck. Luckily our speed was 0-5 MPH and no injury to my 2 passengers. Chp assisted us. Vehicle was normal when pulled over to the shoulder. …”

   NHTSA complaint #10925447, filed 2016-11, 44,415 miles

   “Driving on 295 on new jersey parkway at 60 MPH with seat heater turned on. Seat heater caught on fire and burned a hole, the size of a half dollar in leather seat on the left side of driver seat. The left side of lower back. Smoke came out of the seat and damaged and burned a hole in the leather seat and burned a hole in my coat. Called the dealership same day said there was no recalls. Also engine lights remain on had it fixed once still remains on and brakes lights also going out.”

   NHTSA complaint #10712834, filed 2015-04, 70,000 miles

Buying note. Have a pre-purchase inspection focus on the seat heaters, transmission behavior, rear cargo-area water intrusion and the brake booster recall status. Service records showing transmission and electrical repairs help show how well the vehicle has been maintained.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.