Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2007 Mercedes-Benz GL450 owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2007 Mercedes-Benz GL450. The contact stated that the SRS warning light was illuminated. Additionally, the contact stated that while the dealer was servicing the air suspension strut failures, the dealer informed the contact that the vehicle had sustained severe water damage. The dealer informed the contact that the water had leaked from the sunroof through the headliner and onto the floor. The dealer informed the contact the water leak had caused mold on the headliner, and mold and corrosion on the floor, where the battery and electrical wires were located. The dealer informed the contact that the water entry had caused electrical failures, causing the driver's side and passenger's side third-row windows and the horn to become inoperable. The vehicle was not repaired. The contact related the failure to an unknown recall. …
While driving to work this morning, I turned on the drivers side seat warmer. Less than three minutes later, I noticed a strong odor followed by a considerable amount of smoke and heat coming from the side of the seat nearest the door. I felt what I thought was something poking me in the left rear pocket of my pants, and burned the back of my knuckle checking for the source of the heat. I immediately shut off the heater and pulled off at the first safe location. I exited the vehicle (a pall of smoke followed me) and knocked the smoking embers out of the vehicle (a hole larger than a quarter is burned in the seat). I also noticed a hole was burned through my pants. Apparently, I came very close to significant personal injury, not to mention the fact of possible loss of control of the vehicle. We called the dealer and they scheduled the car for next Monday. …
Tl-contact owns a 2007 Mercedes gl 450. Contact looked online for recall for vehicle.mileage on vehicle is 99,801. Contact was going 66mph at time when drivers seat caught fireand contact was driving on highway. Mercedes heated seats recall for seat overheating and hole burning in drivers side seat. 0 recalls associated with this VIN
Heating element in drivers side defective. The car seat caught on fire. Mercedes refuses to fix under warranty. Will only cover 25% of a 1400$ repair. This does not include the damage done to the seat.
Driving in new jersey on route 80 west for 1-2 miles there was a strong odor of burnt wires that smell so bad and have noticed that the smoke was coming from underneath the passenger seat. It went on for few minutes where the wires actually caught on fire and melted together. Stopped the car, shot the engine off, with windows open and tried to pull the wires apart to prevent further damage.... But could not separate the wires from each other. Called the mb dealer near our location and brought the car in after the mbusa suggested towing it in and later we were told that the vehicle was safe to drive to the dealer. The local mb dealer manager I talked to was very helpful and understandable and he tries to support me the best way he could where he agreed to look at the car at reduced rate to help out to try to figure out the issue. The car is at the mb dealer now. …
I was driving my family to an afternoon lunch on the 5th of December, 2014, the day was chilly and it was a good time to have the heated seats on... After about 10 minutes of driving I noticed a burning smell and thought it was something in the area (it was actually my seat lighting me on fire), needless to say the smell continued to get worse and I knew something was wrong. I looked for a safe area to pull over and identify the source of the smell, before I was able to get off the road my side started smoking and lit on fire. I frantically pulled off the road and jumped out. I then proceeded to rip of my jacket and put out the smoldering section of it. …
When starting the vehicle, the horn intermittently goes off and will not stop. Must turn off the car to get the horn to stop sounding. Then, must turn on the car and turn off the car a few times to make it stop until it all starts happening, randomly, again. Took the vehicle to the Mercedes dealership where car was purchase and has been routinely serviced and they said the problem was a faulty steering wheel switch. The only way to fix the issue is to replace the entire steering wheel itself. The cost for an identical factory wood steering wheel (which is what the car was purchased new with) is $3,000; if we opted for a leather wrapped steering wheel instead the cost would be $1500. The other workaround is to pull the fuse and not have a horn at all. This is a safety issue and should not cost this much to have a steering wheel switch replaced! …
I was driving in my son [redacted] to his school in wayne new jersey with my gl 450 seats warmer turned on in both the drivers and passenger seats. I started smelling smoke & thought it was from outside. I opened my window, and smoke started swirling inside my car and started getting thicker within minutes. I try to search for the source of the strange smell - but no obvious clue observed. When I reached my destination I noticed that the seat has burned a hole in my suit jacket back left side. The hole in the car is on the left side of the drivers seat. I have not contacted Mercedes Benz service and would like to know what I should do if possible. I would appreciate directing me to the appropriate line to fix my seat and electrical system of my Jeep and get compensated for my suit damage asap.
Tl* the contact owns a 2007 Mercedes-Benz GL450. While driving various speeds, the ABS indicator illuminated and remained lit. In addition, the ESP and check engine indicators also illuminated. The vehicle was taken to an independent mechanic who diagnosed that all the wheels needed to be replaced and referred the contact to the dealer .the contact called Mercedes-Benz of south orlando at [phone] (located at 4301 millenia blvd, orlando, fl 32839) and was informed that the parts were on backorder. The manufacturer was not made aware of the failure. The vehicle was not repaired. The failure mileage was approximately 190,000.
I was in my 2007 Mercedes GL450 and had driven approx. 2 miles with my front driver's seat heater on. I started to notice a strange smell and suddenly the cabin was starting to fill up with smoke. I immediately stopped the vehicle and discovered the left side of the back of my front drivers seat was on fire. Snow was on the ground so I scooped up snow to pack in the fire/hot spot which had burned a large hole through the vinyl and inside padding material. I later noticed that my jacket had burn marks and a hole in the exact location of the point of the fire.
Electrical complaints in other GL450 years
Frequently asked questions
How common are electrical problems on the 2007 Mercedes-Benz GL450?
NHTSA has 27 complaints about the electrical system of the 2007 Mercedes-Benz GL450, 23% of the model year's 115 complaints. The component named most often is horn (2 mentions).
Is there a recall for 2007 Mercedes-Benz GL450 electrical problems?
No. NHTSA lists no electrical system recall for the 2007 Mercedes-Benz GL450, though it has 2 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2007 Mercedes-Benz GL450 electrical problems start?
Half of the complaints with a recorded mileage happened before about 107,000 miles, and 5% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 11 fires and 3 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.