2020 MERCEDES BENZ GLS 450 Electrical System Problems

The vehicle, 2020 Mercedes-Benz GLS450, was being backed out of the garage when an electrical failure occurred causing the vehicle to malfunction. This was a major safety issue that caused the entire vehicle electrical control systems to fail as the vehicle would not turn-off. The vehicle eventually turned-off and was not operational. It was towed to a local dealer where we were they discovered that a heating/cooling system hose caused moisture to enter the cab of the vehicle. The end result was major electrical damage to the vehicle control system of the vehicle. This vehicle is my wife's primary means of travel along with our 4 young children. Had this major malfunction occurred while on a highway going at high speeds a parish the thought of what could have happened to the safety of my wife and children. Per attached dealership bill, the dealership was not able to obtain coverage for this $4,255.15 repair bill. In addition, I did find other Mercedes-Benz GLS450 models who were recalled for this very safety issue where moisture in the cab resulted in major electrical control systems of the vehicle.

I am writing to escalate an unresolved service issue with my 2020 Mercedes Benz GLS 450, VIN [XXX] . During a maintenance service on March 6, my trusted independent services shop for 25 years, Carrera Motors in San Mateo CA, identified that the electrical harness of my GLS 450 was significantly damaged. The plastic casing around the wires had effectively disintegrated, exposing the wires directly to the engine. Carrera Motors indicated that this was a serious issue and does not normally occur with a 5 year old vehicle. They encouraged me to contact Mercedes directly. At the instruction of Carrera Motors, I contacted Mercedes customer care on March 10 and was issued a case number (#[XXX]) for the harness issue. She mentioned that someone would get back to me within 3 business days. Unfortunately, 3 days went by without a response. I called and left 3 messages over the next 2 days. Finally, MBUSA returned my call and instructed me to take the car to an authorized Mercedes dealer. At my own expense, I had the car towed from Carrera Motors to Autobahn Motors in Belmont CA on March 18. Mark Nissen at Autobahn was responsible for the service of my vehicle. He and his services team have verified that the electrical harness was seriously damaged and needs to be replaced at a cost of $5,009.99. Replacement is considered critical, and it’s been identified as a serious safety issue. This issue has not been resolved. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

While driving on the New Jersey Turnpike on November 17, 2023, a burning smell was noticed inside the car. The smell lasted about an hour. No smoke was present and the car continued to operate. While concerned, I assumed it was environmental and outside the car. On November 25, 2023 my car threw a 48V battery warning and forcibly shut off. We were not on a highway at the time and were able to pull over to a gas station. MB roadside was called and towed the car to Euro Motorcars Devon of Devon, PA, the local Mercedes-Benz dealer and where I purchased the car and receive service. Over the course of the next few weeks the service department concluded and ultimately determined that there were burnt out cables which were connected to the 48V battery (this is highlighted in the service receipt attached). This repair was not covered under my warranty and lead to a $5,804.56 repair bill. The car was repaired to my satisfaction and the bill was paid in full on December 14, 2023 determined the matter was complete. On or about May 1, I received a recall notice from MBUSA. The ID is 2024040002 and the NHTSA Recall ID is 24V207. This recall specifically called out the 48V battery connections and potential for misconnections to cause fire. This is the exact issue that is clearly articulated in the service report (attached). After six weeks attempting full reimbursement, MB considered the issue closed and their official position was that I was only entitled to $337.08 for the actual recall of the battery connection check. Of course the connections would now be correct as they fixed them and replaced the cables that caught fire. I am escalating this to your department and seek full reimbursement from Mercedes for this repair performed. This failure occurred prior to the recall notice and is the singular event that the recall is to mitigate that happened.

The dashboard screen stops working randomly. This is not related to extreme outdoor temp conditions. Mercedes dealer could not reproduce the problem and therefore could not offer any solution. Problem has happened 5-6 times over the past 7 months. Please watch video below: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Vehicle would not start. 48v battery light came on. Waited 15 minutes, vehicle started, drove to dealership who did diagnosis. Battery replacement required $1800 + $1200 labor. 2020 vehicle with 61K miles. Bought certified vehicle from MBZ dealership, added a MBZ 3 year or 100K mile extended warranty but this battery is considered a wear and tear item not covered. That would be fine except for the fact that this battery issue is well known to MBZ as it has multiple reported instances of failure on vehicles with 6K to 60K miles.

I have noticed a significant issue with the AC vent system of my Mercedes GLS 450. The vents seem to be distributing mold smell already took my vehicle multiple times to park place Mercedes in Dallas and they performed service but the issue is persistent. I have taken the vehicle to my local Mercedes service center, where they attempted to address the issue. However, despite their efforts, the problem has persisted. This defect is impacting not only the comfort of my driving experience but also the overall value and performance of the vehicle. We had GLE in my family that had the same issue we took it to Park Place and complained about this many times and end up selling the vehicle as they never resolved the issue. Vehicle: 2017 MERCEDES-BENZ GLE350 VIN: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

This incident occurred around 5:50pm on Wednesday, September 21, 2022. I was driving on a merge connector between two freeways in San Francisco at about 60mph, when the vehicle threw a series of error codes and warnings on its displays, culminating with “shut down engine immediately”. The first error was a 48V battery system charging failure, and the second was a warning that coolant was too hot. The instrument panel and steering and brakes did not lose power, but the accelerator no longer worked, and the vehicle slowed down to about 35mph. I had to merge across 4-5 lanes of rush hour traffic at this speed (sketchy) to make it to the side of the freeway, and was able to exit safely and stop in a safe spot. Upon turning off the vehicle for a few minutes and then restarting it, a generic check engine light remained on afterwards. I had the vehicle towed to a Mercedes dealer where the fault(s) are currently being diagnosed. According to the dealer, they are in touch with MBUSA Engineering due to the nature of the fault codes. The vehicle had recently undergone a 50,000 mile routine service without any problems being flagged. The safety implications of this incident are clear: with no ability to match the speed of the flow of traffic, I could have been rear-ended or involved in a collision as I limped across the freeway to safety. I am fortunate that the vehicle had enough residual kinetic energy that I didn’t end up stuck blocking a freeway lane in rush hour traffic. Searching online for similar issues, this appears to be a known manufacturing issue with the mild hybrid inline-6 engine in this model of vehicle. For instance, all of the top Google hits for the term “GLS 48V battery failure” yield relevant and similar reports from other drivers, including summaries from consumer lawyers like this one: https://lemberglaw.com/mercedes-benz-gle-battery-electric-problems/

While driving, vehicle has abruptly stopped/engine turned off causing car to not accelerate and come to a stop. One instance was on a busy freeway, causing our family to pull off the interstate with nearly no curb, risking rear-end collision due to the abrupt stalling of the vehicle. In this instance, the 48 volt battery failure warning, engine overheat warning, engine light warning came on. When MCB dealership evaluated the vehicle, there were no stored associated error codes and MCB service returned the vehicle to me saying that the issue did not occur when they drove it. The same issue occurred again 5 months later, this time in a busy intersection, where the car would not accelerate and I was forced to pull of the road. The check engine light as well as other failure lights came on. THe car was returned to MCB service and again, no error codes were stored and the dealership said they could not find the cause of the problem. This vehicle issue (reported to the NHTSA by several other 2020 GLS owners) is a LIFE-THREATENING DANGEROUS VEHICLE PROBLEM . Both times, the engine abruptly failed and the car would not accelerate in the middle of heavily trafficked roads/freeways, which could easily result in a catastrophic accident. Both times, the vehicle did not store the associated error codes, despite the display illuminating several warning lights, including the check engine light. THe unreliability of this expensive vehicle is particularly concerning to me as it is used to transport young children. Mercedes is taking no accountability for this vehicle failure and claims they have not heard of this issue prior, which is clearly inaccurate given that it has been reported to NHTSA by several other GLS owners. This is an enormous safety liability, not only for the owners of this vehicle, but for innocent bystander drivers who could easily have a rear end collision with the car as it fails to accelerate and the engine abruptly stalls/stops.

MBUX Failure Customer sold MB GLS450 with all season MB Floor matts, Water on shoes drains on floor matts, car is driven and when braking water floods the underneath the front passenger seat and enters the MBUX and shuts down all electronics. This was identified as an issue with Mercedes Benz and they are recommending a part that does not exist for a long term repair. Mercedes not taking responsibility for damage to MBUX. Cost 8350 to repair

The vehicle warnign system displayed "48v Malfunction." Vehicke lost all acceleration in the middle of the highway. The vehicle was just returned3 days ago after undergoing a state inspection at the MB dealership. In looking at the issue on line this appears to be a known problem to Mercedes. They are even facing a class action lawsuit for it in the same model year GLE, which is based on many of the same systems. SOmeone is going to get killed when their vehicle stalls in the middl eof the highway.

Upon starting the car, the screen of the 2020 Mercedes Benz GLS 450 remained blank. This includes the portion of the dashboard that reads speedometer, gas, temperature, RPM. The engine was running and truck could still be driven. The vehicle is available for inspection upon request. This is a major safety issue as the driver does not have visibility to the dashboard with all it's important information. The vehicle is currently at Mercedes Benz dealership undergoing diagnostics. The vehicle is being inspected by Mercedes Benz (manufacturer). See prior comment. There were no warning lamps or messages that appeared prior to the problem. Shortly after driving home (with the blank screen) the car was shut off and restarted and the display came back on but then the check engine light was displayed.

The vehicle issued a “48v battery malfunction” and the car warned me not to drive the vehicle under any circumstance. This was while driving at 55 mph on a country road. The dealer I bought the car from had 3 other cars brought in for the same issue. The dealer my car was towed to said they just had one with the same issue come in. Based on my reading, this is a serious issue and it appears that changing the battery does not correct the issue. I was transporting my entire family at the time. The thought of not being able to break when traveling at high speeds is terrifying. Seems to be a widespread issue on the newer cars. Mine is only a year old.

WE PURCHASED A NEW 2020 MERCEDES BENZ GLS 450 IN OCTOBER 2019 FROM THE OAKLAND DEALERSHIP AND SHIPPED THE CAR TO HAWAII. THE VEHICLE IS NOW 117 MONTHS OLD AND HAS ABOUT 4100 MILES. BECAUSE OUR VEHICLE IS LIGHTLY USED WE ARRANGED FOR MERCEDES BENZ TO SUPPLY AND INSTALLED A 'BATTERY MINDER' TO KEEP THE VEHICLES 48 VOLT SYSTEM CHARGED WHEN WE ARE AWAY FOR AN EXTENDED TIME. HOWEVER WE DID NOT HAVE THE BATTERY MINDER HOOKED UP AT THIS TIME BECAUSE WE ARE USING THE VEHICLE ON A WEEKLY BASIS. ON MARCH 7, 2021 WE EXPERIENCED A "48 VOLT BATTERY MALFUNCTION' WHICH LEFT OUR CAR DISABLED ON THE SIDE OF AN UPHILL MAJOR ROADWAY. THERE WAS NO WARNING JUST A SUDDEN EXTREME LOSS OF POWER, SUPPLEMENTAL SYSTEMS SUCH AS THE AC DEACTIVATED, WARNING LIGHTS FLASHED AND OUR VEHICLE COASTED TO THE SIDE OF THE ROAD. I BELIEVE THE BRAKE SYSTEM WAS ALSO DIMINISHED BY THE LOSS OF ELECTRICAL BOOST. AFTER A WHILE WE WERE ABLE TO RESTART THE VEHICLE AND BEGAN TO 'LIMP HOME'. THE VEHICLE WAS NOT ABLE TO ACCELERATE AND WE EXPERIENCED 'OVER HEATING' WARNINGS ( IN RED ) AND HAD TO STOP THE VEHICLE TO COOL THE ENGINE. WE ARRANGED FOR MERCEDES BENZ ROADSIDE ASSISTANCE TO TOW THE VEHICLE TO THE KONA MERCEDES BENZ SERVICE CENTRE THE NEXT DAY. YELLOW ENGINE WARNING LIGHTS REMAINED ON WHEN THE VEHICLE WAS PLACED ON THE TOW VEHICLE.WE HAVE USED THE KONA SERVICE CENTRE SINCE IT WAS OPENED, THE TEAM LED BY PAULETTE GANTALA IS VERY CAPABLE AND THEY PERFORM EXCELLENT WORK. AFTER SEVERAL DAYS WE LEARNED THAT THE CAUSE OF THE MALFUNCTION WAS NOT FOUND AND WE WERE TOLD TO 'MONITOR THE SITUATION'. I ATTACHED THE SERVICE REPORT WHICH DESCRIBES THE EXTENSIVE INVESTIGATIVE WORK COMPLETED BY THE KONA MERCEDES SERVICE CENTRE. WE ARE VERY CONCERNED THIS MALFUNCTION IS A SAFETY RELATED ISSUE AND NEEDS TO BE ESCALATED. SUDDEN UNEXPECTED LOSS OF POWER CREATES EXTREMELY DANGEROUS SITUATIONS.

Mileage: 4,200

WHILE DRIVING THE VEHICLE, A SERIES OF ELECTRICAL SYSTEM WARNINGS WERE DISPLAYED IN RAPID SUCCESSION. SHORTLY THEREAFTER, THE VEHICLE LOST POWER, THE ENGINE SHUT OFF, AND THE VEHICLE BEGAN TO GLIDE. THIS INCIDENT OCCURRED ON A RESIDENTIAL STREET WHILE THE VEHICLE WAS TRAVELLING AT 25-30 MPH. THE WARNINGS WERE SPECIFIC TO THE 48V ELECTRICAL SYSTEM. THE VEHICLE WAS OPERABLE AFTER THE INCIDENT AND IT WAS DRIVEN TO THE DEALERSHIP. THE REPAIR INVOICE AND THE WARNING PICTURES ARE ATTACHED. THE ISSUE WAS TRACED TO A GROUNDING ISSUE AS MOST OF THE CONNECTIONS BETWEEN THE ELECTRICAL SYSTEM AND THE VEHICLE'S CHASSIS WERE INAPPROPRIATELY FILLED WITH PAINT (ASSUMED FROM THE VEHICLE ASSEMBLY PROCESS).

Mileage: 8,900