2024 MERCEDES-BENZ GLC 300 Complaints

While carrying my carbon fiber bicycle on a rear hitch mounted bicycle carrier, the vehicle severely and violently applies the brakes and swerves either left or right or both. This catastrophic maneuver has put me and other drivers in a non avoidable highly calamity. This “AUTO” maneuver happens dozens of times in during a fifteen mile trip to local bicycle trails. Dealer replaced the Trailer Recognition Module 9-24-2025. As expected, dangerous situation remains. Happens every opportunity when carrying bicycles. First exhibited after purchase 6-29-2024 to current.

•Incident Details: •Both sudden shutdown incidents •“12V Battery” warning (first incident) •“Stop - Switch Off Vehicle” warning (second incident) •That it happened with children in the car on a tollway Safety Concerns: •Loss of power steering/braking •Risk of collision •Repeated failures on a 1-year-old vehicle

I am writing to report a critical safety issue with my 2024 Mercedes-Benz GLC300, VIN: [XXX] , which I purchased on [XXX], from Mercedes-Benz of Walnut Creek, CA, with 9,500 miles. On [XXX], while driving on [XXX], the vehicle suddenly lost power, the transmission downshifted to 2nd gear, and the accelerator became unresponsive. I was forced to drive at 20 mph for 20 minutes on a busy freeway, posing a severe risk of a rear-end collision. I managed to exit the freeway, but this incident could have resulted in a serious accident. This failure may be related to prior recalls of the 2024 GLC300, including issues with a defective 80-amp fuse (February 2024) and a loose 48-volt battery ground connection (March 2024), both of which can cause power loss. I urge the NHTSA to investigate this incident to determine if it warrants an expanded recall or further action to protect other drivers. I have notified Mercedes-Benz of Walnut Creek CA and Mercedes-Benz USA, demanding an investigation and a refund under the California Lemon Law. Please confirm receipt of this complaint and provide an update on any investigation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I am experiencing auto braking when there are no obstructions near or around the vehicle. The auto braking is random but occurs fairly often. It is very unsettling and makes me very nervous while driving my brand new vehicle. This happens without warning and can definitely put myself and my passengers as well as passengers in the vehicles around me at great risks of collisions.

Attention Assist System Suspended notification comes on randomly on vehicle while driving, rendering driver defenseless with regard to safety warnings that would otherwise be in effect, such as blind spot assist, attention assist, which are vital components for safe driving. This has happened on numerous occasions, most recently on 12/06/2024 while driving under destination route guidance. It has also happened when car was stopped to retrieve mail at residence mail box and, at other times for no apparent reason, while driving. Each time when engine was restarted the dashboard read 'System suspended' and continued to do so until car was returned to dealer. This vehicle was purchased on 12/21/2023 and with less than 350 miles began repeated problems with warnings, the first of which was "Check engine"on 02/02/2024, as car was running rough. Car was repaired(dealer determined cause was electrical/software error, fault code) yet before driving out of the dealership the same 'check engine' warning reappeared and vehicle had to be returned to service that same day for the same problem. Since that date in 2023, this vehicle has had numerous seemingly computer related issues that render it unreliable as to the safety devices this vehicle features that should always be maintained. On 03/21/2024 with less than 950 miles the fans remained running after shutting vehicle off and a message appeared stating" cooling system malfunction/reduced drive performance" with a red triangle on dashboard. Dealer determined the cause was 'SOFTWARE" At this point I am concerned that this vehicle is over engineered with computerized options that randomly fail. On another occasion the lights on one side may have been on overnight. The lights (courtesy lights) were on on the right side overnight in garage. My safety is continuously at risk whenever a warning appears.I replaced my GLK specifically to have Blind Spot Assist, PRE-safe, Attention Assist, Active distance assist and other features.

When stopped at a light or stop sign, Vehicle will Jerk forward as If hit from behind. Very surprising and dangerous. Very intermittent. The has happened many times. Vehicle will at times have rough downshifts. Ie. overdrive (9th) to (8th) gear. also intermittent. This has happened multiple times. Vehicle was taken to the dealer twice for a total of 50 hours in the shop. The first service time no problem was found, diagnostics did not show problem. Aug 22 to Aug 30, 2024. The second service time Oct 3 to Nov 14, 2024. Problem was duplicated by the technician. Vehicle diagnostics still did not show a problem. Technician replaced the transmission valve body, did various software checks at the request of the factory. The engine control unit was then changed based on data supplied to the factory. At this point technician checked the car and dealers believes car is fixed. Vehicle has been returned to us on Nov 14 2024. We have requested the vehicle be bought back or replaced.

The reverse sensors are faulty, causing the GLC300 model to randomly auto-brake while going in reverse. My driveway is flat and long with no significant grade changes and this has occurred at another location as well with similar topography. There are no obstructions present nor any significant grade changes, the vehicle auto-brakes not everytime, happens out of the blue once every 8-12 tries. My new vehicle has been checked out by Mercedes-Benz of Cary service department 2 times, since buying new April 2024. They brought my car out to my house themselves and experienced the auto-braking first hand. They brought out a second GLC300 and it auto-braked as well. The technicians have calibrated, and updated the sensors to no avail. My driveway is long and flat with a slight slope at the end, but it happened to me at my friends house who's driveway is all flat. This is a serious safety risk for me and all passengers. It makes everyone tense not knowing next time it may happen. No matter the revering speed, or if you keep your foot on brake lightly as you are backing up, the glc300 randomly will auto-brake without any warning lights or sounds. The tires screech, it locks up in an instant. It is frightening and we are scared to anticipate the next occurrence or risk bruising our body or head injury. Even when I manually over-ride the rear and/or surrounding sensors, turning them off temporarily as I back up in reverse- the car will still auto-brake. Mercedes has yet to agree with me that this is a safety issue and on 11/8 asked me to pick up the car. I refused until the issue is fixed. They still have my car in service, it has been 3 weeks since 10/18/24. This was the 2nd time I brought in in for this issue since I bought new March 30 2024. I called corporate to ask them to buy back the car if the issue cannot be fixed, they have yet to respond.

Passenger backseat seatbelt would not release under any circumstance. I tried turning the car off and on again. Checking settings on the screen and even releasing the seat a bit. Pushing the red button on the buckle did nothing. Pulling did nothing. Eventually had to cut the seatbelt to get the passenger out. And it is still stuck in the buckle.

OUR SUV IS 6 WEEKS NEW AND WAS PURCHASED NEW AT THE MERCEDES DEALERSHIP. REAR HATCH: WHEN STANDING BEHIND VEHICLE REAR DOOR HATCH CLOSES RANDOMLY WITH NO WARNING OR BEEP. CLOSES VERY QUICKLY AND HITS HEAD VERY HARD. FEET ARE NOT NEAR THE BUMBER WHICH ELIMINATES THE REAR FOOT ACTION THAT CLOSES THE HATCH. WHEN THE HATCH HITS YOUR HEAD IT COULD KNOCK YOU OUT ESPECIALLY IF YOUR EDERLY OR A CHILD. ALSO IF YOU TRY AND STOP THE HATCH COSING ITS VERY STRONG AND TAKES A LOT OF STRENGTH. WHEN YOU USE THE REMOTE OR BUTTON IN CAR TO OPEN HATCH IT OPENS SO FAST AND BEEPS TO LATE TO ALERT DOOR IS OPENING. VERY DANGEROUS. THIS PROBLEM HAPPEN SEVERAL TIMES AND IS RANDOM. THE LAST TIME IT HAPPEN WAS SUNDAY 9-1-24 WHILE LOADING GROCERIES AT COSTCO

The contact owns a 2024 Mercedes Benz GLC 300. The contact stated that while attempting to park, the vehicle experienced unintended acceleration causing the contact to lose control of the vehicle and crash into a wall, another vehicle, and two poles where it came to stop when crashing into the second pole. During the unintended acceleration, the contact depressed the brake pedal to control the vehicle however it failed to respond. No air bags deployed. The contact sustained chest, neck, and back injuries and an ambulance transported her to a hospital. A police report was filed. The vehicle was towed to an independent mechanic by the insurance company. The vehicle was not repaired. The dealer was not contacted. The manufacturer was not made aware of the failure. The failure mileage was approximately 97,000.