Collision Avoidance complaints by model year
Which parts fail
Components named in complaints (automatic emergency braking, adaptive cruise, lane keeping, backup camera).
Mileage when the problem started
What owners report
The contact owns a 2025 Mercedes-Benz GLC300. The contact stated that while driving approximately 30 MPH, there was an abnormal grinding sound coming from the vehicle. The contact stated that the brake assist suddenly activated and the vehicle came to an abrupt stop, causing the seat belt to immediately retract and lock. The contact was slightly jerked from the abrupt stop. The contact stated that a warning light with a red triangle with an image of a crash in the center was illuminated. The contact stated that after starting the vehicle, the infotainment center and the instrument panel were completely black. The vehicle was restarted several times before both systems started operating as needed. …
The brakes did not function at all. Upon trying to brake, the brake pedal was hard and the car would not stop. The car went into s storefront where the cashier is located and could have resulted in serious injury or death to anyone waiting to pay at the store. The forward collision alarm did not sound, the dashboard indicator for an impending forward collision did not illuminated. The car did not slow down or stop to avoid the collision. The car is currently at the body shop.
The contact owns a 2024 Mercedes-Benz GLC 300. The contact stated that while driving at approximately 35 MPH, the brake was applied unexpectedly without the contact depressing the brake pedal. The contact stated that she was unsure if the forward collision system was turned on at that time. The driver's seat belt tightened, and she sustained a bruise on her left arm and soreness on her chest. Medical attention was required. The vehicle was taken to a dealer where they were not able to replicate the failure. On another occasion, while parked, the tailgate was opened as groceries were being loaded into the rear cargo area. The tailgate closed inadvertently and struck the contact's head. The contact sustained head and neck injuries, and medical attention was required. The vehicle was taken to a dealer where the failure was not able to be replicated. …
My 2024 Mercedes-Benz GLC 300 has experienced multiple serious safety-related malfunctions involving several vehicle systems. In August, after picking up the vehicle from service, I placed my [redacted] grandson in his car seat, set my purse with the key inside the vehicle, and closed the rear door. The vehicle immediately locked all doors on its own, trapping my grandson inside in approximately 88-degree temperatures. I was unable to gain access for about 30 minutes. This created a dangerous child safety situation. Key fob periodically will lock you out of car. The following day, while driving approximately 35 mph with my [redacted] grandson in the vehicle, the car suddenly and violently applied the brakes and tightened the seatbelt without warning or any obstacle present. The vehicle came to a complete stop in the roadway. …
The contact owns a 2023 Mercedes-Benz GLC 300. The contact stated while driving on an access road at 35 MPH, the brake pedal was not depressed; however, the vehicle came to an immediate stop. There were no warning lights illuminated. The contact restarted the vehicle and was able to continue driving normally. The local dealer was contacted and sent a tow truck to pick up the vehicle from the residence for diagnostic testing. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 12,000.
On [redacted], I was driving at 45MPH on a two-lane state road. There was no traffic within 1/4 -1/2 mile of me on that road. There were no guardrails and the road was clear - no birds, animals, people, or construction. For no reason, the car beeped twice and automatically slammed on the brakes so forceful that everything on a seat landed on the floor. Had there been a vehicle behind me, they would have almost certainly slammed into me. This is my second safety report with this vehicle, the previously reported lane keeping assist still allows me to depart my lane with no correction or indication by the system, the dashboard indicators remain green if I depart my lane without a turn signal. It has been in 5 times for this and Mercedes closed the case. They say it's fine. …
I was involved in a severe front-end collision where my vehicle struck another vehicle with significant force. Despite the major impact, the front airbags did NOT deploy. The entire front end of the vehicle was crushed, including destruction of the radiator, damage to engine components, internal structural collapse, and leaking fluids. Based on the severity and direct frontal nature of the crash, airbags should have deployed but did not. As a result of the impact, I sustained a neck and upper shoulder injury and required medical evaluation. There were no warning lights or messages prior to the crash indicating any malfunction in the airbag or SRS system. The vehicle is available for inspection by NHTSA, the manufacturer, insurance, or an authorized Mercedes-Benz service center. This appears to be a possible failure of the airbag/SRS system during a qualifying collision.
The contact owns a 2022 Mercedes-Benz GLC300. The contact stated while driving 65 MPH, the Distance Assist Distronic engaged and the vehicle slowed down abruptly. The contact immediately disengaged the Distance Assist Distronic and resumed driving. The vehicle was taken to an unknown dealer where he was informed that the vehicle operated as designed. The dealer disabled the Distance Assist Distronic; however, the system reengaged while driving. The vehicle was taken to a second dealer who disabled the feature; however, the failure recurred while driving. The manufacturer was notified of the failure and a case was opened. The vehicle was not diagnosed or repaired. The failure mileage was approximately 1,500.
Related recalls (2)
Back over prevention › Display function
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018-2021 CLA-Class, GLE/GLS-Class, A-Class, C-Class, E-Class, E-Class Coupe/Convertible, GLA/GLB-Class, GLC-Class, and CLS-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details.
Remedy: Dealers will update the rearview camera software, free of charge. Owner notification letters were mailed July 15, 2022. Owners may contact MBUSA customer service at 1-800-367-6372.
Forward collision avoidance › Sensing system › Radar
Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2019 C300 Cabrio, C300A Cabrio 4MATIC, C300 Coupe, C300 Coupe 4MATIC, C300, C300 4MATIC, C43 AMG Cabrio 4MATIC, C43 AMG Coupe 4MATIC, C43 AMG 4MATIC, C63 AMG Cabrio, C63S AMG Cabrio, C63 AMG Coupe, C63S AMG Coupe, C63 AMG, C63S AMG, CLS450, CLS450 4MATIC, CLS53 AMG 4MATIC,…
Remedy: MBUSA will notify owners, and dealers will update the radar sensor control unit software, free of charge. The recall began September 13, 2019. Owners may contact MBUSA customer service at 1-800-367-6372.
Frequently asked questions
Which Mercedes-Benz GLC300 years have collision avoidance problems?
By NHTSA complaints, the 2020 (13), 2023 (13), 2024 (8), 2021 (7) and 2018 (5) model years. Collision Avoidance complaints make up 19% of all complaints for the 2020.
Is there a recall for Mercedes-Benz GLC300 collision avoidance problems?
Yes — 2 recalls, including 22V-232 (display function, Apr 8, 2022); 19V-540 (radar, Jul 19, 2019). Recall repairs are free at authorized dealers; check a specific car with the VIN recall check.
At what mileage do Mercedes-Benz GLC300 collision avoidance problems start?
Across all years, half of the complaints with a recorded mileage happened before about 55,000 miles; 73% happened before 50,000 miles.
What part fails most often?
Owners most often name the automatic emergency braking (26 mentions), followed by the warnings (11).
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.