2022 Mercedes-Benz GLC 300 Problems

The vehicle has experienced two separate incidents of significant loss of power/acceleration. First incident – January 2024, Clarksville, TN: While driving downtown, the vehicle suddenly lost significant power and could not provide normal acceleration. The estimated remaining range was approximately 50 miles. The vehicle was subsequently inspected/serviced by Mercedes-Benz/dealer personnel, but the underlying cause was not conclusively identified or resolved. Second incident- [XXX] [XXX]: While driving in the first lane of [XXX], the vehicle suddenly lost significant power/acceleration when the estimated remaining range was approximately 75 miles. There were no warning alarms or messages before the loss of power. My wife and child were in the vehicle. The vehicle could not provide normal acceleration in highway traffic, creating an extremely dangerous situation. The incident nearly resulted in a serious traffic accident, and my wife had to take immediate action to help avoid a potential collision. The vehicle was subsequently inspected by Mercedes-Benz/dealer personnel, but the specific loss-of-power condition was not conclusively reproduced or confirmed under the circumstances in which it occurred, and the underlying cause was not identified or resolved. The vehicle has therefore experienced this type of serious power-loss condition twice despite service attempts. I can no longer safely drive or intentionally test the vehicle to reproduce this condition. Attempting to drive until approximately 75 miles of remaining range could cause another sudden loss of power and potentially result in a serious accident. I will not intentionally recreate a potentially dangerous failure on a public highway with my family or other motorists at risk. I am reporting this because unexpected loss of power while traveling on a highway presents a serious safety hazard and potential collision risk. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

After recalls performed trouble code P2402 EVAP leak still is present and check engine light is on

Loss of Steering Control at Highway Speeds – 2022 Mercedes-Benz GLC300 Vehicle: 2022 Mercedes-Benz GLC300, VIN [XXX] Dates of Incident: September 13th and October 4th Mileage at Time of Incident: 39,500 While driving on a four-lane expressway at highway speeds, my vehicle suddenly and completely lost steering control, resulting in a total inability to steer. First Incident The first event occurred during light rain with mildly wet road conditions. Without warning, the vehicle hydroplaned and violently crossed all four lanes approximately 20–25 times, narrowly avoiding collisions with other vehicles and medians. The steering wheel was completely unresponsive. After several minutes, the car inexplicably corrected its course. Second Incident The second incident occurred weeks later under clear, dry conditions with my minor child in the car. Once again, the steering wheel locked, leaving me unable to direct the vehicle. I had to physically force the wheel to prevent the car from leaving the highway. Investigation The car was towed to Mercedes-Benz of Coral Gables, where technicians were unable to find any fault despite multiple diagnostic attempts. I have since discovered that 2023 and 2024 models of this same vehicle are under active recall for a similar steering malfunction, which may indicate that 2022 models are also affected. Safety Concern This defect poses an imminent risk of fatal accidents, both to occupants and to other drivers. The failure occurs without warning, at high speeds, and results in total loss of steering control. Requested Action I request that the NHTSA investigate whether 2022 models should be included in the existing recall related to steering control failure in Mercedes-Benz vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I was driving home on a 4 Lane Expressway on a Saturday afternoon, it was mildly raining with the roads a little wet. I suddenly lost control of the car and could not control the steering wheel, the car ended up hydroplaning and I lost control it ping-ponged across four expressway lanes back-and-forth about 20 to 25 times with zero control of the steering wheel, barely missing the medians and other cars. It should have been a massive catastrophe. Cars around me you had to stop and swerve around me to avoid hitting me all while driving on the expressway. Had someone accidentally hit me in the process it would’ve certainly flipped the car and I would’ve either ended up dead or in the ICU. After several minutes somehow without moving the steering wheel, I managed to just go straight and pull over. And waited for help to get back safely slowly. I thought the incident was isolated because the roads might have been the cause. But I went out out of the country and upon coming back, drove my car again on the expressway coming back home and the exact same thing happened with my minor child in the car across two expressway lanes in the evening time With the roads perfectly dry. Lost control of the steering wheel could not steer or direct the car and had to jerk it from to prevent it from driving off the highway. It seemed to have occurred both times at a higher velocity on expressways when the steering wheel needed to be engaged. I had it towed to the Mercedes Benz Of Coral Gables dealership, but they cannot find anything wrong with the car, even though the exact same model of my car has an active recall for 2023 and 2024 models. For the same problem, I later learned. Mine is a 2022. I have been in a loaner vehicle for three weeks while they investigate and I need Assistance to make sure that something gets done because nothing has been found and I do not want to risk driving with my child in the car.

Vehicle: 2022 Mercedes-Benz GLC 300 4MATIC Component: Electronic Parking Brake (EPB) / Service Brakes Summary of Complaint: This vehicle has an ongoing, unresolved Electronic Parking Brake (EPB) defect. The amber EPB warning light has recurred multiple times, including most recently after a $3,000 dealership repair intended to correct this exact fault. Timeline: 1.Following a brake pad replacement, the vehicle experienced an EPB failure, brake fluid loss, and a gear shift interlock lockout — leaving the vehicle inoperable. 2.The vehicle was taken to a Mercedes-Benz dealership for repair. This resulted in a dispute over unauthorized work performed and a request for goodwill coverage tied to a known Mercedes-Benz EPB recall. 3.I paid approximately $3,000 to the dealership for a repair specifically to resolve the EPB fault. 4.Approximately a few weeks after this paid repair, the same amber EPB warning light returned, indicating the underlying defect was not resolved. Safety Concern: The EPB is a safety-critical system. Repeated, unresolved failure of this system — including a prior incident involving brake fluid loss and a gear shift interlock lockout that left the vehicle inoperable — represents a real risk of parking brake failure and loss of vehicle control/immobilization in normal use. Additional Notes: •This defect appears connected to a known Mercedes-Benz EPB recall. •I have photo documentation of the recurring warning light (dated) and the dealership repair invoice for the $3,000 repair. •I have an open case with Mercedes-Benz Customer Assistance regarding this issue.

While driving down a busy neighborhood street 2 lanes with cars on both sides making it a 1 lane road pulled over to the side a little to let cars pass. All of a sudden ALL electrical and engine stopped and turned off. Only thing that was powered was instrument cluster with multiple warnings like SRS Malfunction, Steering Malfunction, SOS Inoperative, Parking Brake and more. We believe the car had also shifted to park on its own. No power to anything not even hazard lights. Nothing electrical had any sort of power. Could not even turn car off completely could not get the instrument cluster to turn off with ignition button. When I say everything electrical had no power I mean everything except instrument cluster. Hazard lights power locks, lights of any kind, ignition switch, gear selector, windows, sos feature, nothing had power. I could not imagine having this issue driving on the interstate and having the car completely loose ALL electrical power and what could happen to specially with a SRS malfunction and issue with steering. Had to have a wrecker come with wheel dollys because car could not be put in neutral and towed to Mercedes dealer. Upon their inspection they found the Circuit 30T relay to be stuck in the open position which killed power to everything so the technician replaced the engine compartment pre-fuse panel. It is such a unsafe and very hazardous issue to have a relay failure to where all power is lost especially if you were driving on interstate especially at night with traffic to loose everything electrical even hazard lights and headlights, SRS maltunction, Steering. Mercedes needs to figure this very unsafe issue out.

My 2022 Mercedes-Benz GLC 300 experienced a significant cooling-system malfunction involving repeated low-coolant warnings, engine overheating, and substantial coolant leakage. Approximately two weeks before the overheating incident, the vehicle began displaying low-coolant warnings. On October 22, 2026, after driving normally and stopping to refuel, I restarted the vehicle. Approximately five minutes later, the dashboard displayed a red warning stating, "Coolant Too Hot. Stop Vehicle. Turn Engine Off." The engine temperature gauge approached the maximum range. I immediately sought a safe location to stop and turned off the engine within approximately one minute of the warning. After allowing the vehicle to cool, I discovered the coolant reservoir was nearly empty. I replenished the coolant, and the warning temporarily disappeared. However, following limited additional driving, the low-coolant warning returned. I subsequently observed substantial coolant leaking beneath the vehicle while it was parked with the engine turned off. The leakage appeared in multiple locations underneath the front and center portions of the vehicle. I documented intermittent dripping followed by sudden streams of fluid, resulting in several visible puddles. This malfunction presents a safety concern because the vehicle experienced rapid overheating during normal operation, requiring an immediate stop to avoid possible engine damage or loss of vehicle operation in traffic. The specific failed component has not yet been identified. The vehicle has not yet undergone a professional diagnostic inspection, but the symptoms and external leakage have been documented through photographs. The vehicle is available for inspection. I am requesting that NHTSA investigate whether this cooling-system failure represents a broader safety concern affecting similarly equipped Mercedes-Benz vehicles.

My 2022 Mercedes-Benz GLC 300 (17,700 total miles) suffered a catastrophic structural engine block failure and an explosive loss of propulsion while driving at highway speeds. This occurred exactly 6 days and 183 miles after a franchised Mercedes-Benz dealership performed the official fuel pump impeller safety recall (NHTSA Campaign 23V-445).The dealership's official repair invoice documents that the technician custom-modified the recall remedy by reusing parts, explicitly stating: 'Relocated floater from old pump onto new fuel pump.' Simultaneously with the mechanical engine failure, a 'Reduce Engine Oil Level' message flashed on the dashboard, indicating severe fuel dilution from the compromised fuel system.The dealership is actively violating federal recall mandates by refusing to investigate this failed safety remedy unless I sign an open-ended financial check for a diagnostic and teardown fee. They have also revoked my substitute transportation to coerce payment. Mercedes-Benz USA Corporate Case Number 23652724 has been opened. I am requesting a federal safety investigation into this dealer's non-compliant recall remedy execution."

I have experienced 4 incidents of the car accelerating on its own. I have taken it to the dealership twice and they are unable to reproduce the problem. Problems began occurring in 2025 and occurred again this past week (August 20246). In the most recent incident I was accelerating on an "on ramp". The car suddenly took hold and continued to speed up despite my foot not being on the gas. I had to drive the car to safety with my foot on the break. The moment I took my foot off the break it would speed up. The floor mat was not touching the gas in all of the instances of this occurring. The gas pedal was not stuck to anything. I nearly avoided a serious accident as where i was trying to merge was running out of a lane and a cement block was in front of me. I was also with an infant and 2 year old in my car. There have been no warning messages when this occurs.

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.

See attached document for complaint.

The contact owns a 2022 Mercedes-Benz GLC300. The contact stated that while driving 60 MPH, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that there were several unknown warning lights illuminated before the engine seized. The vehicle was restarted; however, while driving at an undisclosed speed, the failure reoccurred. The contact started the vehicle again, and the vehicle was slowly driven to the residence. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 51,519.

Vehicle: 2022 Mercedes-Benz GLC 300 4MATIC Component: Electronic Parking Brake (EPB) / Service Brakes Summary of Complaint: This vehicle has an ongoing, unresolved Electronic Parking Brake (EPB) defect. The amber EPB warning light has recurred multiple times, including most recently after a $3,000 dealership repair intended to correct this exact fault. Timeline: 1.Following a brake pad replacement, the vehicle experienced an EPB failure, brake fluid loss, and a gear shift interlock lockout — leaving the vehicle inoperable. 2.The vehicle was taken to a Mercedes-Benz dealership for repair. This resulted in a dispute over unauthorized work performed and a request for goodwill coverage tied to a known Mercedes-Benz EPB recall. 3.I paid approximately $3,000 to the dealership for a repair specifically to resolve the EPB fault. 4.Approximately a few weeks after this paid repair, the same amber EPB warning light returned, indicating the underlying defect was not resolved. Safety Concern: The EPB is a safety-critical system. Repeated, unresolved failure of this system — including a prior incident involving brake fluid loss and a gear shift interlock lockout that left the vehicle inoperable — represents a real risk of parking brake failure and loss of vehicle control/immobilization in normal use. Additional Notes: •This defect appears connected to a known Mercedes-Benz EPB recall. •I have photo documentation of the recurring warning light (dated) and the dealership repair invoice for the $3,000 repair. •I have an open case with Mercedes-Benz Customer Assistance regarding this issue.

While driving down a busy neighborhood street 2 lanes with cars on both sides making it a 1 lane road pulled over to the side a little to let cars pass. All of a sudden ALL electrical and engine stopped and turned off. Only thing that was powered was instrument cluster with multiple warnings like SRS Malfunction, Steering Malfunction, SOS Inoperative, Parking Brake and more. We believe the car had also shifted to park on its own. No power to anything not even hazard lights. Nothing electrical had any sort of power. Could not even turn car off completely could not get the instrument cluster to turn off with ignition button. When I say everything electrical had no power I mean everything except instrument cluster. Hazard lights power locks, lights of any kind, ignition switch, gear selector, windows, sos feature, nothing had power. I could not imagine having this issue driving on the interstate and having the car completely loose ALL electrical power and what could happen to specially with a SRS malfunction and issue with steering. Had to have a wrecker come with wheel dollys because car could not be put in neutral and towed to Mercedes dealer. Upon their inspection they found the Circuit 30T relay to be stuck in the open position which killed power to everything so the technician replaced the engine compartment pre-fuse panel. It is such a unsafe and very hazardous issue to have a relay failure to where all power is lost especially if you were driving on interstate especially at night with traffic to loose everything electrical even hazard lights and headlights, SRS maltunction, Steering. Mercedes needs to figure this very unsafe issue out.

The contact owns a 2022 Mercedes-Benz GLC300. The contact stated that while driving at 65 MPH, the sunroof exploded. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 56,000.

Since I purchased this vehicle 2.5 months ago, the windshield wipers started chattering/making noise and not working properly after about 2 days. I brought the car in and the dealership replaced the wipers. The chattering started again shortly after, then the dealership polished the windshield. It worked well for about 2-3 weeks and now the wipers are starting to streak and chatter again. I have a third appointment to have the windshield re-polished and wipers replaced, again. I have no faith this will fix the issue since its been done before. I see that this is a common issue with this brand/model.

Vehicle vibrates quite violently when hit some potholes. Steering wheel is the part that vibrates more but vibration is felt throughout the vehicle. It is more prevalent at highway between 55-65 mph speed. I also noticed that car shakes unusually and tilts to one side at times making it quite uncomfortable for driver. back tires make slipping noice on potholes and feels like car is going to be unstable momentarily . All these issues are putting driver and others at risk. I joined Facebook page of glc300 owners and almost everyone reported this kind of problem. For most of the people including me , it is still unresolved . I took my vehicle to dealer and they updated software but issue still persists.

When driving at 40 to 60 MPH and hit shallow pot hole or bump in the road the front wheels violently shake and the steering wheel (electric steering) violently vibrates for 5 to 8 seconds. Dealer checked the vehicle and claims there is nothing wrong with it but did turn off the "attention assist" setting from sensitive setting claiming it was the cause. The issue still exists but not as violent. I'm concerned of loosing control of the car/my safety. FYI: never experienced this issue with my previous car (same car two years older ,2020 GLC 300).

I am reporting a potentially serious vehicle safety issue involving a 2022 Mercedes-Benz GLC after a fatal crash. I was seated in the left rear seat. One occupant died and multiple people were injured. According to the Florida Highway Patrol crash report, the left curtain air bag was listed as “Equipped; Not Deployed,” while the right curtain air bag was listed as “Equipped; Operative; Deployed.” I suffered serious injuries while seated on the same side where the curtain air bag did not deploy. Before the crash, I remember hearing an unusual metallic rattling/clanking noise from the vehicle. I do not know what caused the noise or whether it contributed to the crash, but it occurred before impact. A family member later reported this pre-crash noise to the vehicle’s insurer. Law enforcement indicated that the vehicle’s event data recorder (EDR/“black box”) would be downloaded, but the crash report later stated “EDR Downloaded: No.” To my knowledge, the EDR data was never retrieved or preserved. The insurer later sold the vehicle as salvage before I was able to arrange an independent defect inspection, so the vehicle is no longer available to me for examination. I am not claiming that a defect has been proven. I am asking NHTSA to review whether the documented left-curtain nondeployment, in a crash severe enough to cause a fatality and multiple injuries while the opposite curtain air bag deployed, warrants investigation of the air bag/restraint system or another vehicle component. I am also asking NHTSA to consider the pre-crash metallic noise and the loss of access to the vehicle and EDR data when evaluating this complaint. Because the vehicle and EDR evidence may no longer be recoverable, I respectfully ask NHTSA to evaluate this complaint promptly and compare it with any similar air bag, restraint-system, sensor, or electrical complaints involving this model.

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.

When driving at 40 to 60 MPH and hit shallow pot hole or bump in the road the front wheels violently shake and the steering wheel (electric steering) violently vibrates for 5 to 8 seconds. Dealer checked the vehicle and claims there is nothing wrong with it but did turn off the "attention assist" setting from sensitive setting claiming it was the cause. The issue still exists but not as violent. I'm concerned of loosing control of the car/my safety. FYI: never experienced this issue with my previous car (same car two years older ,2020 GLC 300).