2024 Mercedes-Benz GLC 300: check engine light

Filed Jun 3, 2026 · Engine · AL

While driving the vehicle the engine started running rough, check engine light illuminated and it would not accelerate above 40 mph. There are 29,100 miles on the vehicle, it's been serviced on schedule by Mercedes and is owned by me since new. It is especially concerning due to the acceleration topic which could have been catastrophic if I were trying to merge into traffic. Dealer service say the camshaft bearing needs to be replaced. It seems this is very premature for the mileage on the vehicle.

Filed Dec 9, 2024 · Engine, Lights · PA

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.

Filed Mar 20, 2024 · Electrical · 2,174 miles · CA

The contact owns a 2024 Mercedes-Benz GLC300. The contact stated that while driving at an undisclosed speed, the audible alarm activated and several warning lights illuminated. The contact stated that all the warning lights went off except the check engine and the low-battery warning lights. The vehicle was taken to the dealer. The vehicle had not been diagnosed or repaired. The contact stated that the vehicle was previously taken to the dealer on three occasions because of electrical or software failure. The manufacturer was made aware of the failure and a case was filed. The failure mileage was approximately 2,174.

Filed Mar 1, 2024 · Electrical, Engine · IL

Check engine light appears, also a blue engine and a turtle. The dealer is aware, they have had it 3times for the same issue and this time 23 days and counting. Currently Mercedes has no fix. I purchased the veh 30 Nov 23- first appeared 16 dec and continued going on and off.

Filed Jan 19, 2024 · Electrical · 1,800 miles · MN

The contact owns a 2024 Mercedes-Benz GLC300. The contact stated that upon starting the vehicle, the check engine warning light illuminated. The vehicle was taken to a dealer and the contact was informed that the 48V bolt battery had caused the check engine warning light to illuminate. The contact was informed by the dealer that the temporary fix would be to reduce the battery charge to 25% then charge the battery to 75%. The check engine warning light returned soon after the fix and the contact was informed that there was no permanent fix for the defect. The manufacturer had yet to be notified of the failure. The vehicle had yet to be repaired. The failure mileage was approximately 1,800.

Filed Jan 19, 2024 · Engine · IL

Brand new 2024 GLC300 4MATIC with less than 750 miles. Check Engine light came on with no error message explanation. Brought it in to dealer for service - Found fault code POA7F00. Dealer followed LI54.10-P-077250. Cleared codes. Check engine light is still on with no resolution to problem at this time. Was told to ignore and keep driving. Driving with check engine light illuminated is a safety concern for me.

Filed Jan 17, 2024 · Electrical, Transmission · MN

Brand new '24 GLC300 4MATIC. Engine light came on with no error message. Brought it in for service. Miscellaneous engine repair states: "Found current code POA7F00 in drivetrain control unit. Followed LI54.10-P-077250. Cleared codes. Drained 48V battery to below 25% SOC. Charged vehicle to 70% SOC. Job complete." Service foreman mentioned that the service performed may not resolve issue. He contacted Mercedes-Benz Engineering and said no fix at this time and no ETA. Left service with no more engine light on. However, it didn't take long, and the engine light came on again. I called service again, and I was asked to take the car back in to be sure it is not anything else. Took my vehicle back, and service foreman diagnosed the issue. Code is the same as before with issues on the 48V battery. Service foreman is unsure of the exact issue. Mercedes-Benz Engineering did not provide details of the problem. I believe this issue poses a safety risk without knowing for sure what is the real cause and what might be the effects on the vehicle. This GLC is my family daily use, and it has become a big safety concern on the road. Service was very helpful and accommodating with my vehicle's issues. Unfortunately, fix is unknown from Mercedes-Benz to be able to resolve. I have also called the Mercedes-Benz Customer Care, 800‑367‑6372. Unfortunately, there is nothing they can do. I've asked to open a case. Case # [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)