2023 Mercedes-Benz GLC 300 electrical problems

Filed Mar 19, 2026 · Electrical · 12,000 miles · CA

The contact owns a 2023 Mercedes-Benz GLC300. The contact stated that while driving at an undisclosed speed, the speed limit warning system failed to function as intended. The contact stated that while driving 60 MPH, the Heads-up Display (HUD) illuminated a red light and an unknown message about driving too slowly was displayed. The contact stated that the red light illuminated and flashed intermittently. The vehicle was taken to the dealer, and the contact was informed that the failure was common with the vehicle. The vehicle was not repaired. The contact stated that the failure persisted. The contact asked if the speed limit warning system could be deactivated, and the dealer was informed that it had to be approved by the manufacturer. The manufacturer was made aware of the failure. The contact was referred to the dealer for assistance. The contact stated that the dealer and the manufacturer offered no assistance. The failure mileage was approximately 12,000.

Filed Mar 18, 2026 · Driver assistance, Electrical · AZ

There are two issues 1) Unsure of the exact date, but about a year or two ago we were driving our car and the car's automatic break system went into effect on a typically busy, 3 lane road despite there not being any cars in front of our vehicle. We took it into the dealership, who confirmed the issue and told us that sometimes the automatic brake mis-identifies the metal plates in the roads to be vehicles. Had there been a car driving behind us at the time this was happening, it could have been a major accident as the speed limit on that road was 45mph. Additionally we had our [XXX] in the car. There were no warning lamps, messages or symptoms of the problem prior to failure. 2) Recently we have been having a warning sign on our car that says the 12v battery is low, even though it should not be. Historically this would tell us to drive our car around so the battery wouldn't die, but this would sometimes turn on even after a 30+ minute drive. It was turning on every single time we turned the car off, so we brought it into the shop. While in the shop, the dealer provided us with a brand new GLC 300. I took this GLC 300 to my son's daycare to drop him off and when I returned to the car I received an error message "48V battery service required" and could not turn on the vehicle. This brand new vehicle left me stranded. While I was safe at my son's daycare, this has caused me to have significant concerns around the safety and reliability of these GLC300s. We are planning on taking our 2023 GLC 300 on a 6 hour road trip with our [XXX] old and [XXX] old and I am very concerned about the car not starting if we stop for gas. What if we get stranded in a small city along the way? INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Mar 5, 2026 · Electrical · AR

I purchased a brand new GLC 300 on May 25, 2023. By June 2, 2023 I was already stranded due to a 12V battery electrical system failure. Since then I have been stranded 8 total times and the vehicle has been in the service department 14+ times for repeated electrical issues (8 of those visits were related to the same 12V battery electrical system failures. The battery was reportedly replaced in 2024-shortly thereafter I began experiencing issues with the collision assist malfunctioning. The alarms would sound seat belt tighten and brakes lock up while driving on the interstate. The theft deterrent alarm wound sound in the middle of the night without provocation. The panoramic roof would malfunction. The air vent disintegrated. In August 2025, the collision assist malfunctioned causing the vehicle to steer off the road resulting in a blow out. It has not been driven since.

Filed Dec 10, 2024 · Electrical · MI

check engine light continues to turn on and off, response from dealer maintenance is this issue is temperature related and just keep driving, not sure how this makes for an effective or safe functioning of a warning light also seems like it can lead to unnecessary trips to and costs at the maintenance garage. This has been a multiple time issue since purchase of vehicle.

Filed Oct 6, 2024 · Brakes, Driver assistance · AL

GLC 300 was purchased new on May 25, 2023. Multiple 12V battery errors, check engine indicators, and rear hatch closing on owner starting the first week of ownership. 48V battery and Main Fuse Box were replaced. Multiple recalls were addressed. Most significant issue related to false collision avoidance incidents on two occasions that resulted in dangerous situations and extreme stress on the occupants. First occurrence was on July 12, 2024. Driving approximately 40 mph on two lane road near a school that was not in session. There were no surrounding vehicles, pedestrians or obstacles. Vehicle beeped, seatbelts locked, and speed forced to 10 mph. Took vehicle to local MB dealership who attributed the vehicle’s response to proximity to a school zone. Vehicle was not checked for fault codes. Second occurrence was on August 19, 2024. Driving 55 mph on major highway and a truck entered the merge lane to the right. The truck was travelling at reduced speed and remained in the merge lane showing no effort to merge into vehicle’s lane. Vehicle had violent sudden deceleration with beeping alerts, locking seatbelts and reduced speed to 10 mph. Driver and passenger experienced symptoms of whiplash. It was fortunate that there was no vehicle travelling immediately behind the vehicle. Vehicle was driven to MB dealership for analysis. The vehicle had been driven 6,177 miles in 15 months. Service manager indicated there were no fault codes so no maintenance was warranted. Owner viewed the vehicle as dangerous due to false collision avoidance issues that put passengers and others at risk. The owner sold the vehicle to the MB dealership.

Filed Sep 20, 2024 · Electrical · WV

The care sends a message that the battery is low. Then the check engine light comes on till we drive the car for awhile. The first time this happened I took it to the dealer and they said they could find nothing wrong with it and was giving no readings. It has continued to happen a lot. The battery should not be going down if it not being used. There has to be a problem. This has been going on for over a year. The dealer where we bought the car called today about service and said there was a recall about the battery, but when I call MB they said there was not recall?

Filed Sep 17, 2024 · Electrical, Fuel system · WA · crash

Loss of propulsion at highway speeds with subsequent failure of digital light system at night resulting in injury crash

Filed Aug 19, 2024 · Electrical, Lights · TX

Second time the rear left tail light not working properly. The parking light stay on after turning vehicle off at time it turns off. The light assembly was replaced by dealership less than a year ago. The light assembly was defective according to the dealership vehicle was purchase 10 prior.

Filed Aug 12, 2024 · Electrical · 7,000 miles · TX · crash

The contact owns a 2023 Mercedes-Benz GLC 300 W4. The contact stated that when his wife was parking the vehicle at approximately 5 MPH and when she depressed the brake pedal, the vehicle stalled. The contact stated that his wife said that the brake pedal failed, and the instrument cluster was black. The contact stated that his wife had observed that the brake warning had been illuminated before the instrument cluster failure. The contact stated that his wife jumped the curb and crashed into the wall of a building. The contact stated that the front end of the vehicle was crushed, and the hood was damaged. The contact stated that the front headlights and front bumper were also crushed. The contact stated that the windshield was cracked as well. The contact stated that his wife was unhurt despite the air bags not deploying. The contact stated that the police were called and they issued a report. The contact had called his dealer who referred him to a body shop. The contact had the vehicle towed to a local body shop. The vehicle was not diagnosed by a dealer or independent mechanic. The vehicle damage was being repaired. The contact had researched online and related the failure to the federal safety agency Campaign Number: 24V115000 (Electrical System). The manufacturer was informed of the failure. The failure mileage was approximately 7,000.

Filed Jul 10, 2024 · Electrical · VA

There is an active recall for my vehicle Mercedez Benz GLC 300W4 for which I was NOT NOTIFIED BY THE DEALER AND MANUFACTURER. The recall states that certain 80A fuses installed might not meet production requirements. As a result, a contact interruption or an increased triggering resistance might occur. In this case, systems connected to the fuse might become inoperable. Among others, the vehicle might lose propulsion without warning, restraint functions or the instrument cluster might be impaired, increasing the risk of a crash and injuries. In addition, a risk of fire cannot be ruled out. An authorized Mercedes-Benz dealer will replace the respective main fuse box on the affected vehicles. The following is the SAFETY RISK associated with this recall. As a result, a contact interruption or an increased triggering resistance might occur. In this case, systems connected to the fuse might become inoperable. Among others, the vehicle might lose propulsion without warning, restraint functions or the instrument cluster might be impaired, increasing the risk of a crash and injuries. In addition, a risk of fire cannot be ruled out. I have noticed that check engine light turning on at times while driving which might be due to this fuse malfunctioning. Please take appropriate action and support my case. I can provide more details if required. Thank you.