Owners have filed 135 complaints
about the 2017 Mercedes Benz GLC300 with NHTSA between 2017 and 2026.
The largest single group is the engine & cooling.
Odometer readings owners gave when they filed. About half of all
complaints include one.
Under 1,000 miles
59.3%
1,000 – 9,999 miles
1731.5%
10,000 – 24,999 miles
35.6%
25,000 – 49,999 miles
713.0%
50,000 – 74,999 miles
814.8%
75,000 – 99,999 miles
1018.5%
100,000 – 149,999 miles
47.4%
When owners complained
A spike years after the car went on sale usually means a part wearing
out on schedule across the whole fleet — the kind of pattern no single
owner can see from inside their own car.
Mar 2017peak 12Feb 2026
NHTSA investigations into the 2017 Mercedes Benz GLC300
An investigation is the step before a recall: the agency has seen enough
complaints to look into a pattern itself. An open one means it thinks
something may be wrong and nothing has been fixed yet.
From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.C...
PE21001Opened 8 Jan 2021Closed 14 Oct 2021STRUCTURE:BODY:ROOF AND PILLARS
Front Roof Panel Detachment
On January 8, 2021, after ongoing review with Mercedes Benz, the National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation (ODI) opened PE21-001 to assess allegations of front roof panel detachments while driving at highway speeds in certain 2015 Mercedes-Benz (Mercedes) C-Class vehicles.The subject front roof panel is a stationary panel composed of polycarbonate and is attached to the vehicle via adhesive at the time of manufacture. The panel is found on subject vehicles equipped with panoramic sunroofs. Over time, the subject panels may exhibit cosmetic degradati...
Complaints that involved harm
Reports where the owner recorded a crash, a fire, an injury or a death.
at 25,000 milesHuntsville, ALCrash1 injured
AIR BAGS
TL* THE CONTACT OWNS A 2017 MERCEDES BENZ GLC300. THE CONTACT STATED THAT WHILE HIS WIFE WAS DRIVING APPROXIMATELY 40 MPH, THE VEHICLE CRASHED INTO A 2ND VEHICLE. DURING THE CRASH THE FRONT END WAS SEVERELY DAMAGED BUT THE AIR BAGS DID NOT DEPLOY. ALSO, THE COLLISION AVOIDANCE SYSTEM MALFUNCTIONED AND DID NOT STOP THE VEHICLE TO AVOID THE COLLISION. THE DRIVER SUSTAINED BRUISES TO THE TORSO AREA WHICH REQUIRED MEDICAL TREATMENT. AN OCCUPANT FROM THE 2ND VEHICLE WAS TRANSPORTED TO THE HOSPITAL BY AMBULANCE. NO FURTHER INFORMATION WAS AVAILABLE. A POLICE REPORT WAS TAKEN AT THE SCENE AND THE VEHICLE WAS TOWED AWAY. THE LOCAL DEALER MERCEDES BENZ OF HUNTSVILLE (6220 UNIVERSITY DR. HUNTSVILLE, AL) AND THE MANUFACTURER WERE NOTIFIED OF THE INCIDENT. THE CAUSE OF THE FAILURES WERE NOT DETERMINED. THE FAILURE MILEAGE WAS 25,000.
NHTSA complaint #11338128 — an unverified report by a vehicle owner.
TL* THE CONTACT OWNS A 2017 MERCEDES BENZ GLC300. THE CONTACT STATED THAT WHILE HIS WIFE WAS DRIVING APPROXIMATELY 40 MPH, THE VEHICLE CRASHED INTO A 2ND VEHICLE. DURING THE CRASH THE FRONT END WAS SEVERELY DAMAGED BUT THE AIR BAGS DID NOT DEPLOY. ALSO, THE COLLISION AVOIDANCE SYSTEM MALFUNCTIONED AND DID NOT STOP THE VEHICLE TO AVOID THE COLLISION. THE DRIVER SUSTAINED BRUISES TO THE TORSO AREA WHICH REQUIRED MEDICAL TREATMENT. AN OCCUPANT FROM THE 2ND VEHICLE WAS TRANSPORTED TO THE HOSPITAL BY AMBULANCE. NO FURTHER INFORMATION WAS AVAILABLE. A POLICE REPORT WAS TAKEN AT THE SCENE AND THE VEHICLE WAS TOWED AWAY. THE LOCAL DEALER MERCEDES BENZ OF HUNTSVILLE (6220 UNIVERSITY DR. HUNTSVILLE, AL) AND THE MANUFACTURER WERE NOTIFIED OF THE INCIDENT. THE CAUSE OF THE FAILURES WERE NOT DETERMINED. THE FAILURE MILEAGE WAS 25,000.
NHTSA complaint #11338128 — an unverified report by a vehicle owner.
NHTSA complaint #11112071 — an unverified report by a vehicle owner.
at 9,000 milesCypress, CAFire
ENGINE
TL* THE CONTACT OWNS A 2017 MERCEDES-BENZ GLC300. WHILE PARKED IN THE DRIVEWAY, THE VEHICLE CAUGHT FIRE. THE FAILURE WAS DUE TO A MANUFACTURER DEFECT. THERE WERE NO INJURIES. THE FIRE DEPARTMENT WAS CONTACTED. A POLICE REPORT WAS FILED. THE VEHICLE WAS NOT TOWED. AN UNKNOWN DEALER LOCATION WAS CONTACTED, BUT THE VEHICLE WAS NOT TAKEN TO THE DEALER. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 9,000.
NHTSA complaint #11076876 — an unverified report by a vehicle owner.
The most recent complaints
In the owners' own words, exactly as filed with NHTSA.
Lancaster, TX
FUEL/PROPULSION SYSTEM
I smell gas in my car. There is a recall for the fuel parts on the 2019. I have a 2017 with the same issue.
NHTSA complaint #11715888 — an unverified report by a vehicle owner.
at 130,000 milesStevenson Ranch, CA
AIR BAGS
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the messages "Driver’s Air Bag Malfunction - Service Required" and "Collision Prevention Assist Unavailable" were displayed. The vehicle was taken to an independent mechanic who diagnosed and determined that the air bag had malfunctioned. The vehicle was not repaired. The contact called the dealer, but the vehicle was not inspected or repaired. The manufacturer was made aware of the failure and referred the contact to the NHSTA Hotline for assistance. The failure mileage was approximately 130,000.
NHTSA complaint #11715404 — an unverified report by a vehicle owner.
at 71,000 milesAustin, TX
SEAT BELTS: REAR/OTHER:BUCKLE ASSEMBLY
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while parked and attempting to release the seat belt, the seat belt remained latched. The contact stated that after the third attempt, the seat belt operated as needed. The failure had occurred in the front driver’s and passenger’s side seat belts. The vehicle was taken to a dealer, where it was determined that the buckle and needed to be replaced. The seat belt buckle was replaced, and the vehicle was repaired. The manufacturer was notified of the failure but offered no assistance because the warranty had expired. The approximate failure mileage was 71,000.
NHTSA complaint #11715340 — an unverified report by a vehicle owner.
at 130,000 milesStevenson Ranch, CA
FORWARD COLLISION AVOIDANCE
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the messages "Driver’s Air Bag Malfunction - Service Required" and "Collision Prevention Assist Unavailable" were displayed. The vehicle was taken to an independent mechanic who diagnosed and determined that the air bag had malfunctioned. The vehicle was not repaired. The contact called the dealer, but the vehicle was not inspected or repaired. The manufacturer was made aware of the failure and referred the contact to the NHSTA Hotline for assistance. The failure mileage was approximately 130,000.
NHTSA complaint #11715404 — an unverified report by a vehicle owner.
at 70,000 milesStuart, FL
VISIBILITY:SUN/MOON ROOF ASSEMBLY
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while driving approximately 30 MPH, the first panel of the panoramic sunroof went off track and failed to close as intended. The contact stated that while inspecting the vehicle, the panoramic sunroof glass was pushed down firmly, and the sunroof closed. The contact attempted to open the sunroof, but the sunroof failed to operate as intended; however, the contact heard a motorized sound coming from the sunroof. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 70,000.
NHTSA complaint #11698964 — an unverified report by a vehicle owner.
Raleigh, NC
POWER TRAIN
The Valve body control failed. I took the car into the dealership but upon doing some searching this seems to be a common issue amongst owners of this vehicle/make model. The transmission won't go beyond 5th gear (of 9) so it's is dangerous to drive on the interstate. The car doesn't shift into drive, only shifts into N, the reverts automatically to park. It required the engine shutting on/off multiple times and only then does it go into 3rd gear, causing the vehicle to jump due to missing gears. This issue could leave an owner stranded at any time and cause injury due to the limitations of the gears. It was inspected and confirmed behavior by Mercedes in Durham NC. There were no warning lamps, there were no signs of the issue. The technician did plug it in and was able to read the fault codes but it didn't trigger a light. The appeared first about 45 days ago, and the vehicle was taken in to be looked at 7/21/25.
NHTSA complaint #11680130 — an unverified report by a vehicle owner.
Virginia Beach, VA
UNKNOWN OR OTHER
My vehicle goes into neutral while driving which poses a major risk.
NHTSA complaint #11669974 — an unverified report by a vehicle owner.
Virginia Beach, VA
ELECTRICAL SYSTEM
My vehicle goes into neutral while driving which poses a major risk.
NHTSA complaint #11669974 — an unverified report by a vehicle owner.
at 82,000 milesEvans, GA
VISIBILITY:SUN/MOON ROOF ASSEMBLY
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that on several occasions while opening the sunroof, the contact heard an abnormal grinding sound. Additionally, the contact stated that the sunroof failed to close as intended. The vehicle was taken to a dealer where it was diagnosed and determined that the sunroof rails needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 82,000.
NHTSA complaint #11667611 — an unverified report by a vehicle owner.
Richmond, VA
POWER TRAIN
Vehicle has previous recalls done and still has the same issues with recall. Srs code no air bag will deploy. Dealer ship refused to service vehicle due to miscommunication and I'm driving a defective vehicle without an airbag which could lead to a bad accident waiting to happened. I will like to file a complaint against Mercedes of Richmond for refusing to service my vehicle without a defective air bag and the passenger seat bear latch doesn't retract properly. So I'm currently dealing with 2 huge safety hazard and was denied service due to a miscommunication with Steven Powers (service technician) at Mercedes of Richmond! I will like an investigation done.
NHTSA complaint #11666296 — an unverified report by a vehicle owner.
Richmond, VA
SEAT BELTS
Vehicle has previous recalls done and still has the same issues with recall. Srs code no air bag will deploy. Dealer ship refused to service vehicle due to miscommunication and I'm driving a defective vehicle without an airbag which could lead to a bad accident waiting to happened. I will like to file a complaint against Mercedes of Richmond for refusing to service my vehicle without a defective air bag and the passenger seat bear latch doesn't retract properly. So I'm currently dealing with 2 huge safety hazard and was denied service due to a miscommunication with Steven Powers (service technician) at Mercedes of Richmond! I will like an investigation done.
NHTSA complaint #11666296 — an unverified report by a vehicle owner.
Richmond, VA
AIR BAGS
Vehicle has previous recalls done and still has the same issues with recall. Srs code no air bag will deploy. Dealer ship refused to service vehicle due to miscommunication and I'm driving a defective vehicle without an airbag which could lead to a bad accident waiting to happened. I will like to file a complaint against Mercedes of Richmond for refusing to service my vehicle without a defective air bag and the passenger seat bear latch doesn't retract properly. So I'm currently dealing with 2 huge safety hazard and was denied service due to a miscommunication with Steven Powers (service technician) at Mercedes of Richmond! I will like an investigation done.
NHTSA complaint #11666296 — an unverified report by a vehicle owner.
Richmond, VA
POWER TRAIN
No incident my vehicle has a front left malfunction service required light and issues with the passenger seatbelt not proper latching. Upon checking I notice my car had previous recalls done. It seems as if the same issues has come about. NHTSA: 18v177- seat belt not retracting properly. NHTSA: 17V627 is related to the steering column switch replacement of clock spring. So if me or a family member was to get into an accident no airbag will deploy! Huge safety hazard!
NHTSA complaint #11664823 — an unverified report by a vehicle owner.
Richmond, VA
SEAT BELTS
No incident my vehicle has a front left malfunction service required light and issues with the passenger seatbelt not proper latching. Upon checking I notice my car had previous recalls done. It seems as if the same issues has come about. NHTSA: 18v177- seat belt not retracting properly. NHTSA: 17V627 is related to the steering column switch replacement of clock spring. So if me or a family member was to get into an accident no airbag will deploy! Huge safety hazard!
NHTSA complaint #11664823 — an unverified report by a vehicle owner.
Richmond, VA
AIR BAGS
No incident my vehicle has a front left malfunction service required light and issues with the passenger seatbelt not proper latching. Upon checking I notice my car had previous recalls done. It seems as if the same issues has come about. NHTSA: 18v177- seat belt not retracting properly. NHTSA: 17V627 is related to the steering column switch replacement of clock spring. So if me or a family member was to get into an accident no airbag will deploy! Huge safety hazard!
NHTSA complaint #11664823 — an unverified report by a vehicle owner.
Bloomfield, NJ
VISIBILITY:REARVIEW MIRRORS/DEVICES:EXTERIOR
The driver mirror and passenger mirror are warping or having some type of melting effect happening to it.
NHTSA complaint #11664500 — an unverified report by a vehicle owner.
at 120,000 milesPetersburg, VA
SEAT BELTS
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while driving on several occasions at various speeds, the front passenger’s side seat belt retractor failed to extend or retract as intended and became stuck. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. Additionally, the contact stated that on several occasions while started and running, the message “Service Soon” was displayed. The vehicle was taken to a dealer where it was diagnosed and determined that the clock spring needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 120,000.
NHTSA complaint #11664416 — an unverified report by a vehicle owner.
at 120,000 milesPetersburg, VA
AIR BAGS:FRONTAL:DRIVER CLOCKSPRING/SPIRAL CASSETTE
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while driving on several occasions at various speeds, the front passenger’s side seat belt retractor failed to extend or retract as intended and became stuck. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. Additionally, the contact stated that on several occasions while started and running, the message “Service Soon” was displayed. The vehicle was taken to a dealer where it was diagnosed and determined that the clock spring needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 120,000.
NHTSA complaint #11664416 — an unverified report by a vehicle owner.
Meriden, CT
ENGINE
-The malfunctioned component is the Positive Crankcase Ventilation. - Vehicle wanted to stall and did not want to accelerate while in the middle lane on the highway with my family. - Yes it has been diagnosis by certified mechanic - The check engine light turned on at the time of the incident and has been turning on and off ever since.
NHTSA complaint #11654950 — an unverified report by a vehicle owner.
Sutter, CA
ENGINE
I was driving and my engine light came on. I ran the code and it came up as P052E which has to do with the positive crankcase ventilation regulator valve. I’ve heard that this part goes out very often on the Mercedes Benz.
NHTSA complaint #11651403 — an unverified report by a vehicle owner.
Waterbury, CT
ENGINE
Car stalled in traffic due to code P052E PCV regulator valve
NHTSA complaint #11649075 — an unverified report by a vehicle owner.
at 55,000 milesHillside, NJ
FUEL SYSTEM, GASOLINE:STORAGE:TANK ASSEMBLY
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated that while operating the vehicle, the fuel gauge provided incorrect information and indicated that there was no fuel in the fuel tank. The contact stated that the failure was intermittent and sometimes occurred immediately after refueling. The vehicle was taken to the local dealer who diagnosed the vehicle and determined that the fuel tank needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 55,000. The VIN was not available.
NHTSA complaint #11637735 — an unverified report by a vehicle owner.
El Paso, TX
FUEL/PROPULSION SYSTEM
Strong gasoline smell coming from the engine bay every morning at start up. I removed protective plastic lining from the under carriage to identify the issue. I identified a lot of gasoline dripping from the top portion of the engine compartment where the High Pressure Fuel Pump is located. There was no warning or check engine lights that alerted of this issue of a gasoline leak. This is very dangerous as it could cause the vehicle to catch fire.
NHTSA complaint #11631359 — an unverified report by a vehicle owner.
at 88,100 milesManhattan, NY
VISIBILITY:SUN/MOON ROOF ASSEMBLY
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken back to the dealer and the contact was informed that the vehicle was repaired. The contact stated that the dealer had only reset the codes. In addition, the contact stated that the tire pressure sensor warning light was illuminated. The contact stated that the sunroof latch failed to close as needed using the sunroof power switch. 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 88,100.
NHTSA complaint #11626697 — an unverified report by a vehicle owner.
at 88,100 milesManhattan, NY
TIRES:PRESSURE MONITORING AND REGULATING SYSTEMS
The contact owns a 2017 Mercedes-Benz GLC300. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken back to the dealer and the contact was informed that the vehicle was repaired. The contact stated that the dealer had only reset the codes. In addition, the contact stated that the tire pressure sensor warning light was illuminated. The contact stated that the sunroof latch failed to close as needed using the sunroof power switch. 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 88,100.
NHTSA complaint #11626697 — an unverified report by a vehicle owner.