2021 Mercedes-Benz GLC: What to check before buying
Owners have filed 55 complaints with NHTSA about this car, most about the engine, electrical, and exterior lights. The 9 checks below target those problems, in the order you would do them at the car.
2021- Owner complaints
- 55
- Recalls
- 9
- Crashes reported
- 1
Your inspection sheet
Tick items off on your phone at the car, or print it. Ticks stay on this device.
0/9 checked
2021 Mercedes-Benz GLC: inspection sheet
Paperwork and questions
Before you go, or before you touch the car0/3
Walk-around and cabin
Engine off, key in hand0/2
Cold start, engine bay, and underside
Ask the seller not to warm the car up first0/3
Test drive
At least 20 minutes, with some highway0/1
These checks are specific to this model year. For tires, body panels, fluids, and the other basics every used car needs, use the general inspection guide.
Which GLC is it?
EPA figures for each version of the 2021 Mercedes-Benz GLC. Use them to confirm you are looking at the version that was advertised, and as a yardstick on the test drive.
| Version | Drive | EPA rating |
|---|---|---|
| 2.0L 4-cyl | 4WD, RWD | 24–25 mpg |
- Reset the trip computer at the start of the drive. A GLC that averages well under the EPA 24 mpg combined on a mixed route may have an engine or tire problem.
Check the odometer against these mileages
Owners report these failures starting around the mileages below. A car inside one of these ranges deserves a closer look at that part, or records showing it was already fixed.
Cylinder head failure, power loss
33,529–39,000 miles
Why these checks: what owners reported
NHTSA complaints for the 2021 Mercedes-Benz GLC, grouped by the part owners named. Open a row to read what goes wrong.
Engine211 crash
Sudden power loss is the main pattern. The engine misfires, shakes or idles rough, the check engine light comes on, and the car drops into limp mode, sometimes unable to exceed 40 mph. A restart often clears it for a while. Dealers repeatedly find a leaking or failed cylinder head, including a leaking exhaust valve, on the M264 engine. Failures appear around 33,529 to 39,000 miles, and some come back after a warranty repair. Out-of-warranty quotes run $7,600 to $10,000. One crash report involves a rear-end collision after the car lost power.
Electrical6No crashes
Water gets inside the headlight housing, usually on the passenger side, and the lamp flickers and then goes out. Several owners learn their VIN is excluded from recall 22V261000, which covers the same moisture problem on similar cars. Other reports describe repeated power loss with a check engine light and tows to the dealer in the first 6,620 miles, a low-battery app alert the dealer says to ignore, and a backover-prevention recall (21V354000) held up because the part is unavailable.
Exterior lights6No crashes
Headlights fog up or fill with water after rain, dim, and then stop working, sometimes on both sides. Failures are reported at 41,000 and about 92,700 miles. The repeated complaint is coverage. Dealers confirm the VIN is not part of recall 22V261000 and quote a paid repair, and one dealer blamed impact damage despite no visible cracks. One report also mentions high beams that will not auto dim, along with a fuel pump failure, misfires, and shutdown while driving.
Fuel system6No crashes
Fuel leaks are the most serious pattern. A high-pressure fuel line fails and gasoline pours from under the hood, in one case at about 1000 miles, and an incorrectly installed fuel line bracket leaves a large puddle of fuel and a car that will not start. Other reports describe power loss with a check engine light and a car stuck under 40 mph. One fuel pump failure is on a car the owner says is excluded from recall 23V880000.
Stalling at about 35 mph in the rain leads to a cylinder head replacement at 19,369 miles in one report, and the failure returns after the repair. That owner links it to recall 23V445000, but the VIN is not covered. The other complaint is a parts delay. The 23V445000 recall repair cannot be done because the part is unavailable, though no failure has occurred.
Body and structure3No crashes
Sunroof glass explodes outward with no prior impact, making a loud bang like a gunshot. In one case the closed fabric shade caught the fragments, which would otherwise have hit the occupants. Other complaints describe excessive frame rust that has needed repeated patches, and a front bumper on the coupe that leaves the radiator exposed to rock chips, which the dealer says it cannot address.
Transmission2No crashes
Repeated misfires, rough running, and hesitation come with a persistent check engine light, starting intermittently and getting worse until a dealer evaluation at about 65,000 miles. A separate pattern has the car suddenly refusing to go above 25 mph while driving 30 to 45 mph in city traffic, happening 3 times. The dealer says only a software update fixes it permanently, and that update is not yet available.
Acceleration and cruise control2No crashes
Distronic cruise control reads Georgia's minimum speed 40 signs as speed limits and cuts speed abruptly from about 70 mph to 40 mph, a real hazard in heavy traffic. Turning off the automatic speed adjustment stops it. A separate report describes hesitation when pressing the accelerator, with no warning light, at about 7,000 miles. The dealer did not diagnose or repair it.
In owners' own words
Excerpts from complaints GLC owners filed with NHTSA, as written. Listen for the same symptoms on your test drive.
Twice my car slowed down tremendously in traffic because of a bad cylinder head. I drive a 2021 Mercedes GLC 300 4matic with 33,529 miles. In reviewing other complaints, this is a common and known complaint. My check engine light came on and I could not go over 40 mph. This is very dangerous.
Filed with NHTSA, October 2025
While drive check engine light came on and car would go past 20 miles per hour. This is the second occurrence. First time this occurred October 2023 and covered under warranty. Head Gasket blew.
Filed with NHTSA, October 2024
I seen a recall for certain 2021 GLC 300 vehicles for moisture in right side headlamp, causing headlamp to blow (go out). This happened on my 2021 GLC 300. Same moisture issue, same year, same model, however, my vin number does not show that it has a recall. I believe this safety issue needs to be expanded to include my vehicle. Same issue, same year, same make and same model
Filed with NHTSA, April 2025
Mercedes App displays low battery alert. Brought to dealer who stated Mercedes told them (dealer) to inform anyone coming in with this issue to just disregard the alert in the app. Had the battery checked anyway. At the conclusion was told I had to “drive the car longer so the battery would recharge”.
Filed with NHTSA, December 2024
The headlights stopped working due to water entering the assembly unit. First one side went out and then eventually the other side went out. The car was brought in to the dealership to fix and they stated it wasn’t covered. I’m recently learning about a recall of this issue with my type of car and I’m being told that my vehicle is not included in the recall.
Filed with NHTSA, August 2025
Fuel line malfunctioned, car stopped , gasoline was pouring out from under the hood. I was "lucky" that it did not catch fire, fire department showed up, closed the street, car was towed, dealership " replaced high-pressure line of fuel system high pressure pump". It all started without a warning, suddenly after about 1 month of driving ( 1000 miles) a brand new Mercedes GLC300.
Filed with NHTSA, June 2021
Entered parked vehicle and noticed very strong gas fumes. Vehicle would not start. Looked under the vehicle and noticed very large quantity of gasoline on the ground. Vehicle was towed to Mercedes dealership in Rochester, Michigan. Diagnosis was an incorrectly installed fuel line bracket. New bracket was installed and problem was corrected.
Filed with NHTSA, June 2021
How the 2021 compares with other GLC years
Complaints for this year next to the average for the other model years, area by area.
The 2021 ranks fifth for owner complaints among 8 GLC years, close to the average of the others. Newer years have had less time to collect complaints, so compare like with like.
- Engine217
- Electrical610
- Exterior lights62
- Fuel system62
- Body and structure32
- Transmission25
Where the 2021 fits in the GLC's history
Redesigns and mid-cycle updates change what can go wrong.
The 2021 is the sixth model year of the GLC's first generation (2016–2022).
It includes the 2020 update.
What changed for 2020
- Updated MBUX Operating System
- New engines
- New steering wheel
- 12.3-inch digital cockpit
Recalls to confirm (9)
Recall repairs are free at any Mercedes-Benz dealer, but the seller may never have had them done. Check each campaign number against the VIN.
24V070000Exterior lightsFeb 2024
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2019-2022 GLC 300, 2020 GLC 350e, and 2020-2022 AMG GLC 43 vehicles. The headlights may be incorrectly adjusted too high and create a glare for oncoming traffic. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment.".
Risk: Incorrectly aimed headlights can reduce the visibility of oncoming traffic, increasing the risk of a crash.
Fix: Dealers will inspect the headlight adjustment and correct it if necessary, free of charge. Owner notification letters were mailed February 23, 2024. Owners may contact MBUSA customer service at 1-800-367-6372.
23V445000Fuel systemJun 2023
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021-2023 C-Class, E-Class, S-Class, CLS, SL, GT, GLC, GLE, GLS, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle details. The fuel pump may shutdown, which can result in a loss of drive power.
Risk: A loss of drive power can increase the risk of a crash.
Fix: Dealers will replace the fuel pump, free of charge. Owner notification letters were mailed on June 14, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2023070012.
22V365000ElectricalMay 2022
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.
Risk: A disabled eCall system would prevent a vehicle occupant from contacting the emergency services call center in an emergency, potentially delaying emergency responders and increasing the risk of injury.
Fix: The communication module software will be updated through an Over-the-Air (OTA) update or by a dealer, free of charge. Owner notification letters were mailed July 8, 2022. Owner notification letters will be mailed in phases, on July 8, 2022, May 17, 2024, July 29, 2024, and September 27, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's numbers are for this recall is 2022060005 and 2023110006.
22V261000Exterior lightsApr 2022
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 GLC 300, GLC 300 4Matic, AMG GLC 63 4Matic, AMG GLC 63 S 4Matic, and AMG GLC 43 4Matic vehicles. The electrical connection for the headlights may not be watertight, which can result in headlight failure.
Risk: Headlight failure can decrease visibility for both the driver and surrounding traffic, increasing the risk of a crash.
Fix: Dealers will inspect and replace the headlight sealing plugs, as necessary, free of charge. Owner notification letters were mailed June 3, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022050005.
21V527000AirbagsJul 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 CLS450, AMG E53, AMG CLS53, E350, E450, AMG GT43, AMG GT53, 2020 S450, S560, G550, AMG GLC63, 2020-2021 GLC300, and AMG G63 vehicles. The side crash sensor connectors may come loose, which could delay the activation of air bags and seatbelts during a side impact crash.
Risk: Air bags and seatbelts that don't function as intended can increase the risk of injury during a crash.
Fix: Dealers will inspect and replace as necessary, the side impact crash sensors, free of charge. Owner notification letters were mailed on September 3, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021070032/33.
21V354000Backup cameraMay 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2019-2021 CLA-Class, GLE/GLS-Class, A-Class, E-Class, E-Class Coupe and Convertible, GLA/GLB-Class, GLC-Class, CLS-Class, and AMG GT-Class 4-door Coupe vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The MBUX multimedia system software may cause the display to remain black, or reboot after startup. This could result in the rearview camera image not displaying properly. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility.".
Risk: A backup camera that displays a blank image reduces the driver's rear view, increasing the risk of a crash or injury.
Fix: The multimedia system software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters were mailed beginning June 28, 2021. Owners may contact MBUSA customer service at 1-800-367-6373. MBUSA's number for this recall is 2021050012.
21V230000SeatsApr 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C-Class, E-Class, E-Class Coupe and Convertible, GLC, CLS, AMG GT 4-door Coupe and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. A faulty electrical contact within the seat position switch may prevent the driver and passenger air bags and seat belt force limiters from properly activating during a crash.
Risk: Air bags and seat belts that do not perform properly in a crash can increase the risk of injury.
Fix: MBUSA will notify owners, and dealers will replace the seat position switches, free of charge. Owner letters were mailed May 21, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021040016.
21V072000CommunicationFeb 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2019 C300, E300, 2018-2020 CLA250, 2020 CLS450, AMG E53, AMG GT53, GLE450, 2018 AMG E63, AMG GTA, 2017-2020 GLA250, GLC300, 2019 GLC350, AMG GLC43, 2017-2018 GLE350, 2019 AMG GLC 43, GLC350, GLE400, 2017 GLS450, S550, C300 Cabrio, and 2018-2019 S560 vehicles. On June 18, 2021, an additional 9 vehicles were added, including certain 2021 GLA250, GLC300, 2018 S450, E400, and 2017 CLA250 vehicles. The communication module might have been inadvertently deactivated during a service visit, which could have disabled the Emergency Call (eCall) function.
Risk: A disabled eCall system would prevent a vehicle occupant from contacting emergency services through the call center in an emergency, potentially delaying emergency responders and increasing the risk of injury.
Fix: MBUSA will notify owners, and dealers will inspect the communication module and activate it, if necessary, free of charge. The recall began March 31, 2021. Letters for the owners of the 9 additional vehicles were mailed July 9, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021030005.
21V058000ElectricalFeb 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.
Risk: Failure of the eCall system may result in emergency responders being dispatched to the wrong location, increasing the risk of injury following a crash.
Fix: MBUSA will notify owners, and the communication module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. The recall began March 12, 2021. Owners may contact MBUSA customer service at 1-877-762-8267. MBUSA's number for this recall is 2021020025.
Also looking at these instead of a GLC?
Cars shoppers compare with the Mercedes-Benz GLC, with their own 2021 checklists.
2021 owner complaints, side by side
- 2021 Mercedes-Benz GLC55
- BMW X379
- Lexus RX209
- Tesla Model Y991
