Mercedes GLC Problems: 10 Common Issues

The Mercedes GLC is the successor of the GLK and competes in the compact luxury crossover segment, and is also seen as a mid-size SUV.

While boasting hybrid drivetrains and complete plug-in hybrid models and being packed with electronics and features, the Mercedes GLC Problems are seemingly high.

Common issues are tire scrubbing, the infotainment system displaying nothing, squeaky brakes, auxiliary battery malfunction, jerky and jolting transmission, wheel vibrations, software issues, rattle in the interior, 12V battery not charging, and head and taillights fogging up.

To help you make a more informed decision, we’ve broken down all of these common issues and looked at some Mercedes GLK recalls you need to be aware of (especially if you have one of these models).

10 Common Mercedes GLC Problems

1. Tire Scrubbing

Tire scrubbing happens when the car pushes through the front tires resulting in the front tires skipping over the ground and can cause loud thuds and vibration through the steering of the Mercedes GLC.

The Mercedes GLA also suffers from this problem; the cause can likely be the same as how the owners describe it.

Mercedes generally run a lot of caster on their models, and on sportier models, they combine this with less Ackerman angle to give the vehicle a sportier feel at high speed.

With the high caster and low Ackerman, the contact surface of the tire at full lock is minimal and causes the tires to scrub at low speeds and make that bad thudding and vibration.

The fix is to install non-run flat tires to minimize the wheel scrubbing effect, as run-flats side walls are very stiff and worsen the scrubbing effect.

To illustrate the problem, here is a video of a GLC maneuvering at low speed:

2. Infotainment System Displaying Nothing

Many owners had an issue where the infotainment display would turn completely black even though the radio and satnav would still play audio through the speakers.

Many owners of the GLC tried turning the car off and on again to no avail until one owner found the command screen power button that is situated close to the center console armrest of all places.

After a hard boot-up with the power button, some owners got their infotainment display up and working again.

In contrast, others had to take their vehicles to Mercedes to get a software update, and some needed an entirely new infotainment command screen.

3. Squeaky Brakes

From 2017 to 2021, the GLC was plagued with squeaky brakes, and it was all the fault of the brake pads used as standard.

When applying the brakes, lightly or heavily, it emits a very high-pitched squeak that irritates the driver and people close to the vehicle.

After 2018 the issue was only noticeable when the brakes were applied when reversing.

The fix is to use well-known brand-name brake pads from Brembo, Hawk, and EBC that have more stringent quality control over their products.

4. Auxiliary Battery Malfunction

The auxiliary battery malfunction is quite a common issue in the Mercedes model lineup that uses the 48V auxiliary battery.

Many owners of the GLC had to replace their 48V battery, which wouldn’t last long; some had to replace it again in under a year.

This was quickly fixed by an intelligent member of the GLC Forums, Toobad; he figured out the voltage converter of the 48V system was causing the “Auxiliary Battery Malfunction” warning, and it only cost $125 instead of a thousand for a new battery.

5. Jerky And Jolting Transmission

You would expect Mercedes to be on their A-game with automatic transmission at this point, as they have been in business since 1926 producing vehicles.

In the GLC, when the owners engage the sport and sport+ modes, the gearbox will jerk so hard when gearing down or up that, as one owner described:

“Not a small jerk but throw your head forward type of jerk and causes the steering wheel to shake.”

Quoted from GLC Forums user Kyliesmom11

Mercedes” told Quad22 on GLC Forums the transmission control unit needed to learn his driving style, and then the jerkiness would end, but after traveling 1,864 miles (3,000 kilometers), the transmission still did it.

6. Wheel Vibrations

Since the GLC is fitted with run-flat tires as standard and the sidewalls of a run-flat are extreme,ly hard, it causes harsh vibrations to be transferred to the steering wheel of”the car.

While driving over bumps and rough patches of the road, the owners of the GLC complained” about the vibration on the steering wheel.

The only fix is to replace the tires with standard non-run flat tires so the tire can dampen the impacts of a rough road or bumps.

7. Software Issues

The GLC is lined with modern features and tech, but with great tech comes a vast amount of electronic and software-related gremlins.

Most electronics are controlled through the command center display (infotainment screen). 

There have been numerous owners where the software resulted in the vehicle randomly unlocking doors, the parking brake engaging, and the windscreen washer fluid not spraying.

The fix to this issue was updating the electronics control unit’s firmware, which can take up to 9 hours to install through the Mercedes dealer network.

8. Rattle In The Interior

With a starting price of $43,850, you would expect the interior to be very well-finished and put together.

Unfortunately, the GLC has an annoying interior rattle in the rear of the vehicle; two things can cause the rattle.

The first culprit can be the luggage cover; when open, it will rattle on the housing of the cover. 

The only way to fix it is to install small rubber isolators between the hooking mechanism and the body of the entire housing.

9. 12V Battery Not Charging

The Mercedes GLC will display a warning saying the battery charge is critical and require charging.

Owners of the GLC thought it was because they needed to drive the vehicle longer for the battery to charge.

They experimented with it and found it would display the warning even after a long drive.

One owner replaced three batteries in 2 years, which is an atrocious lifespan for any automotive battery.

MBZ Master on Youtube has the best reasoning for why this is an issue with the GLC and most modern cars in this video:

10. Head And Taillights Fogging Up

While fogging up of the head and taillights won’t leave you stranded, it looks as if the car had some sort of incident in that water that ended up inside the housings.

Some owners received brand new vehicles with the lights fogged up due to condensation inside the lights.

One owner we mentioned earlier, Toobad from the GLC Forums, quoted out of the owner’s manual stipulating that under certain climatic conditions, it is normal for the headlights to get moisture on the inside, and it won’t affect the light’s function.

Mercedes GLC Recalls

While recalls fix vehicle issues, there is still a chance that some cars never got set.

Either the owner did everything DIY or took it to a private mechanic who never knew about the recalls.

So it is advantageous for you as a potential buyer or owner of a Mercedes GLC to learn about these recalls. 

And if you already own a GLC, take your vehicle to a dedicated Mercedes-Benz dealer or trustworthy mechanic as soon as possible to rectify these problems.

2016 Recalls

• 2016 GLC300 and 4Matic models may have a damaged ESP (Electronic Stability Program) control unit that was damaged before installation resulting in the stability program activating randomly and altering the vehicle’s path.
• 2016 GLC300 models, the steering column wiring harness is incorrectly routed, resulting in the harness chafing and randomly deploying the airbag.

2017 Recalls

• 2016 to 2017 GLC300, GLC300 4Matic, and GLC43 AMG models may have incorrectly adjusted headlights resulting in insufficient road illumination and thus failing to comply with the FMVSS (Federal Motor Vehicle Safety Standard) standards.
• 2017 GLC300 and 4Matic models, the starter will continuously try to start the engine in a scenario where the engine or transmission can’t turn over. It can begin to overheat, resulting in surrounding components melting and even catching fire.
• 2016 GLC300 models may have been updated with incorrect software on numerous control units of the vehicle resulting in the airbags not deploying as intended during a crash.
• 2016 to 2018 GLC300 and GLC300 4Matric models, the steering column wiring harness is incorrectly routed, resulting in the harness chafing and randomly deploying the airbag.
• 2017 GLC300, GLC300 4Matic, and GLC43 AMG models, the front seatbelt pre-tensioners may not function as intended resulting in the occupants not being adequately restrained during a crash.

2018 Recalls

• 2016 to 2018 GLC300 and 4Matic models, the steering column wiring harness is incorrectly routed, resulting in the harness chafing and randomly deploying the airbag.
•  2016 to 2018 GLC300, GLC300 4Matic, GLC43 AMG, 2018 GLC350e, and GLC63 AMG models, the rear outboard seatbelt latches can retract into the interior paneling resulting in occupants not being able to use the safety belts.
• 2017 to 2018 GLC300, GLC300 4Matic, and GLC43 AMG models equipped with the panoramic sunroof, the frontal and side plastic panels are not sufficiently bonded to the car and can detach and cause a road hazard.
• 2018 GLC300, GLC300 4Matic, GLC350e, and GLC43 AMG models equipped with LED headlights, the turn signals have the wrong color of pink or violet, thus failing to comply with the FMVSS standards.
• 2018 GLC300, GLC300 4Matic, GLC350e, and GLC43 AMG models, the driver-side airbag housing is made of defective steel, resulting when the airbag deploying it can rupture and shoot metal fragments into the interior.

2019 Recalls

• 2016 to 2017 model-year vehicles have a software problem causing the date and time given to the emergency services through the eCall (emergency call) to differ from the current date and time and potentially provide the wrong GPS location.
• 2018 to 2019 model-year vehicles equipped with Audio 20 head units and automatic child seat recognition, the status of the airbag may not be displayed correctly, resulting in it showing “ON” but won’t deploy during a crash.
• 2018 to 2019 GLC63 AMG and GLC63S models, the front airbags may have a delayed deployment on unbelted occupants during a crash, thus failing to comply with the FMVSS standards.
• 2019 GLC300 4Matic, GLC350e, GLC43 AMG, and GLC63 AMG models, the sensors detecting the front seat belts are inaccurate, resulting in the occupants wearing the safety belt but the vehicle not seeing it and disabling the pre-tensioners.
• 2019 model-year vehicles, the passenger side sun visor may have the incorrect airbag warning labels and is written in a foreign language resulting in failing the standards of the FMVSS.

2020 Recalls

• 2018 to 2020 GLC63 AMG models, the engine’s starter has an incorrectly installed power supply cable that can chafe against the starter housing and short-circuit, resulting in the vehicle stalling and increased fire risk.
• 2020 GLC300, GLC300 4Matic, and GLC63 AMG models, the eCall communication module may have a damaged electrical circuit resulting in relaying the wrong vehicle location.
• 2020 GLC300, GLC43 AMG, and GLC63 AMG models are equipped with rear seatbacks that can electrically unlatch; the latch is not strong enough to withstand specific loads when cargo hits the back of the seat.
• 2020 GLC350e models, the harness shield of the high voltage cables can not withstand the loads produced at specific conditions and can cause an electrical malfunction and stall the vehicle.
• 2020 model-year vehicles, the harness of the electric power steering may have been damaged during production resulting in loss of power steering.
• 2020 GLC63 AMG models the software version of the ESP may cause the system to react incorrectly, resulting in loss of vehicle control.

2021 Recalls

• 2016 to 2021 model-year vehicles, the software for the communication module can fail and send out the wrong vehicle location data when the eCall system is activated in a crash.
• 2016 to 2020 GLC300, 2017 to 2019 GLC43 AMG, and 2018 GLC63 AMG models equipped with a panoramic sunroof, the panel between the windscreen and the sunroof may not be bonded correctly to the vehicle resulting in it detaching and causing a road hazard.
• 2017 to 2020 GLC300, 2019 GLC350, and GLC43 AMG, the communication module of the eCall function may have been inadvertently deactivated during a service visit.
• 2019 to 2021 model-year vehicles, the multimedia display will remain black even after restart and reboot resulting in it not displaying an image when the rearview camera is activated, thus failing to comply with the FMVSS standards.
• 2021 model-year vehicles, the seat position switch has a faulty electrical contact resulting in the driver and passenger airbags and seat belt force limiters not functioning properly during a crash.
• 2020 to 2021 GLC300 and GLC63 AMG models, the connectors to the side crash sensors may come loose, thus delaying the deployment of the airbags and seatbelts in a crash.

2022 Recalls

• 2017 to 2022 model-year vehicles, the communication modules SIM card software may have an error causing it not to connect to mobile networks and disabling the eCall function.
• 2018 to 2021 model-year vehicles, the rearview camera won’t display an image due to a software error, thus failing to comply with the standards of the FMVSS.
• 2020 GLC350e models, the transmission harness is routed incorrectly and can chafe against the front drive shaft and cause loss of power.
• 2021 GLC300, GLC300 4Matic, GLC43 AMG, GLC63 AMG, and GLC63S AMG models, the connector to the headlights is not watertight and can result in headlight failure.

Final Thoughts On Mercedes GLC Problems

The number of faults is relatively high on the Mercedes GLC, but it is still better than the 21 problems of the Jeep Grand Cherokee.

The best thing to do if you own a Mercedes GLC is to take it to a Mercedes dealership and have them check for any recalls that haven’t been completed.

If you are in the market for a used Mercedes GLC, get a full vehicle history report and avoid any models with an outstanding recall.

Hopefully, you found this article helpful, and you can go to your next Mercedes GLC test drive knowing what to look out for.

FAQs