Owners have filed 128 complaints
about the 2018 Mercedes Benz C 300 with NHTSA between 2018 and 2026.
The largest single group is the engine & cooling.
Across this model's run it ranks 2 of 8 worst.
The letter says how bad. This says what kind — whether this year drew
an unusual number of complaints, unusually dangerous
ones, or failures that arrived unusually early.
The dashed ring is 50 — the national norm. Further out is worse.
Complaint volume — 77
Against the median year of the Mercedes Benz C 300. 50 means typical for this
model; 100 means roughly double.
Severity — 44
8.6% of these complaints
involved a crash, fire, injury or death, against a national rate of
9.7%.
Early failure — 71
41% of failures with a mileage on record happened under
36,000 miles, against a national rate of
29%.
How 2018 compares with every other Mercedes Benz C 300
Odometer readings owners gave when they filed. About half of all
complaints include one.
Under 1,000 miles
413.8%
1,000 – 9,999 miles
310.3%
10,000 – 24,999 miles
413.8%
25,000 – 49,999 miles
310.3%
50,000 – 74,999 miles
1034.5%
75,000 – 99,999 miles
413.8%
100,000 – 149,999 miles
13.4%
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.
Jun 2018peak 7Jun 2026
NHTSA investigations into the 2018 Mercedes Benz C 300
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...
Complaints that involved harm
Reports where the owner recorded a crash, a fire, an injury or a death.
Clovis, CACrash
STRUCTURE:BODY
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
Clovis, CACrash
ELECTRICAL SYSTEM
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
Clovis, CACrash
STRUCTURE:BODY
While I was driving to work in a heavy rain my abs malfunction light came on in my car. I decided to take it to the Mercedes-Benz dealership in Fresno. They said it was the ABS module that needed to be replaced. After being in the shop for almost 3 weeks they said it was fixed. When I went to pick it up, the moment I turned it on the ABS malfunction light came on again. I was told that it was okay to drive and they would have somebody come check it out at my work the next day. My car went back into the shop for another week and they could not figure out what was wrong with it. They did take pictures and the second time I took it in they noticed a bunch of water underneath the floorboard. By this time, I had lost confidence in them fixing my car the manager basically kicked me off the lot and told me never to go back again. So I continued to drive my car since I was told it was okay first time they fixed it. Short while later, I rear-ended another car. The ABS system did not warn me that I was too close. When I took my car in to get the body work fixed I was also given a name of somebody who would be able to fix the electrical problems and insurance would pay for it. He was able to fix the ABS system but could not find where the short was that controlled the passenger seat and the driver side back seat window and for the needle that tells me if my car is overheating. Nobody could figure out where the water had been coming from. It wasn't until recently when we just had a heavy storm that I noticed water leaking from inside the car through a seam. The running boards on the top of my car were not installed correctly so water seeps in there during rains and then it travels down underneath my floorboards and sits which was the cause of the shorts in my electrical system. My concern is that I don't know how bad other components of the car might be that one of the wires might at any of the wires might short while I'm driving now but unable to download receipts which I have
NHTSA complaint #11589822 — an unverified report by a vehicle owner.
Clovis, CACrash
FORWARD COLLISION AVOIDANCE: WARNINGS
While I was driving to work in a heavy rain my abs malfunction light came on in my car. I decided to take it to the Mercedes-Benz dealership in Fresno. They said it was the ABS module that needed to be replaced. After being in the shop for almost 3 weeks they said it was fixed. When I went to pick it up, the moment I turned it on the ABS malfunction light came on again. I was told that it was okay to drive and they would have somebody come check it out at my work the next day. My car went back into the shop for another week and they could not figure out what was wrong with it. They did take pictures and the second time I took it in they noticed a bunch of water underneath the floorboard. By this time, I had lost confidence in them fixing my car the manager basically kicked me off the lot and told me never to go back again. So I continued to drive my car since I was told it was okay first time they fixed it. Short while later, I rear-ended another car. The ABS system did not warn me that I was too close. When I took my car in to get the body work fixed I was also given a name of somebody who would be able to fix the electrical problems and insurance would pay for it. He was able to fix the ABS system but could not find where the short was that controlled the passenger seat and the driver side back seat window and for the needle that tells me if my car is overheating. Nobody could figure out where the water had been coming from. It wasn't until recently when we just had a heavy storm that I noticed water leaking from inside the car through a seam. The running boards on the top of my car were not installed correctly so water seeps in there during rains and then it travels down underneath my floorboards and sits which was the cause of the shorts in my electrical system. My concern is that I don't know how bad other components of the car might be that one of the wires might at any of the wires might short while I'm driving now but unable to download receipts which I have
NHTSA complaint #11589822 — an unverified report by a vehicle owner.
While I was driving to work in a heavy rain my abs malfunction light came on in my car. I decided to take it to the Mercedes-Benz dealership in Fresno. They said it was the ABS module that needed to be replaced. After being in the shop for almost 3 weeks they said it was fixed. When I went to pick it up, the moment I turned it on the ABS malfunction light came on again. I was told that it was okay to drive and they would have somebody come check it out at my work the next day. My car went back into the shop for another week and they could not figure out what was wrong with it. They did take pictures and the second time I took it in they noticed a bunch of water underneath the floorboard. By this time, I had lost confidence in them fixing my car the manager basically kicked me off the lot and told me never to go back again. So I continued to drive my car since I was told it was okay first time they fixed it. Short while later, I rear-ended another car. The ABS system did not warn me that I was too close. When I took my car in to get the body work fixed I was also given a name of somebody who would be able to fix the electrical problems and insurance would pay for it. He was able to fix the ABS system but could not find where the short was that controlled the passenger seat and the driver side back seat window and for the needle that tells me if my car is overheating. Nobody could figure out where the water had been coming from. It wasn't until recently when we just had a heavy storm that I noticed water leaking from inside the car through a seam. The running boards on the top of my car were not installed correctly so water seeps in there during rains and then it travels down underneath my floorboards and sits which was the cause of the shorts in my electrical system. My concern is that I don't know how bad other components of the car might be that one of the wires might at any of the wires might short while I'm driving now but unable to download receipts which I have
NHTSA complaint #11589822 — an unverified report by a vehicle owner.
The most recent complaints
In the owners' own words, exactly as filed with NHTSA.
Lakewood, CA
UNKNOWN OR OTHER
Transmission failed, yes available for inspection Very bad safety issue Yes it has been confirmed by dealship Yes by the deanship Yes there was warning lamps that appeared in January 2026
NHTSA complaint #11744612 — an unverified report by a vehicle owner.
Sacramento, CA
STRUCTURE
The contact's wife owns a 2018 Mercedes-Benz C300. The contact stated that while washing the vehicle, a part of the panoramic roof started moving while depressing the glass. The contact stated that there was water leaking into the vehicle from the glass. Upon investigation, the contact discovered NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included in the recall. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was filed. The manufacturer confirmed that the VIN was not included in the recall. The contact was then referred to the NHTSA Hotline to report the failure. The failure mileage was unknown.
NHTSA complaint #11722229 — an unverified report by a vehicle owner.
Glendale, CA
ENGINE
Check engine light comes on, Error Code P052E, after a lot of research, this is a known defective part by Benz. Huge safety issue not addressed by them. Very costly to fix for a customer. There is a new and improved replacement part from Benz indicating they are aware of the faulty old parts that are currently in those cars but yet they have failed to do a recall.
NHTSA complaint #11709871 — an unverified report by a vehicle owner.
Tempe, AZ
ENGINE
My vehicle only had 31,000 miles and I experienced engine failure. I bought a new engine for 16, 500. 00 dollars. Mercedes Benz did nothing. I almost got in to several accidents because the engine completely stop on the interstate. Almost got hit by several cars. This is unacceptable.
NHTSA complaint #11695170 — an unverified report by a vehicle owner.
Miami, FL
UNKNOWN OR OTHER
Rearview Camera is not displayed when the vehicle is placed in reverse. The display shows a black screen. A Recall Notice has been published for other vehicles of the same year, make, and model. The failure of the Rearview Camera results in safety risks during normal use of the vehicle.
NHTSA complaint #11692113 — an unverified report by a vehicle owner.
Chantilly, VA
SEAT BELTS
I have noticed the driver seat belt not retracting after usage. Upon looking online I saw a post about a recall. Called local Benz dealership and BenzUSA customer service both said my Vin is not part of the specified recall.
NHTSA complaint #11689895 — an unverified report by a vehicle owner.
at 109,000 milesCypress, TX
STRUCTURE
The contact owns a 2018 Mercedes-Benz C300. The contact stated that while driving approximately 60 MPH, a part of the panoramic roof towards the driver's side detached from the vehicle. The contact pulled over to inspect the vehicle. The part was no longer attached, and the contact had to continue driving. The failure caused additional electrical failures due to water entering the cabin of the vehicle. The contact stated that the sunroof failed to open, and the infotainment center was inoperable. The contact found information on NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included. The vehicle was taken to the dealer, who related the failure to the recall; however, the vehicle could not be repaired under the recall because the VIN was not available. The vehicle was not repaired. The manufacturer was informed of the failure and opened a case. The manufacturer confirmed that the VIN was not included in the recall. The manufacturer referred the contact to the NHTSA Hotline to file a complaint. The failure mileage was approximately 109,000.
NHTSA complaint #11681537 — an unverified report by a vehicle owner.
at 49,000 milesPorter Ranch, CA
STRUCTURE
The contact owns a 2018 Mercedes-Benz C300. The contact stated that after washing the vehicle, the contact became aware that the adhesive attaching the rear window to the convertible top had started to detach. Upon further inspection, the contact became aware that water had seeped into the vehicle through the crack. There was no warning light illuminated. The local dealer was contacted; however, the vehicle was not diagnosed. The contact was also informed that the VIN was not under recall. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 49,000.
NHTSA complaint #11664906 — an unverified report by a vehicle owner.
Pasadena, TX
TIRES
In August 2024, a Mercedes-Benz dealership in Salisbury, MD installed the wrong type of rear tires on my vehicle. I was not informed they were mismatched or inappropriate for my vehicle. I later drove across the country with my infant child in the backseat, believing the tires were new and safe. On April 17, 2025, a certified tire shop in Texas (Discount Tire) inspected the tires and told me they were not suitable for my car and were already too old to be considered new — despite having been installed just 8 months earlier. They refused to buy them back or reinstall them due to the age and mismatch. Additionally, the dealership had earlier failed to correctly diagnose my ABS system, citing water damage but doing no further inspection. They also missed a major coolant leak and water pump failure, despite charging me for multiple diagnostics. Their negligence in both diagnosis and tire installation directly put me and my child at serious safety risk, especially while traveling long distance at highway speeds.
NHTSA complaint #11663518 — an unverified report by a vehicle owner.
Hixson, TN
BACK OVER PREVENTION: SENSING SYSTEM: CAMERA
I recently purchased a 2018 Mercedes C300 and I noticed the rear view camera will not show an image. It mechanically will open and all other cameras are fully functional but the image will not show instead I see a icon of a camera in a red crossed circle. When doing VIN serch on my vehicle I don't see any open recalls. However, I noticed that NHTSA campaign number 22V232000 has recalled this exact issue. Although the report 573 says for it applying to 2019 models but with a production date between 2017 to 2021 vehicles applying. So I believe this recall should also apply to my vehicle.
NHTSA complaint #11647340 — an unverified report by a vehicle owner.
at 52,300 milesPueblo West, CO
FUEL SYSTEM, GASOLINE
The contact owns a 2018 Mercedes-Benz C300. The contact stated that while the vehicle was parked inside the garage, there was a strong fuel odor inside the garage. The contact stated that there was fuel leaking from the vehicle. There were no warning lights illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 52,300.
NHTSA complaint #11642176 — an unverified report by a vehicle owner.
Flushing, NY
ENGINE
The engine light is on with only 35000 miles. Upon using an OBD2 scanner, error code P052e positive crankcase ventilation(PCV) malfunction was detected. It's a problem that I researched and noticed a lot of people having the same issue. I was told that this can cause the car to stall or shut down? This causes serious risk and safety issues to drivers, passengers, and pedestrians. With so many complains about this problem, I believe the manufacturer and dealers should take responsibility before tragedies happen.
NHTSA complaint #11640265 — an unverified report by a vehicle owner.
Flushing, NY
FUEL/PROPULSION SYSTEM
The engine light is on with only 35000 miles. Upon using an OBD2 scanner, error code P052e positive crankcase ventilation(PCV) malfunction was detected. It's a problem that I researched and noticed a lot of people having the same issue. I was told that this can cause the car to stall or shut down? This causes serious risk and safety issues to drivers, passengers, and pedestrians. With so many complains about this problem, I believe the manufacturer and dealers should take responsibility before tragedies happen.
NHTSA complaint #11640265 — an unverified report by a vehicle owner.
at 50,000 milesLaguna Niguel, CA
VISIBILITY
The contact owns a 2018 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the rear window glass which was not properly bonded had become loosened. The vehicle was not diagnosed or repaired. The VIN was not included in NHTSA Campaign Number: 18V608000 (VISIBILITY). The manufacturer was not notified of the failure. The failure mileage was 50,000.
NHTSA complaint #11617349 — an unverified report by a vehicle owner.
Durham, NC
STRUCTURE:BODY
Problem a recall was done on certain Mercedes vehicles where the front panel of the roof between the panoramic sunroof and windshield has defects in gluing or bonding agent from the manufacture. I believe my vehicle is showing possible premature bonding agent issues below the surface of panel. Where the manufacture bonding glue is causing interior flaking and cracking and lifting from the stress of the wrong/incorrect specified bonding material not used during the manufacturing process . I am afraid that while driving my vehicle at highway speed has the opportunity / potential for my panel to eventually break off and cause damage of flying panel pieces to harm myself or other vehicles traveling on the road. I believe the wrong bonding material is also causing other issues with the panel and the workmanship material used. My vehicle falls under the year, make, W222 and I am already seeing issues with my panel that by being proactive on my vehicle then reactive. I don’t want to wait for my panel to fly off when early detection and rectification is the safest way/option. My second concern is that there has already been changing dates on this recall information sent out in 2017, 2019 and now 2021. I am worried!!
NHTSA complaint #11614170 — an unverified report by a vehicle owner.
at 57,000 milesPittsburg, CA
STEERING:RACK AND PINION
The contact owns a 2018 Mercedes-Benz C300. While driving at various speeds, the contact could hear an abnormal sound from the transmission. The vehicle was taken to a local independent mechanic where it was diagnosed that the rack and pinion needed to be replaced. The vehicle was not repaired. The vehicle was then taken to a local dealer for diagnosis, but the failure could not be replicated. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 57,000.
NHTSA complaint #11610269 — an unverified report by a vehicle owner.
Concord, NC
ENGINE
I need the Crankcase ventilation valve replaced and have heard many complaints about this repair.
NHTSA complaint #11606218 — an unverified report by a vehicle owner.
Carteret, NJ
UNKNOWN OR OTHER
The day after I purchased my c300, the engine light popped on. I went back to dealer and they said it was a recall because of a crank case (PCV). I was upset because they never said anything about it. This was April of 2024. Note:(This Dealer was not Ray Catina’s of Edison). I went to Ray Catina’s in Edison for them to inspect car and I have been calling because I was told it was a national recall and it was on back order and should be here in June. It is now almost August and I called on the 23rd of July and received a call from Ray Catena on the 24th for them to tell me that “they were told that the new plan from Mercedes is to bring my car in and they will clear code. That’s what they are told to do.” To me, this is NOT fixing the issue. I am a little aggravated because I bought my car on [XXX] and have NOT been able to feel good because not sure what ramifications will come with me driving my car with this issue. I was told that driving with this engine light on and code that it will not harm my car. They now say Mercedes was told to reset the code and that will resolve issue? I believe this is a band aid not a fix!!! I’m a little upset. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11604857 — an unverified report by a vehicle owner.
Carteret, NJ
ENGINE
The day after I purchased my c300, the engine light popped on. I went back to dealer and they said it was a recall because of a crank case (PCV). I was upset because they never said anything about it. This was April of 2024. Note:(This Dealer was not Ray Catina’s of Edison). I went to Ray Catina’s in Edison for them to inspect car and I have been calling because I was told it was a national recall and it was on back order and should be here in June. It is now almost August and I called on the 23rd of July and received a call from Ray Catena on the 24th for them to tell me that “they were told that the new plan from Mercedes is to bring my car in and they will clear code. That’s what they are told to do.” To me, this is NOT fixing the issue. I am a little aggravated because I bought my car on [XXX] and have NOT been able to feel good because not sure what ramifications will come with me driving my car with this issue. I was told that driving with this engine light on and code that it will not harm my car. They now say Mercedes was told to reset the code and that will resolve issue? I believe this is a band aid not a fix!!! I’m a little upset. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11604857 — an unverified report by a vehicle owner.
Philadelphia, PA
UNKNOWN OR OTHER
Was sold Car Feb,27,2024 from dealership the car violently vibrates at 60mph took it to 3 Repair shops
NHTSA complaint #11596485 — an unverified report by a vehicle owner.
NHTSA complaint #11595996 — an unverified report by a vehicle owner.
Clovis, CACrash
STRUCTURE:BODY
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
Clovis, CACrash
ELECTRICAL SYSTEM
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
I am wanting to add information to my original complaint. Tracking#11589822 When I called in the electrical issue to AAA the agent said this is a common problem on these cars. Next, I want to add photos the Mercedes of Fresno service department sent me during the 2nd time my car was taken in to be checked. I honestly don't remember off hand when the collision occurred, I have that paper work somewhere. I will find it and send it in also. I will also get paper work from the auto body place that fixed as much of the wiring that it could. There was also a video on line I will try to find again and send that in.
NHTSA complaint #11591967 — an unverified report by a vehicle owner.
Oakley, CA
ENGINE
Car needs an engine rebuild at 90K miles due to a cracked piston #1, a problem with a car that received regular oil change intervals and proper service should not have
NHTSA complaint #11590907 — an unverified report by a vehicle owner.