2018 Mercedes-Benz C300 Other or unknown Problems
- Complaints
- 23about this part
- Share
- 23%of 99 total for the year
- Median mileage
- 30,000miles
- Trend
- RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
NHTSA recorded 23 complaints about the other or unknown of the 2018 Mercedes-Benz C300, 23% of the 99 complaints for this model year. Where a mileage was given, the median is 30,000 miles.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Forward collison system ($1700 option) aeb, does not work as described in mb literature or website. In my opinion, the forward collision avoidance system (aeb) in my 7 mo. Old 2018 mercedes C300 simply does not work. I special ordered the car with the 997 pkg that includes, driver assistance, bas+, and distronic the mb manual states: 'if active brake assist detects that there is a risk of collision, you will be warned visually and acoustically. …”
NHTSA complaint #11163276, filed 2018-12, 5,000 miles“My c300 2018 only has 50k and suddenly the engine light is on, when I check it shows that I need the Positive Crankcase ventilation valve replaced. it cost $2300. As I know a lot of people who own Mercedes have the same problem. Three mechanics claim it on almost all C, CLA, and GLA models. Please make Mercedes recall it finally.”
NHTSA complaint #11533877, filed 2023-07“The sunroof on the vehicle jams and either stays partially open or won’t close in the rear completely. I finally got it to close but it will not open again. I know multiple mercedes owners who have this issue with the sunroof and if the sunroof will continue to not lock properly this could be a hazard on the highway if the brackets were to break and the glass slides off.”
NHTSA complaint #11446466, filed 2022-01“There are Water intrusion that happened to other Model of Mercedes, my car have the same problem, when i bring it to the Mercedes dealer, they found a lot of water inside the trunk, but they insisted that I had accident, but there no accident that I know of.”
NHTSA complaint #11570616, filed 2024-02“To Whom It May Concern, I bought this certified preowned Mercedes Benz, and the recall is open. I have taken the car to the dealership, they deny me from service because its an over the air recall. The Mercedes Benz website clearly states on their letter for consumer that the remedy for this recall can be taken care at the dealership free of charge or an over the air update. Its July and I got the car back in February.”
NHTSA complaint #11423935, filed 2021-07Related service bulletins
- 11035780Aug 4, 2026Complaint Mercedes-Benz USA is currently experiencing limited availability of transmission fluid specification ATF 236.17 due to a global supply constraint. 236.17 ATF 1L and 5L…
- 11028809Feb 13, 2026Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the TIREFIT sealant bottle may not meet specifications. The…
- 10179966Jul 31, 2020Incorrect time and/or instrument cluster message "SOS, service not activated" and/or Mercedes Me connect services nonfunctional
- 10205156Aug 26, 2016Intial startup not possible after replacement of transmisson 725.0 or of electrohydraulic controller unit.
- 10205154Aug 5, 2016Gasket may settle causing a slight oil leak.
Other or unknown: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2024 | 3 | 27% |
| 2023 | 4 | 18% |
| 2022 | 2 | 8% |
| 2020 | 5 | 15% |
| 2019 | 10 | 14% |
| 2018 | 23 | 23% |
| 2017 | 36 | 17% |
| 2016 | 65 | 22% |
| 2015 | 63 | 17% |
| 2014 | 8 | 9% |
| 2013 | 19 | 7% |
| 2012 | 23 | 9% |
| 2011 | 33 | 7% |
| 2010 | 27 | 6% |
| 2009 | 31 | 5% |
| 2008 | 38 | 6% |
Other parts of the 2018 Mercedes-Benz C300
34 complaintsBody and structure
14 complaintsSteering
12 complaintsElectrical system
10 complaintsFuel system
10 complaintsAir bags
4 complaintsForward collision avoidance
4 complaintsVisibility (wipers, defrost, mirrors)
3 complaintsBrakes
2 complaintsExterior lighting
2 complaintsTires
2 complaintsTransmission and drivetrain
2 complaints
← All problems reported for the 2018 Mercedes-Benz C300
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Nov 1, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology