2020 Mercedes-Benz C300 Electrical system Problems
- Complaints
- 3about this part
- Share
- 9%of 33 total for the year
- Median mileage
- 6,000miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 3 complaints about the electrical system of the 2020 Mercedes-Benz C300, 9% of the 33 complaints for this model year. Where a mileage was given, the median is 6,000 miles. 1 of these say a crash was involved, according to the filers.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Vehicle has ongoing and recurring electrical and engine-related defects that affect safe operation. The primary systems involved are the electrical system, engine ignition system, and powertrain. The vehicle is available for inspection upon request. Prior service records show issues beginning in 2020 involving repeated electronic system failures requiring multiple repairs and component replacements. …”
NHTSA complaint #11733212, filed 2026-04“points: ⸻ While driving, the vehicle displays the warning “Active Brake Assist Functions Limited – See Operator’s Manual.” The message appears during normal driving and does not go away. This warning indicates that the automatic emergency braking / Active Brake Assist system is limited or disabled, reducing a critical safety feature designed to help prevent or mitigate collisions. This creates a safety risk because the vehicle may not automatically brake in an emergency situation. …”
NHTSA complaint #11710171, filed 2026-01“The contact owns a 2020 Mercedes-Benz C300. The contact stated that her son was driving at an undisclosed speed when another vehicle's muffler detached and crashed into the undercarriage of the contact's vehicle. The front driver and passenger side tires exploded and fractured the rims. The contact stated that the vehicle's alert system failed to warn her son of the incoming object which resulted in the collision. The contact's son did not receive medical attention. A police report was filed. The vehicle was towed to the dealer and repaired. …”
NHTSA complaint #11418528, filed 2021-05, 6,000 milesRelated service bulletins
- 11036511Aug 24, 2026Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket…
- 11036142Aug 12, 2026Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5…
- 11036190Aug 6, 2026Complaint A popup is seen on the HU with the message "data connection temporarily not available". Potentially affected functionalities in NTG4.5, NTG5 1.Weather 2.Local Search…
- 11033855Jun 12, 2026Complaint Service code B1 displayed in the customer menu does not match the workshop code displayed in the workshop menu, e.g., 505 or 550A, which includes a service A. Cause The…
- 11033185May 26, 2026Complaint After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the message "SOS - service not activated" appears on the…
- 11032699May 12, 2026Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5…
- 11030088Mar 9, 2026Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5…
- 11029927Mar 4, 2026Complaint Yellow information message in driver display (instrument cluster): "Switch on motor to charge the 12V battery" Cause The state of charge (SOC) of the 12V battery has…
- 11029093Feb 28, 2026Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5…
- 11028807Feb 14, 2026Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the engine control unit software does not correspond to current…
Electrical system: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2024 | 4 | 36% |
| 2023 | 5 | 23% |
| 2022 | 7 | 28% |
| 2021 | 1 | 7% |
| 2020 | 3 | 9% |
| 2019 | 13 | 19% |
| 2018 | 10 | 10% |
| 2017 | 31 | 14% |
| 2016 | 32 | 11% |
| 2015 | 50 | 13% |
| 2014 | 9 | 10% |
| 2013 | 19 | 7% |
| 2012 | 12 | 4% |
| 2011 | 43 | 9% |
| 2010 | 84 | 19% |
| 2009 | 198 | 34% |
| 2008 | 228 | 34% |
Other parts of the 2020 Mercedes-Benz C300
8 complaintsOther or unknown
5 complaintsBody and structure
4 complaintsForward collision avoidance
3 complaintsFuel system
3 complaintsTransmission and drivetrain
3 complaintsVisibility (wipers, defrost, mirrors)
3 complaintsAir bags
2 complaintsBack-over prevention (rear camera)
2 complaintsLatches, locks and linkages
2 complaintsSteering
2 complaintsTires
2 complaints
← All problems reported for the 2020 Mercedes-Benz C300
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 31, 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