2021 Mercedes-Benz C 300 4matic technical service bulletins
49 technical service bulletins and manufacturer communications cover the 2021 Mercedes-Benz C 300 4matic, including 3 warranty extensions.
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz...
- Fuel/propulsion system
- In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the...
- Customer complaints relating to automatic transmission 725.0 (NAG3 Classic /9G‑TRONIC automatic...
- Slight creaking noises when steering
- CEL illuminates and/or AC does not blow cold
- Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE: Although the symptom is...
- Only vehicles with a variable transfer case are affected
- Clanking noise from the area of the speakers in the doors
- Customer complaints relating to automatic transmission 725.0 (NAG3 Classic / 9G‑TRONIC automatic...
- During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time
- Tailgate opens unintentionally
- 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active...
- A popup is seen on the HU with the message "data connection temporarily not available". Potentially...
- This document is intended as a pre-case diagnostic reference for transmission related concerns
- Mercedes-Benz USA is currently experiencing limited availability of transmission fluid specification ATF...
- Engine
- Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end)
- Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed,...
- Service code B1 displayed in the customer menu does not match the workshop code displayed in the workshop...
- After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the...
- Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed,...
- There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper...
- The part numbers listed in the chart below should no longer be installed, and any existing stock must be...
- 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active...
- Damaged cords/tensioning cables at the soft top interior trim with the following characteristics
- Headlamp, front fog lamp leaky or fogged
- -Check engine light illuminated
- The intent of
- The seat may no longer be adjustable using the electric seat adjustment switch on the door module
- Yellow information message in driver display (instrument cluster): "Switch on motor to charge the 12V battery"
- Headlamp, front fog lamp leaky or fogged
- Engine
- Unknown or other
- Check engine light on with the following fault is current in the VGS Control Unit: P084300 Oil pressure...
- The vehicle cannot disengage “P” (Park), and a red warning message appears in the instrument cluster
- Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz...
- Customer states the AC either does not cool/has poor performance or heat is insufficient
- (Original LI document #: LI27.35-P-079039) Clicking noises from the electro-hydraulic control unit (EHS)...
- The following most common complaints may be observed: • Brief connectivity interruptions when using Apple...
- Displayed Message: “Driver camera not functioning, see Operator’s Manual”
VIN decoder
See the problems and recalls for an exact car
Buying a used 2021 Mercedes-Benz C 300 4matic?
Check the exact car before you pay: accidents, salvage or flood titles, odometer readings and previous owners.
Check its history