Problems owners report
Complaints filed with NHTSA about the 2021 Mercedes-Benz C 300, by the system named in each complaint. One complaint can name several.
- Engine8
- Fuel/propulsion system2
- Back over prevention1
- Fuel system, gasoline1
- Power train1
- Air bags1
- Electrical system1
- Visibility1
NHTSA ODI complaints (public domain) · updated 23 Oct 2026 · 0 injuries and 0 deaths reported
Compared with other years
NHTSA ODI complaints by model year
Recalls
23V445000 · Fuel system, gasoline26 Jun 2023 · 143,551 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021-2023 C-Class, E-Class, S-Class, CLS, SL, GT, GLC, GLE, GLS, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle details. The fuel pump may shutdown, which can result in a loss of drive power.
22V365000 · Communication20 May 2022 · 242,722 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.
22V232000 · Back over prevention8 Apr 2022 · 126,443 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018-2021 CLA-Class, GLE/GLS-Class, A-Class, C-Class, E-Class, E-Class Coupe/Convertible, GLA/GLB-Class, GLC-Class, and CLS-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The rearview camera may not display the rearview image due to a software error. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
21V406000 · Seats28 May 2021 · 218 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C300 Cabriolet, C43 AMG Cabriolet, C63 AMG Cabriolet, C63 AMG S Cabriolet, E450 Cabriolet, and E53 AMG Cabriolet vehicles. The rear headrests may be incorrectly mounted to the seatbacks.
21V230000 · Seats1 Apr 2021 · 8,634 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C-Class, E-Class, E-Class Coupe and Convertible, GLC, CLS, AMG GT 4-door Coupe and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. A faulty electrical contact within the seat position switch may prevent the driver and passenger air bags and seat belt force limiters from properly activating during a crash.
21V058000 · Electrical system5 Feb 2021 · 1,292,258 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.
21V032000 · Seat belts29 Jan 2021 · 24,550 vehicles
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2021 C300, 2017-2020 AMG C43, and AMG C63 vehicles. The front seat belts might not fully retract to their stowed position. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 208, "Occupant Crash Protection."
Whether a recall was fixed on a particular car is known only to the manufacturer: check the VIN at nhtsa.gov/recalls.
NHTSA recalls · summaries in NHTSA's own words
Service bulletins
What Mercedes-Benz told its dealers about the 2021 Mercedes-Benz C 300: known faults, fixes and updates.
| Bulletin | Summary |
|---|---|
| 11010970 | Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY21-25 C-Class, CLA, EQB, EQE, EQS, G-Class, GLA, GLB, GLC, GLE, GLS, GT, S-Class, and SL (206, 118, 243, 294, 296, 465, 247, 254, 167, 192, 223, and 232 platform) vehicles, the MBUX multimedia system does not correspond with the latest series production configuration. The MBUX multimedia system control unit will receive an OTA software update. MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and installed in the customers vehicle free of charge and do n |
| 11010907 | Complaint The flap of the reversing camera opens and closes by itself during forward travel. This happens several times during the trip. The customer notices the sound of opening and closing. No camera image is displayed in the head unit. The reversing camera or the 360 system functions normally when activated manually or by engaging drive range "R". This behavior occurs again during each driving cycle. Cause This is not a malfunction, but an intended system behavior: Calibration of the reversing camera is in progress. For this, the cover on the camera is opened for max. 5 cumulative minutes i |
| 11010818 | Complaint Transmission control unit Y3/8n4 (fully integrated transmission control unit (VGS)) not listed in quick test and/or no communication possible with VGS. Cause Transmission control unit Y3/8n4 Remedy It is important that LI54.15-P-057373 is processed before replacing any component parts (transmission 722.9). After processing and complying with the above documents, perform a reset on the transmission control unit Y3/8n4 (VGS) (ignition reset), check that the transmission connector is seated correctly and inspect the PINs for concerns. If communication with the VGS cannot be established |
| 11010755 | Complaint After a control unit replacement of "N112/9 - control unit for telematics services (HERMES)" or the "N112/2 - control unit for telematics services (RAMSES)", the Digital Extras (previously Mercedes me) cannot be activated. The DTC B15CE00 is active or active+saved. In vehicles with "N112/9 - control unit for telematics services (HERMES)": The message "SOS - service not activated" permanently lights up in the instrument cluster AND the actual value "Error when replacing certificate (CEP.36)" is displayed in the actual values for the activation status under "Registration status" (see |
| 11010494 | Complaint Rear lamps fogged up/not leaktight. Cause Fogging of the rear lamps is a natural phenomenon, which can occur under certain climatic conditions. This does not lead to any technical impairment of the rear lamps. Remedy Rear lamp: Remedy 1: Clearing fogged/condensed rear lamps: 1. Drive the vehicle into the workshop (temperature higher than +18 C/+64.4 F) Note: Do not wash the vehicle or subject it to high-pressure cleaning before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the trunk. 4. Switch on the exterior lighting. 5. Leave the ve |
| 11010455 | Complaint Only vehicles with a variable transfer case are affected. Can be identified through control unit N45 or N15/7 in the quick test When accelerating with light load, vibrations or jolting sensation may come from the drivetrain Cause Modified oil quality of the transfer case over time Remedy Check initial quick test for faults in the following control units N45 - All-wheel drive (ARS) N127 - 'Drivetrain' (PTCU) control unit Y3/8 - Transmission control for 9-gear transmission (VGS) N3/10 - Engine electronics for combustion engine If faults are present, process them as per the guided test |
| 11009122 | Complaint Washer fluid system leaks Cause Various possible causes: 1. Washer fluid reservoir itself. 2. Seal on washer fluid pump/washer fluid reservoir. 3. Washer fluid pump. 3.1. Distributor housing leaks. 3.2. Pump fitting leaks. 3.3. Washer fluid hose cannot be snapped into place on pump fitting. 3.4. Washer fluid hose will not stay on pump fitting, although connector OK. 4. Washer fluid line. 4.1 Connector will not stay on pump fitting because it is broken. 4.2 Sealing ring in connector missing. 4.3 Sealing ring in connector fitted, but deformed and therefore leaks. 4.4 Damage to washer l |
| 11008880 | Complaint After a control unit replacement of "N112/9 - control unit for telematics services (HERMES)" or the "N112/2 - control unit for telematics services (RAMSES)", the Digital Extras (previously Mercedes me) cannot be activated. The DTC B15CE00 is active or active+saved. In vehicles with "N112/9 - control unit for telematics services (HERMES)": The message "SOS - service not activated" permanently lights up in the instrument cluster AND the actual value "Error when replacing certificate (CEP.36)" is displayed in the actual values for the activation status under "Registration status" (see |
| 11008873 | Complaint Tension-releasing impact of the propeller shaft with the force-free in D "KID" function, after vehicle has stopped. Cause The tension-releasing jolt in the drivetrain originates as a result of the "release" of energy stored when braking through the force-free switch after stopping. It is suspected that the longitudinal bearing is being placed under tension here as a result of the vehicle "dropping off". Remedy 1. Mark the installation position of the joint prior to the removal (picture a+b). This is important for vehicles with a weighted drivetrain ex factory to ensure correct instal |
| 11008712 | Complaint Check engine light on. One of the below fault codes is current in the engine control module (N3/10). P04DB29, P04DB31, P04DB79 Cause Open circuit or high resistance to crankcase vent line contact Remedy 1. Check the electrical connector for the relevant vent line contact switch noted below. Refer to attached photos of connection locations. 2. Ensure the bolted connection is secure and bolt can be torqued (9Nm). 3. Check continuity from vent line connection to ME control unit. Repair wire if damage is found. The circuit from ME provides 5V and is pulled to 0V when the ground connecti |
| 11008323 | Complaint Headlamps fogged or droplets forming. Cause Due to its outlet openings, the headlamp is an "open system". This means that acidic gases, moisture, dirt and exhaust gases can penetrate into the headlamp. This can lead to the formation of condensation on the lens of the headlamp. The headlamps comply with all applicable US standards and regulations. Remedy Check housing cover of lamp unit for natural fogging or condensation as per LI82.10-P-078301. If a reduction in the degree of fogging is visible, the desiccant packs can be used once the condensation has completely evaporated. Note: O |
| 11008091 | Complaint During a phone call, the called party has difficulty understanding/cannot understand the driver, or interference/background noises are audible to the called party during a call. It becomes increasingly difficult to understand as the speed rises. Cause A. Seating of the microphones in the headliner. Side edges are covered by the textile cover (see picture "1") B. Assembly of microphones (B25/20 or B25/21) in the headliner. C. Dirt inside the microphone housing Remedy 1. Press finger on rear of microphone (on adhesive tape) 2. Remove microphone cap from the front 3. Eliminate protrudin |
| 11008056 | Complaint Check engine light on. Fault code P207273 - "Throttle actuator valve is blocked due to ice" stored. Engine may crank and not start. Fault code P210185 may also be stored. Cause Moisture freezing on throttle actuator during extreme low ambient temperatures. Remedy Update software of engine control module. Software increases throttle valve flapping after engine turned off to prevent moisture buildup. |
| 11007974 | Complaint Headlamps leaking or fogged Cause The fogging of the headlamp is a natural phenomenon which can occur under certain climatic conditions. In contrast to a leaky headlamp, physical fogging does not result in a technical impairment of the headlamp. A leak test must be performed to determine if physical fogging exists or if the headlamp is leaky. Remedy In advance, observe LI82.10-P-078301 "Headlamps or Front Fog Lamps Leaking or Fogged". 1. Prepare headlamp/check for external damage: For headlamps with a closed system 1. Check the headlamps for any external damage and check also for cor |
| 11007790 | Complaint Headlamps fogged or droplets forming. Cause Due to the housing cover with pressure compensation diaphragm, the headlamps are a "closed system". This means that the headlamps are protected against acid gases, dirt and exhaust gas. However, moisture can still enter from two sources. Through absorption and desorption (the commonest cause) or through permeation. Moisture is either absorbed by the plastic material and, when the light source is switched on, it is released from the plastic by desorption, or the moisture penetrates through the plastic materials of the headlamp from outside |
| 11007753 | Complaint Headlamp or front fog lamp leaky or fogged Cause Fogging of the headlamps is a natural phenomenon, which can occur under certain climatic conditions. It does not lead to any technical impairment of the headlamp. Headlamps comply with all applicable standards. If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Remedy Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps and LED rear lamps: 1. Drive vehicle into workshop (temperature higher than +18 C/+64.4 F) and connect the exhaust extraction. Note: Do not perform an eng |
| 11007728 | Complaint To insure vehicle down time is kept at a minimum and all required information is available when case is escalated, as well as assist technicians with checks that may help lead in resolving issue without case creation. THIS LI IS NOT TO BE USED AS A REASON FOR CASE CREATION BUT AS A GUIDE IF A CASE IS NEEDED Cause There are, at times, additional steps workshops can do to help diagnose and rectify transmission complaints. Remedy When opening a case for transmissions a EEPROM, Quick Test, and VGS CUL are absolutely necessary Please also check for any relevant LIs before opening case. Al |
| 11006710 | Mercedes-Benz AG (MBAG), the manufacturer of Mercedes-Benz vehicles, has determined that on certain MY21-24 C-Class (206 platform), EQE (294 and 296 platform), EQS (295 and 297 platform), GLC (254 platform), AMG GT (192 platform), S-Class (223 platform), and AMG SL (232 platform) vehicles, the communication module software does not correspond with the latest series production configuration. The communication module will receive an OTA software update that includes product improvements. MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and install |
| 11005344 | Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic / 9G-TRONIC automatic transmission) and 725.1 (NAG3 facelift/9G-TRONIC automatic transmission facelift) For faster, more effective and more targeted diagnosis, Intelligent Predictive Repair (IPR) has been developed and integrated into XENTRY Diagnosis. This ensures an automated diagnosis process. Cause As part of the on-going quality monitoring process and associated quality and damaged part appraisals, a high number of ineffective repairs have been discovered. Such ineffective repairs have a negative impact o |
| 11005331 | Complaint Only vehicles with a variable transfer case are affected. Can be identified through control unit N45 or N15/7 in the quick test When accelerating with light load, vibrations or jolting sensation may come from the drivetrain Cause Modified oil quality of the transfer case over time Remedy Check initial quick test for faults in the following control units N45 - All-wheel drive (ARS) N127 - 'Drivetrain' (PTCU) control unit Y3/8 - Transmission control for 9-gear transmission (VGS) N3/10 - Engine electronics for combustion engine If faults are present, process them as per the guided test |
| 11005314 | Complaint Yellow Coolant warning comes on in cluster Fault codes below are current or stored in MED41 P0A0500- The actuation of the circulation pump for the low-temperature circuit has an open circuit. P00B700- The coolant flow is too low. P0C7300- Circulation pump 1 for the low-temperature circuit has a malfunction. Cause Air may be trapped in the coolant circuit for transmission cooler Remedy Check coolant level. -If coolant level is low, locate source of leak and correct. -If coolant level is ok, perform procedure in attached instructions to bleed the coolant circuit to transmission cooler. |
| 11005313 | Complaint Check engine light on and fault code P019185 current or stored in MED41 control unit. Adaptation and misfire faults may also be stored. Vehicle may enter limp home mode. Cause False detection of rail pressure sensor out of range. Remedy Update software of engine control module N3/10. Reset mixture adaptation and clear fault codes. |
| 11005294 | Complaint Rear lamps fogged up/not leaktight. Cause Fogging of the rear lamps is a natural phenomenon, which can occur under certain climatic conditions. This does not lead to any technical impairment of the rear lamps. Remedy Rear lamp: Remedy 1: Clearing fogged/condensed rear lamps: 1. Drive the vehicle into the workshop (temperature higher than +18 C/+64.4 F) Note: Do not wash the vehicle or subject it to high-pressure cleaning before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the trunk. 4. Switch on the exterior lighting. 5. Leave the ve |
| 11003218 | Complaint Complaints about shift quality in vehicles of MODEL 205, 212 and 222 with TRANSMISSION 724.2. Cause If the shift adaptation is not performed as described under "Remedy", the adaptation values may not be saved correctly under certain circumstances. Remedy In vehicles of MODEL 205, 212 and 222 with TRANSMISSION 724.2, it must be ensured that the adaptation of the shifts is performed only as described below. Acceleration upshifts may only be adapted in transmission mode "S" Acceleration downshifts may only be adapted in transmission mode "S" Coast down shifts may only be adapted in t |
| 11003212 | Complaint Noticeable vibrations at the steering wheel: At speeds between 40mph and 75mph On straight stretches of road and in long corners With driver assistance systems switched on Cause Control oscillations in the electric power steering. Remedy Perform software update of electric power steering (N68). Note: Please ensure newest Xentry release software is installed and all addons are updated. After the software update, teach in the steering limitations of the electric power steering again: 1. Start engine 2. Turn steering wheel all the way to the left and briefly hold at the steering limi |
NHTSA manufacturer communications (public domain)