2023 Mercedes-Benz C300 Technical Service Bulletins

359 technical service bulletins (TSBs) are on record for the 2023 Mercedes-Benz C300. TSBs are notes manufacturers send to dealers about repair procedures for issues seen in the field. They are not recalls and do not by themselves mean a vehicle has a fault.

• 11027905Jan 30, 2026Suspension. Complaint: Clattering noise from area of hood with steel suspension. Cause: Missing helical spring shim (blue part as shown in attached picture "Helical Spring Shim"). Remedy: Check whether the blue helical spring shim is installed. If NOT present: Install the spring shim. Replacement part is black. If present: Replace the blue shim with the aftersales part black shim. If noise is still not remedied after replacing…
• 11027904Jan 30, 2026Electrical system, Back-over prevention (rear camera). Complaint 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. Cameras 6. Other Park Topics Cause Various root causes Remedy See attached diagnostic guide.
• 11027820Jan 26, 2026Electrical system. Complaint The vehicle's position on the map is displayed far away from its actual position, e.g. the vehicle is displayed as being in the middle of the ocean. Note: No relevant DTC is displayed during the quick test. Cause The GNSS antenna is not correctly inserted at the GNSS connection (see picture in the attachment) in the head unit (A26/17). Remedy Insert the plug into the GNSS connection and ensure that the…
• 11028003Jan 23, 2026Engine. Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA is extending the warranty coverage on the exhaust valve system in your vehicle from the original New Vehicle Limited Warranty of 4 years/ 50,000 miles to 15 years/ 150,000 miles (whichever occurs first). This applies to the vehicle…
• 11027796Jan 23, 2026Steering. Complaint Noises from the area of the steering column. - Creaking - Squeaking - Chattering - Humming - Grinding Cause At present, there are no known noise problems with the steering column. Remedy Check surrounding area of the steering column for possible noises. • Instrument panel support • Steering column switch module If noise only occurs when adjusting the steering column via electric actuation please perform…
• 11027782Jan 21, 2026Other or unknown. Complaint The intent of this document is to provide workshops with helpful technical reference language. • Commonly used acronyms in LI's and TIPS cases. • Control unit names, numbers, and how to identify. • Network/wiring architecture groups to baumuster quick reference. • Platform to baumuster quick reference.
• 11027751Jan 16, 2026Visibility (wipers, defrost, mirrors). Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy *Note - This Li does not apply if there are other Li's that apply to your concern OR you have a fault and/or guided test that leads to a root cause. AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle…
• 11027682Jan 15, 2026Visibility (wipers, defrost, mirrors). Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle • Determine if the behavior is normal by comparing with a similar vehicle. Determine Your Game and Players • Identify the diagnostic strategy and…
• 11027656Jan 14, 2026Electrical system. Complaint For the potentially affected vehicles, excessively high aging of the battery was calculated at cold battery temperatures (<10°C) and the MIL activated accordingly, even though there is no corresponding high level of aging physically. In this regard, the fault code P0A7F00 "The age limit of the hybrid/high-voltage battery module has been reached" is displayed in the N127 PTCU control unit and/or A66…
• 11027583Jan 10, 2026Electrical system. Complaint After the charging process is complete, an instrument cluster message with a charging error appears and FC P0CFE00 is stored in control unit "N83 - AC charger for high-voltage battery (SG-LG)". The instrument cluster message and the FC memory entry can also appear at the beginning of the charging pause during delayed charging. Both only occur in combination with active pre-entry climate control. Cause…
• 11027580Jan 10, 2026Engine. In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA, LLC is extending the warranty coverage on the exhaust valve system in certain Model Year (MY) vehicles listed below from the original New Vehicle Limited Warranty of 4 years/50,000 miles to 15 years/150,000 miles, whichever occurs first.
• 11027566Jan 7, 2026Visibility (wipers, defrost, mirrors). Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle • Determine if the behavior is normal by comparing with a similar vehicle. Determine Your Game and Players • Identify the diagnostic strategy and…
• 11026833Dec 20, 2025Transmission and drivetrain. Complaint (Original LI document #: LI27.35-P-079039) Clicking noises from the electro-hydraulic control unit (EHS) when the vehicle is stationary and ECO Start/Stop is active (combustion engine is off). The noise is more noticeable outside the vehicle and in acoustically shielded areas such as closed rooms or garages. Cause The noise in the valve body (EHS) is caused by superimposed pressure peaks acting on the…
• 11026835Dec 18, 2025Electrical system. Complaint The flap of the reversing camera opens and closes by itself during forward travel several times during the trip. 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". Cause This is not a malfunction, but an intended system behavior. Calibration of the reversing camera is in progress.
• 11026834Dec 18, 2025Electrical system. Complaint After the charging process is complete, an instrument cluster message with a charging error appears and FC P0CFE00 is stored in control unit "N83 - AC charger for high-voltage battery (SG-LG)". The fault message and the fault memory entry can also appear at the beginning of the charging pause during delayed charging. Both only occur in combination with active pre-entry climate control. Cause Software in…
• 11026829Dec 18, 2025Engine. Complaint Engine idle fluctuates or stumbles at approximately 7 second interval. No relevant fault codes are stored. If fault codes are stored or check engine light illuminated, this should be diagnosed separately. Cause Torque signal mismatch between MRG and PTCU control units. Only effects version 20B of PTCU. Remedy Update software of powertrain control unit N127. New software version: MY 2022- A2549021611 MY…
• 11026607Dec 12, 2025Electrical system. Complaint The following most common complaints may be observed: • Brief connectivity interruptions when using Apple CarPlay over Wi-Fi • Audio cuts out • Device not recognized • No operation possible Cause There are multiple possible causes for an iPhone disconnecting from a vehicle’s head unit while using Apple CarPlay.
• 11026611Dec 11, 2025Electrical system. Complaint 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. Cameras 6. Other Park Topics Cause Various root causes Remedy See attached diagnostic guide.
• 11026127Dec 3, 2025Electrical system. Complaint Displayed Message: “Driver camera not functioning, see Operator’s Manual” Cause Interior temperature too high due to: • Summer heat • Direct sunlight • Lack of air conditioning or ventilation Camera enters self-protection mode to prevent overheating. Remedy Do NOT replace any parts. The driver camera (NTG7: MDC295; CIVIC.i2: CIVIC206) is operating as designed. Allow the interior to cool down.
• 11026026Dec 2, 2025Electrical system. Complaint After the charging process is complete, an instrument cluster message with a charging error appears and FC P0CFE00 is stored in control unit "N83 - AC charger for high-voltage battery (SG-LG)". The fault message and the fault memory entry can also appear at the beginning of the charging pause during delayed charging. Both only occur in combination with active pre-entry climate control. Cause Software in…
• 11025646Nov 18, 2025Electrical system. Complaint USB port not functioning properly. Cause Most reported USB port issues are due to improper use or contamination. Note: Any repair costs must be discussed with the customer beforehand. Common external factors identified include: • Fluid intrusion • Broken bushings or physical damage See attachments. Remedy If a component needs replacement but shows no visible external damage, submit a detailed TIPS case…
• 11025560Nov 17, 2025Transmission and drivetrain. Complaint The shift from 1st to 2nd gear may be uncomfortable under light load. Cause Vehicles with engine M264 and transmission 725.0 may be equipped with specific software versions. Remedy Update Transmission Software (VGSNAG3). 1.
• 11025648Nov 15, 2025Transmission and drivetrain. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to micromovement in the connection between the wheel bearing inner…
• 11025471Nov 10, 2025Transmission and drivetrain. Complaint Possible complaints about shift quality, issues with learning the park lock, and slipping/rinse entries in the EEPROM or Transmission Health system following the replacement of the below components: - The electrohydraulic control unit (EHS valve body) in transmission 725.0/725.1 - The repair kit for the control unit (VGS) in transmission 725.0 Cause Missing, incorrectly installed, or damaged guide tubes…
• 11025544Nov 6, 2025Electrical system. Complaint USB port not functioning properly. Cause Most reported USB port issues are due to improper use or contamination. Note: Any repair costs must be discussed with the customer beforehand. Common external factors identified include: • Fluid intrusion • Broken bushings or physical damage See attachments. Remedy If a component needs replacement without visible external damage, submit a detailed TIPS case.
• 11025536Nov 5, 2025Transmission and drivetrain. Complaint Harsh 2-1 downshifts when coming to a stop with ECO start-stop function turned OFF. Note: When ECO start-stop is active, the engine is shut off before the 2-1 shift and the complaint will not occur. Cause Software application when engine is running. Remedy Short-term remedy: Perform IPR and follow the instruction to perform standstill adaptations. Long-term Solution: Aftersales software is currently in…
• 11025150Nov 5, 2025Transmission and drivetrain. Complaint A harsh 5-4 downshift can be felt during deceleration while braking or coasting. It may be mistaken for a hard brake engagement Cause Poor learning of brake B06 adaptation values over time. Remedy Short-term remedy: 1. Perform IPR and follow the instructions. 2. Perform resetting of deceleration values (VGS > Special Procedures > Special procedure > Resetting learned values Deceleration mode) 3. Perform…
• 11025100Nov 3, 2025Transmission and drivetrain. Complaint Only vehicles with a variable transfer case are affected. This 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. It may be mistaken for a harsh shift. Cause Modified oil quality of the transfer case over time Remedy 1. Check initial quick test for faults in the following control units.
• 11024426Oct 24, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the door control unit software does not correspond to current production specifications. In this case, the 12V starter battery may sporadically discharge. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the door control unit software.
• 11024405Oct 20, 2025Brakes. Complaint At low speeds and light brake pressure, brakes will make a groaning or honking noise. Cause Frictional vibrations with very light brake pressure/modulations. Remedy This condition can be duplicated on most vehicles. To validate, use a like for like reference vehicle. The noise is normal behavior under the conditions listed. With very light brake pressure this noise can be induced/caused due to normal…
• 11024276Oct 10, 2025Seats. Complaint The "Easy entry and exit feature" function deactivates itself after a brief period. (see attachment). Cause The cause is currently being investigated. Remedy Update the HU7 to the latest software version, then perform a factory reset of the HU7. Steps to perform factory reset: Navigate to Settings > System > Reset > Reset to factory settings and confirm.
• 11024274Oct 10, 2025Electrical system. Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment.
• 11023347Sep 25, 2025Electrical system. Complaint The result from the XENTRY battery test does not match the current state of the battery. Cause The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM or EZS cannot record the data if the battery is discharged. Note: A discharged…
• 11023193Sep 17, 2025Transmission and drivetrain. 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 For vehicles with 722.9 transmission: Ensure LI54.15-P-057373 is performed before replacing any component parts. After processing and complying with the above document(s): 1. Perform an ignition reset on Y3/8n4…
• 11023190Sep 15, 2025Body and structure. Complaint Seal secured to B-pillar trim on rear doors cracked in upper area, see picture 1. Cause Production deviation at supplier of B-pillar trim. Remedy Replace both B-pillar trims with optimized parts. Note: Both B-pillar trim pieces on the vehicle should be replaced, even if only one currently has the complaint.
• 11023107Sep 13, 2025Electrical system. Issue Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the High Voltage Battery (“HVB”) AC charger software does not correspond to current production specifications. As a consequence, a HVB MIL may illuminate during charging due to fluctuations in power consumption of the charging socket actuator. Remedy MBUSA will conduct a service campaign. An…
• 11023153Sep 11, 2025Electrical system. Complaint After the charging process is complete, an instrument cluster message with a charging error appears and FC P0CFE00 is stored in control unit "N83 - AC charger for high-voltage battery (SG-LG)". The fault message and the fault memory entry can also appear at the beginning of the charging pause during delayed charging. Both only occur in combination with active pre-entry climate control. Cause Software in…
• 11023047Sep 5, 2025Electrical system. Complaint The Apple Music app is no longer available in the head unit apps menu after updating the software of the (A26/17 - MBUX multimedia system + instrument cluster (head unit)) to E333.8 / A236 904 19 00. Cause Head unit software (CIVIC206) Remedy NOTE: Do not replace any component parts A remedy is currently being developed and will be communicated once finalized. Once service is restored, the app will be…
• 11023026Sep 4, 2025Electrical system. Complaint No audio is output either in radio mode, or with media playback via app, Bluetooth or USB. In such cases, "Playback not active" is shown in the display. Cause Mute line between communication module N112/2 and sound control unit N40/3. Remedy Check the mute cable between control units N112/2 (communication module) and N40/3 (sound system). • Inspect the cable and plug contacts for damage or deformation. •…
• 11022842Sep 4, 2025Suspension. Complaint Metallic clattering/noise from the area of the dashboard on uneven roads Cause A loose upper metal plate in the head bearing (support bushing) causes the noises. Remedy 1 - Check for loose metal plate by tapping your finger against the metal plate in the head bearing. See video "Rattling Noises" for reference. Metallic noises audible? • Yes: Replace head bearing (support bushing). • No: Replace…
• 11023024Sep 3, 2025Exterior lighting. Complaint Message in instrument cluster "Adaptive high beams assistant not available/inoperative" or "DIGITAL LIGHT reduced range of functions" in relation to "FC151E29- The level sensor at front left has a malfunction. There is an invalid signal" in the control unit HLI/LED headlamp range adjustment front left. (HLI_FL223 HW: A2239017717/ HWVersion: 23.11.00) Cause Electronic interference occurring at the sensor…
• 11022529Aug 29, 2025Suspension. Complaint Wheezing noises/squeaking noises from the front shock absorbers when passing over surface undulations and rough road. Noise MUST match those heard in the attached videos. Cause • Wheezing noises: Flow noises of the shock absorber fluid • Squeaking noise: From the mechanical rubber valve in the dividing piston Remedy Replace shock absorber(s).
• 11022528Aug 29, 2025Suspension. Complaint Clattering noise from area of hood with steel suspension. Cause Missing helical spring shim (blue part as shown in attached picture "Helical Spring Shim"). Remedy Check whether the blue helical spring shim is installed. • If NOT present: Install the spring shim. • If present: Provide sound/video file with matching noise, verification of no installed spring shim via picture, and open a TIPS case…
• 11022204Aug 29, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the charging function does not correspond to the current series production configuration. The charging system software will be updated to stabilize the charging function of the vehicle. MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and installed in the…
• 11022385Aug 28, 2025Electrical system. Complaint Message in Instrument Cluster for "Active Distance Assist not enabled, but can be purchased subsequently" even if Digital Extra: Active Distance Assist DISTRONIC (207) has already been activated/purchased via the application. Cause On some vehicles with Digital Extra: Active Distance Assist DISTRONIC (code 207), it may be that the function cannot be enabled via the application or is no longer available in…
• 11022056Aug 5, 2025Steering. Complaint Valeo Steering Column Module (N80) goes into bootloader after updating software to A2239028729. To verify the supplier and software number of the steering column module. See attachment "Supplier Identification" for assistance. Cause MRSM/SCCM flashed to SW A2239028729 Remedy Please send VIN specific ID1 Support Package online using the XENTRY Kit used during the time the error occurred. Then, create an…
• 11022055Aug 5, 2025Steering. Complaint Criteria: • Customer concern for ESP/Brake or Steering yellow instrument cluster message. • DTC's C220564 or P161447 in the Steering Column Control Module (N80). • N80 supplier is "BCS". • "Hardware" or "Boot Software" version number is 23/18 000 or greater. To check which supplier steering column module is in the vehicle and where to find the hardware version number. Please see attachment, "N80 Control…
• 11022050Aug 5, 2025Suspension, Steering. Complaint Customer concern for ESP/Brake or Steering yellow instrument cluster message AND C220564 in the N80 Steering Column Control Module (Valeo Parts only). To check which supplier steering column module is present in the vehicle, see attachment "Supplier Identification". Cause Triggered due to communication related software timing. Remedy New software A2239026336. Update N80 (Steering Column Module) to target…
• 11021140Aug 2, 2025Electrical system. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the SRS control unit software does not correspond to current production specifications. The SRS control unit will be updated to improve the vehicle charging functionality during future over-the-air updates. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the SRS…
• 11021154Jul 31, 2025Seats. Complaint The customer complains about squeaking/creaking noises on uneven roadways, on bends or when moving in their seat. Cause Noise in the backrest adjustment mechanism Remedy The adjustment mechanism is treated with dry lubricant spray A000 989 35 60 to rectify the noise. To do this, proceed as follows: • Move the seat to the front position and put the backrest into a lying position.

← All problems reported for the 2023 Mercedes-Benz C300