2026 Mercedes-Benz AMG C43 4MATIC

CEL followed by no crank / no start. Codes u3017 and u0168. Software flashed and no crank / no start returned. SAM & EIS modules replaced and no crank/no start returned with new codes. U103F00 + P143400 + P051300. Now Mercedes is directing the replacement of the ethernet harness between the SAM and EIS. This intermittent communication or electrical fault can cause the vehicle to unexpectedly lose the ability to start. This creates a safety concern because the vehicle could fail to restart after being stopped in traffic, at an intersection, at a fuel station, or in another location where reliable starting is necessary. The intermittent nature of the failure also makes it difficult to predict when it will occur. The vehicle has sometimes operated normally for extended periods and then unexpectedly failed to start. As of filing this report the issue remains unresolved.

NHTSA ID

11760695

Incident

Aug 22, 2026

Complaint Diverse functional limitations in the vehicle in combination with various warning and fault messages in the instrument cluster display. Cause Communication timeouts mean that communication errors may occur in the on‑board electrical system, which can result in various fault messages being displayed in the instrument cluster. This could be down to delayed feedback from the drivetrain control unit (N127) (CPC) to other control units networked to the CAN bus. Information: Only valid for vehicles through production period 10/2025. Not valid for vehicles with control unit CDCC (N125, central controller charging and driving) • It may not be possible to attribute any communication errors stored in the control units on the CAN bus to a specific cause • In rare instances, there may be a brief activation of the yellow warning lamp for engine diagnosis or there may be a sporadic delay with the start enable. • There may not be any specific fault codes present that indicate a specific component. Example image: Fault messages in instrument cluster: The reason for this could be down to delayed feedback from the control unit CPC3 to other control units networked on the CAN bus. Remedy Do not replace any components!!! ******************************************************************************************************* 1. Connect charger (see AR54.10‑P‑1127WT). Note: An adequate voltage from the on‑board electrical system battery must be guaranteed for the entire duration of the work procedure. Otherwise, the control units could be damaged if an undervoltage occurs. Information: Observe the operating instructions of the charger. Information: Use the charger to ensure an adequate voltage (at least 12.5 V) from the on‑board electrical system battery. ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑ 2. Connect diagnostic system (see AD00.00‑P‑2000‑06FR). Note: Always use the latest XENTRY Diagnostics software release. Information: Strict compliance with the operation steps in XENTRY Diagnostics is absolutely essential. ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑ 3. Select control unit N127 (CPC) via the direct link using XENTRY Diagnosis. Information: To do so, select the following menu items: Control units view → Drive systems → N127 ‑ "Drivetrain" control unit (CPC) ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑ 4. Update software for control unit N127 (CPC) (see AR54.21‑P‑0014‑01Y). Info: To do so, select the following menu items: Adaptations → Control unit update → Update control unit software. Information: You are then automatically guided through the steps "Update of control unit software" and "SCN coding". Always observe the following operation steps at all times ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑ 5. Disconnect diagnostic device from vehicle (see AD00.00‑P‑2000‑06FR). ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑ 6. Disconnect charger from vehicle (see AR54.10‑P‑1127WT).

Issue Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, is launching an OTA update to the subject vehicles to provide an enhanced user experience. This OTA update includes enhancements to the MBUX voice assistant. Remedy MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and installed in the customer’s vehicle free of charge and do not require a dealer visit.

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 damper oil • Squeaking noises: From the mechanical rubber valve in the dividing piston Remedy In case of complaints, the front shock absorbers must be replaced. If shocks have been replaced and noise persists, please open a TIPS case to the Body, Chassis, Entertainment inbox.

Issue A software update will be performed that provides enhancements to the robustness and system stability of the communication module. The update is free of charge and runs in the background, which takes about 8 minutes to install. During this time, the vehicle can be driven without any restrictions, and the new software will be active with the next ignition cycle. Remedy MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and installed in the customer’s vehicle free of charge and do not require a dealer visit.

Complaint Slight creaking noises when steering. Cause Noises may come from one or more sleeves of the horn contact plate. Remedy Remove the horn contact plate and check the sleeves for noise; see attached video. If necessary, apply lubricant to the sleeves.

Complaint CEL illuminates and/or AC does not blow cold. Cause Potentially relevance to hardware and/or software Remedy Scenario 1: 1. If the AC does not blow cold air, replace compressor (if compressor's index and part number Figure 1 match against Table 1). a. If the compressor does not fall within Table 1, please open a TIPS case. b. Flush procedure must be followed as per WIS. Scenario 2: 1. If AC does blow cold. a. Follow the following procedure: i. Have the air conditioning system recharged. ii. Clear the fault codes afterward. iii. Let the vehicle stand for 8 hours (OBD reset condition). iv. Check whether the fault is still present. b. Open TIPS case with your findings and answers the following questions, send to the HV/LV inbox. i. When exactly did the MIL appeared (immediately at start‑up or while driving). ii. What was the ambient temperature, any special driving maneuvers, and whether the vehicle had just come out of a climate‑controlled garage.