2026 Mercedes-Benz AMG C43 4MATIC Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2026 Mercedes-Benz AMG C43 4MATIC, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Electrical133.3%
- Engine133.3%
- Powertrain (other)133.3%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .