Mercedes-Benz Trouble Codes and Known Issues

Mercedes-Benz uses four and six-cylinder gasoline engines with variable valve timing and CDI common rail diesels. The electronics are very extensive and many codes need a scan tool that can reach every module.

Most searched models: A-Class, B-Class, C-Class, E-Class, CLA, GLA, GLC, ML / GLE and Sprinter.

Common problems on Mercedes-Benz vehicles

• Camshaft adjusters and timing chain on the M271 and M272 engines (2000s).
• Thermostat and temperature sensors.
• Injectors and rail pressure on CDI diesels and the Sprinter.
• Conductor plate on the 7G-Tronic (722.9) automatic transmission, with built-in speed sensors.

Tips for diagnosing a Mercedes-Benz

• On the 7G-Tronic, several transmission speed codes point to the conductor plate, not to separate sensors.
• Use oil that meets the specified MB approval (229.5, 229.51 and so on).

Do you have several codes at once? Use the free multi-code diagnosis for Mercedes-Benz: it sorts the codes by priority and shows these make-specific notes. Below are the codes with documented quirks on Mercedes-Benz vehicles.

Make notes are a guide based on well-known common failures. Always confirm with the manufacturer's documentation for your engine and model year.