Method for ensuring the safety of the components of the drive train of a vehicle following the deterioration of the fuel

A method for ensuring safety of components of a drive train of a vehicle equipped with a heat engine before or during a start up phase following a deterioration of quality of fuel contained in a tank and the fuel feed system of the engine, said method comprising:

• a step of diagnosing a type and extent of the deterioration of the quality of the fuel, said step of diagnosing comprising a step of determination of a molecular structure of the fuel, said determination being performed by a system of analysis, including at least one spectroscopic microanalyser;
• and
• a step of activating a system to ensure the safety of the components of the drive train as a function of the results of the analysis step,
• wherein the step of determination of said molecular structure of the fuel is based on an infrared spectroscopic analysis using said spectroscopic microanalyser.