Cooling liquid temperature sensor diagnostic method

The invention relates to the field of diagnostic method of automobile, in particular to a temperature diagnostic method of cooling liquid during the running of vehicles. The method adopts the following technical proposal: S1: an intake temperature sensor is used for collecting intake temperature signal values; a temperature sensor of the cooling liquid is used for collecting temperature signal values of the cooling liquid; S2: an ECU is used for comparing the temperature signal values collected by the S1 and the standard values of the temperature of the cooling liquid, and judging whether the temperature signal values are in the scale of the standard values of the temperature of the cooling liquid or in the scale of the boundary values of the standard values of the temperature of the cooling liquid; S3: if the temperature signal values are not in the scale of the standard values of the temperature of the cooling liquid or in the scale of the boundary values of the standard values of the temperature of the cooling liquid, the ECU can activate emergency processing procedures. The diagnostic method is implemented when the engine is running, and continuously monitors the temperature signals of the cooling liquid, so as to ensure the secure running of vehicles.