Fault Diagnosis Method and Diagnosis System of Engine Temperature Control Module

Abstract

A fault diagnosis method for an engine temperature control module, comprising: judging whether the system voltage is within the allowable range in the normal working mode of the temperature control module; if the system voltage is outside the allowable range, outputting a fault code, and Take corresponding countermeasures; if the system voltage is within the allowable range, calculate the equivalent voltage based on the system voltage, and judge whether the current equivalent voltage is less than the set safety threshold; if the current equivalent voltage reaches or exceeds the safety threshold, It is further judged whether the continuous working time of the temperature control module exceeds the limit time; if it exceeds the limit time, the action of the ball valve is forcibly stopped, and the rotation of the ball valve is continued after waiting for the set time. The invention also provides a fault diagnosis system of the engine temperature control module.

Description

technical field [0001] The invention relates to an engine water cooling system, in particular to a fault diagnosis method and a diagnosis system for an engine temperature control module. Background technique [0002] At present, the commonly used engine cooling system on the market usually includes a mechanical water pump and a thermostat. The physical structure of the thermostat is mainly based on the wax pack. When the water temperature is low, the wax pack is solid. The thermostat valve closes the branch of the coolant leading to the radiator under the action of the spring. When the water temperature is high, the wax pack melts into a liquid. , the volume increases accordingly, push the thermostat valve to open the radiator branch to cool down. This structure determines that the engine cooling system can only be switched in two states of a large cycle (with the radiator participating) and a small cycle (with the radiator not participating), and cannot control more branch...

AI Technical Summary

Problems solved by technology

However, traditional thermostats cannot perform self-diagnosis, and if self-diagnosis is required, an additional water temperature sensor needs to be combined

That is, it is necessary to judge whether the value of the main water temperature sensor has risen normally over time. After it rises to the melting threshold of the thermostat wax bag, it is also necessary to combine the auxiliary water temperature sensor to judge whether the water temperature in the current radiator passage has a normal change. To judge whether the thermostat can be opened or closed normally, in addition, it is also necessary to judge whether the water temperature is normal based on the current vehicle working conditions, that is, the thermostat cannot complete this process by itself, and needs to rely on other components through complex control strategies To realize the diagnosis, especially in the condition of the engine not working on the hybrid model, the complexity of this strategy will increase significantly

Furthermore, since the traditional thermostat only has two states of on or off, the ECU cannot judge the intermediate state. Once a fault causes the water temperature to be too high, it often only makes the whole vehicle limp.

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