Fault diagnosis device and method for vehicle solenoid valve

The invention discloses a fault detection device and a diagnosis method for a vehicle solenoid valve. The fault detection device comprises a controller, an internal short circuit fault detection circuit, an open circuit and power supply short circuit fault detection circuit, a ground short circuit fault detection circuit, a power module, a first sampling module, a vehicle solenoid valve, a first control switch M1 and a second sampling module. The detection and diagnosis faults include ground short circuit fault, open circuit fault, power supply short circuit and internal short circuit fault and reliability fault of the solenoid valve, etc. The fault of the solenoid valve is mainly judged by a reasonably designed hardware circuit and an accurately developed software. The diagnosis method is used respectively before and when the electronic fuel injection engine is started, so as to ensure whether the fault occurs to the solenoid valve and take corresponding protective measures. Therefore, the engine and the electric control system thereof are protected, the hardware circuit is simple and effective, the cost can be reduced, the expense of the software is small, the reliability of the electronic fuel injection system is increased, and good effect can be achieved in the actual engineering application.