Vehicle fault detection system

The utility model discloses a vehicle fault detection system which comprises a fault detection box, one side of one end of the fault detection box is provided with a first wiring jack, one end of a clamp spring is connected with an arc-shaped plate, and the inner wall of the arc-shaped plate is bonded with protective pad cotton. According to the utility model, a power supply system, a CAN acquisition circuit, a master control circuit, a storage circuit, an accelerometer monitoring circuit, an RS232 communication circuit, a 4G communication circuit, a GPS positioning circuit and the like are adopted in the fault detection box, and the power supply system comprises a main power supply chip and branch power supply chips. The main function of the main power supply chip is to convert an external input power supply into a usable power supply to supply power to internal devices of the fault detection box, transmit acquired vehicle information and states to a background for monitoring and data analysis, and perform p