Automobile insulation resistance detection circuit and insulation resistance detection method

The automobile insulation resistance detection circuit comprises a power supply module, a storage battery A, a power supply voltage detection sub-circuit, an automobile body electric leakage detection sub-circuit, a motor electric leakage detection sub-circuit, a motor working current detection sub-circuit and a motor coil detection sub-circuit, the power supply module, the storage battery A, the power supply voltage detection sub-circuit, the vehicle body electric leakage detection sub-circuit, the motor electric leakage detection sub-circuit, the motor working current detection sub-circuit and the motor coil detection sub-circuit are arranged in the element box and are electrically connected; the insulation resistance detection method of the automobile insulation resistance detection circuit comprises five steps. When the voltage is lower than normal, a vehicle owner can be prompted to charge; when an electric vehicle body leaks electricity, a motor shell is electrified, current data input into the motor is