"Electric Car Brushless Motor" motor running inside a mechanical collision or mechanical noise: Whether high-speed or low-speed electrical motor, load operation should not be a mechanical collision or discontinuous irregular mechanical noise. Different forms of motor may use different methods for maintenance. Vehicle mileage is shortened, motor weakness: the car continues the course is short and the motor weakness (commonly known as motor boring) the reason is more complex. But when we exclude the above four motor failure, in general, the vehicle continues the course of a short fault is not caused by the motor, which decay and battery capacity, Chargers dissatisfied electrical controller parameter drift (PWM signal does not reach 100%) and so on.