The servo driver is a controller used to control the servo motor. Its function is similar to the frequency converter. It is used for ordinary AC motors. It is a part of the servo system and is mainly used in high-precision positioning systems. Generally, the servo motor is controlled by three methods of position, speed and torque to achieve high-precision positioning of the transmission system. In order to ensure the normal operation of the equipment, it has become a very important task to judge the fault in time and deal with it in time. Here we will introduce the analysis and troubleshooting of the AC servo motor driver.