Dc motor controller in use will encounter problems can't be started, the small make up to say, the cause of this problem. 1. May be the result of lack of power supply for power switch didn't together, before the fuse fusing, motor controller of main circuit and control circuit fuse fuse, so we need to fuse level began to once upon a time, slowly to the motor controller all the parts of the main circuit and control circuit conductor and the device for processing. 2. It is possible that the motor controller failure, because the brush wear serious problem such as, jam, spring pressure is not enough, so we need through the multimeter to check of resistance, looking for a reason and its repair. Above all, do you know about whether dc motor controller cannot be started.