how to repair a proform treadmill?

Have a Proform 985 treadmill. It will not run. Was working until recently. The power turns on, and the console lights up. You can set the speed, but the mill doesn't turn. The elevation control functions normally. Lifting the hood, the lights indicate that the signal is being received from the console, and that it is transmitting it to the motor. However, the motor does not turn. Any ideas?