Some common garage door motor repairs include replacing the main gear and replacing the control board. Both repairs are relatively simple, and parts cost between $20 and $80, as of 2016.
If there is power at the outlet, but lights do not illuminate and the motor does not start with the push of the button, a lightening strike could have affected the circuit board. Replacement with a new one takes about 10 minutes. If the unit makes grinding sounds but the door does not open and the carriage does not move, replace the plastic main gear drive. A broken main gear is the most common reason most units fail.