first thing to do is check the power going to the motor- disconnect the plug to the motor-turn on the ing. switch to on.

check both wires- one should have power-"close" side.
the other should be dead.

now turn on the lights and the ing. switch on- they should now be reversed- the one that was off is now power for the "open" side.

if this checks out- the small park contact in the motor is open- not allowing the power to go to the motor to turn it closed-
a normal operation is the contact is closed- power goes thur it to the motors windings- when the doors are closed- the contact inside will open and turn the power off to the motor.
same as the reverse to open the doors.

hope this helps

John Mac