Ist thing I would do is lube them, Next chaeck to see if you have power coming to it., 3rd, take the cotterpin out of the push rod and see the motoris functioningl I had to replace a motor while in Florida once when mine went further south than we did. Good luck
If you open the door with the switch in the on position does the amber light on the step come on? If yes then you are getting power to the control box. If no then check the large red wire for power. If no power check your fuses and switches. If you have power the relay in the control box should click when you open and close the door. If it clicks check and see if power is getting to the motor. Test the small red wire going to the motor while opening and closing the door. ( the red and yellow wire should alternate hot depending on whether you are opening or closing the door) If you have power and the motor doesn't work then the motor has failed. Motors are about $150.00 so are Control boxes. The only other thing to test is the continuity of the magnetic switch.