It goes partway down reverses direction and goes back up again.
Garage door closes then reopens.
If your garage door won t open or close the problem could be a bent track a broken torsion spring or a bad capacitor int he motor housing.
If you re craftsman chamberlain etc garage door opener is closing and then opening up its likely a common problem related to the stop limit mechanism.
Your garage door is programmed to travel a certain distance before it closes.
This is almost always the result of a dirty or obstructed safety feature.
If it closes only partway the safety sensors are usually responsible clean the lenses or realign them and make sure there are no obstacles blocking the beam.