specequip;
Look closely, does the truck's directional contact trip once (open and remain open) or trip twice (open-close and reopen). The logic card would be the last item to question. The tripping of the contactors, the hum, and the ability to reset raises some doubt that you have a bad program card. Once we know what kind of tripping action you are getting we can define if you have a problem in the charge up circuit or if you have a voltage split problem.