I have the same game. Been working on it off and on for six months. The first thing to do is check all fuses. Then check all switches. Check them closely, a switch may look open, but double check. Clean all stepper units. There a lot of information on this site about cleaning. Reading the schematic will get easier as you go along, break the schematic down to smaller parts. Example if a relay is not working look for that relay on the schematic, then back track, what causes it to activate. Take your time don’t give up.
Kickout