The original post is pretty old and the problem has been solved. That said, I had a similar problem. Turned out the wires on the PTO unit were broken right where they enter the main PTO housing. They looked alright physically, but the copper wires inside the insulation were broken. What caused this was inadvertently turning the PTO while removing the drive pulleys, gotta be careful not to let that happen when the PTO stop is removed, as when taking the deck off.
I was able to peel back the insulation and solder the wires, all is now well again. It taught me a lesson on being very careful not to let the PTO housing turn when removing the deck or blade drive belt (and the PTO locking bar is removed). It doesn't take much to break those wires, and if they do break it happens very close to the drive housing and not easy to repair