Everything on this machine works execpt spindle enable. I know that spindle forward or reverse switch must be activated at same timeas spindle enable button. I can ground the contactor coil & spindle will run. the enable button goes tocircuit boards dps,fmdc2,salf and on to contactor. What I don't how to do is check signal path or know what to look for. Somehow not getting ground to contactor. Hope some can help. thanks so much. The way oil switch checks out OK & overload is not triped, or defective Minnesota hd10

The 2 most common reasons that a spindle will not start are:
Way oil level too low or bad float switch.
The overload for the spindle is tripped.

George