Of course it is a Saturday, I am pulling a manure wagon in field and all of a sudden the corner post warning comes up and says stop pto. Did a quick google check , I checked the hyd oil , it was fine, alternator  is at 14.1 volts , went to shop and cleaned around the sensor on top and bottom ,wire looked good, changed hyd filter , even thought it didn’t have many hours on filter, I am going to,call dealer on Monday but just in case someone might know what I could do to Get it running .  Thanks in advance guys for any help.