# X320 PTO keeps shutting off



## Andrew Triplett (May 5, 2019)

I’m working on my granddads JD X320 s/n-M0X320A013476 bought in 2006-2007 has 895 hours. Has been to the JD dealer multiple times for for same problem. It will crank and run and cut grass but after 15-30 minutes the PTO will suddenly quit and blades stop turning. Trying to press and pull the PTO engrave switch will sometimes work and sometimes won’t after they stop that first time. Here is a list of what has been done to it or replaced from Newest to Oldest everything was done by the JD dealer the mower came from except I replaced the key switch yesterday - 


The electronic control unit and the seat safety switch (6-2018)
PTO switch (5-2018)
Battery, Starter, and Solenoid (6-2017)
PTO clutch (5-2017)
So far he’s spent $1000 or more at the dealer and no step closer to solving the same issue and has given up on the dealer so any ideas would be helpful (Note: I’m not a certified mechanic or do mechanic work for a living I just enjoy doing this on the side for family and friends as a hobby)


----------



## RC Wells (Dec 26, 2008)

Check the relay for the clutch, it really sounds as if it has failed if fumbling with the switch can make it work at times. Verify the relay has not failed, and that the lugs where it connects are clean.

There is also a diode, #18 in the following diagram: https://partscatalog.deere.com/jdrc/sidebyside/equipment/73796/referrer/navigation/pgId/2445577 The purpose is to keep the alternator from feeding back through the safety system. If that diode starts breaking down the clutch can randomly disengage.

If that does not find the problem, then lift the body off the lawn tractor, and trace the wiring from the seat safety switch to the ground speed control treadle, and the second lead to the control unit. Verify the ground speed switch is clean and functioning properly and the connectors from the seat all the way to the electronic control unit are clear of any corrosion or dirt. Do the same for the brake switch. Check all the grounds from the battery and wiring harness to be sure they are clean and making a good connection.


----------



## Andrew Triplett (May 5, 2019)

RC Wells said:


> Check the relay for the clutch, it really sounds as if it has failed if fumbling with the switch can make it work at times. Verify the relay has not failed, and that the lugs where it connects are clean.
> 
> There is also a diode, #18 in the following diagram: https://partscatalog.deere.com/jdrc/sidebyside/equipment/73796/referrer/navigation/pgId/2445577 The purpose is to keep the alternator from feeding back through the safety system. If that diode starts breaking down the clutch can randomly disengage.
> 
> If that does not find the problem, then lift the body off the lawn tractor, and trace the wiring from the seat safety switch to the ground speed control treadle, and the second lead to the control unit. Verify the ground speed switch is clean and functioning properly and the connectors from the seat all the way to the electronic control unit are clear of any corrosion or dirt. Do the same for the brake switch. Check all the grounds from the battery and wiring harness to be sure they are clean and making a good connection.


This mower the wiring harness is not quite like that one. What your showing on that break down is the fuse box on the mower and I have replaced all of those fuses and they are still fine no breaks or burnt ends. And I have taken the rear panel off and traced I’d say 85% of the wiring harness so far and all clean and good. Where is the ground speed? Sorry I’m learning as I go along on a lot.


----------



## RC Wells (Dec 26, 2008)

Speed pedal for hydrostatic. You will find a complex switch on the linkage that will switch the clutch out in the event the reverse pedal is pressed without using the override on the clutch switch. Switch cruds up and causes clutch to drop off line.


----------



## Andrew Triplett (May 5, 2019)

RC Wells said:


> Speed pedal for hydrostatic. You will find a complex switch on the linkage that will switch the clutch out in the event the reverse pedal is pressed without using the override on the clutch switch. Switch cruds up and causes clutch to drop off line.


How would I determine if it is the switch? Just buy a new switch and see? Or should I just wire it direct and skip the switch so it will back up and cut?


----------

