I have a John deere gt 235. The pto to the mower quit today. This model has a pto switch that you pull out to keep the mower running when backing up. I believe the switch is the problem. What do you think?

Maybe switch not adjusted properly. Would disconnect battery and ohm out the switch.

How To Replace John Deere PTO Clutch

check your fluid level for the hydraulics and look and check that the pto rods are connected and adjusted correctly

These John Deere Garden Tractors have a RIO (Reverse Implement Option) on the PTO. If your PTO is engaged and you back up, the PTO will automatically stop. To reset it, depress your PTO engagement switch to the OFF position. Take your foot off the reverse pedal. Pull up on the PTO engagement switch. The PTO should restart. To use the RIO feature, pull up on the PTO switch for a second or two just before you step on the reverse hydrostatic pedal. The yellow RIO indicator light should come on your dashboard and you can now back up with the PTO still running. Works great for snow blowing when I don't want to keep resetting my electric PTO clutch to keep restarting my snow blower.

If your PTO will not restart, you may have a PTO switch starting to fail, or a likely logic problem in your electric PTO control module, or one of your forward/reverse indicator switches, which is linked to your PTO control module along with the overtemp circuit, is stuck/faulty.

Bad electric pto and also there is a fuse up by the dash underhood if thats blown it will not start from key.

check the safety switches

pto is going bad

One of two possible causes;either the PTO switch is defective or the switch for the reverse peddle is out of adjustment .The only other thing i have seen cause the PTO to shut down is a lack of battery power due to the machine not charging.

sounds like the seat switch is bad

sounds like safety switch