ENGINE DIES

I doubt its a PTO safety switch, as that wouldn't affect putting the hydro in gear.

Seat switch is the only one that affects both, pto and drive.

Ideally, you should probably replace the switch and wiring to original, but in an emergency, jumping the two wires together will get you going. Check and make sure the wires aren't broken under the rear fender deck or anything also, as a break anywhere will prevent the jumping at the plug from having any effect.

Basically, if the brake is on, and the PTO off, its considered safe to get off the machine. otherwise it would shut down everytime you got up. Must be in neutral also. If the brake isn't on, or the PTO is, the seat switch takes over and shuts the machine down.

I work on these things for a living, and run into similar problems all the time. Some seat switches on newer John Deere equipment can't be jumped also. Its wired different, and you must physically remove one of the wires from the plug, or cut one, instead of jump them together. (many customers calling after trying to jump them, with similar problems). If you look inside the plug on these, you see a small spring in there that contacts the 2 terminals when you unplug it. When its plugged in, the switch disconnects that spring, and the switch controls the connection of the two wires.

I think if you had a wiring diagram, you'd see that the ignition is wired through the seat, and parking brake and pto switches, and the cranking circuit only goes through the PTO and Brake switches.

This is the most common way I've seen machines wired. However, there are always variations and differences from manufacturer to manufacturer. John Deere though has done it this way with all of them, at least as far back as the 300 series.

I hope this explains it. I know its kind of long. Its much easier to show someone on a working tractor than explain it in words.

If not, I'll be glad to explain more if need be, or even send a copy of the wiring diagram for you to look at.

Thanks in advance, Peter