I have a John Deere Sabre 2046 lawn tractor. Every time I release the brake the engine dies. Thinking it may be the seat switch, I disconnected the seat switch connector and put a jumper wire across it but it didn't make any difference.

Does anyone have any idea what switch could be causing the problem here? If not, does anyone have a wiring diagram for this?

Thanks,
Dan

Sounds like seat switch to me.
Check the plug going to the seat switch , if it has a little spot in the middle of it that pushes in you can't jump it.
Plug the switch in and put a jumper on the back off the plug.
Luck

Yes, I already unplugged the seat switch wire and put a jumper across the two wires but that didn't make any difference.

Read what I said some switches can't be jumped by doing that.