John Deere D170 Won't Start?

My daughter borrowed my riding mower yesterday. New to riding mowers, she was mowing with the throttle at a low speed and of course, the lack of lift resulted in the bag chute filling up. She stopped the mower and Dad to the rescue. After explaining the need for a full throttle while mowing, I went to start the mower up and nothing. I checked the regular culprits (brake lock, mower engage lever, seat sensor). All were good. I checked the battery, cleaned the ignition harness and wires, cleaned the brake override harness, and still nothing. The hour meter works, lights work, and if I engage the mower lever while turning the ignition, it clicks. I did notice when I was brushing the ignition wire harness, the wire bristles created a quick "short" and the flywheel engaged for a split second. Not sure where to go from here?