Looking at it again this morning, I was going to remove the solenoid to bench test it and thought the ground terminal pulled off a little too easy. I squeezed/deformed the female harness connector a little so it would push on the solenoid tab a little tighter, and the mower started. I didn't...
Model 13B9A1CS010 ser#1D108H40176 115hours Won't turn over. When starter button is pressed, LCD shows voltage for ≈2 seconds, then a barely audible relay click in the keyswitch and hum (fuel pump?) and showing hour meter, then nothing changes until timeout. No (louder) click from starter...
My lawn tractor has done that a couple times. I start taking apart the plastic molex connectors and flushing with electrical cleaner/lube, and after each one cleaned, try the starter. There's probably 6 of them on the machine and mostly are about the safety lockouts.