The seat switch and the brake switch work together to cut off the engine if you should happen to fall off, but allow the engine to run if the brake is on so you can open a gate or move an obstacle on the lawn.
The PTO switch and the seat switch also work together and shut off if the blades are turned on and you are not in the seat .
These safety circuits are GROUND circuits so if a tire is pinched or abraded or in any way touching the mower, the engine shuts down.
