model 1694455 zero turn shuts off

Driving across my driveway and all of a sudden it shuts off. Disengage the drive handles and put on the brake and it starts fine and runs. As soon as I let off the brake or engage the drive handles it shuts off. Would think it has to be a ground issue or something further up the safety switch circuit as both the brake and drive handle safety switches will shut it off. Looking for anything to try and chase this down.

If it happens with either the lap bars or the parking brke then the seat switch is duff or the kill relay ( which is connected to the seat switch ) is duff.