What series is your toolcat? My symptoms were the same as yours, not much I know. Just kept blowing a fuse when turn key on in park, And obviously you can't start it in F/R Is 4 wheel steer engaged? If so, disengage and try again. I say this because mine was related to a bad solenoid on the the same circuit. This will be a wild guess on yours obviously. You will need a schematic of that wiring, whatever else is on that circuit is where the problem is. Naked wire, bad solenoid , etc IMO. Get a good meter if you don't have one.