I recently bought an older 753 F Series Skid Steer. It has a problem with the interlock system being that sometimes the Interlock lights don't all light up (only the Power one at the bottom does) so nothing obviously works, and other times everything is on and no problem? It runs like a champion, but I obviously need to fix this issue. Over the years it looks like the Lap Bar Safety Switch has had the wires cut, and the seat switch has had something wedged under it so it is always on?? Sorry if this is all a bit vague, but I thought someone might have some ideas? I removed the main harness today that goes from the back of the cab, under the Hydraulic pump and back to the motor. It was all good with no damaged wiring at all.