Truck won't start12 F-350 6.2 300,000. Have been chasing down electrical Gremlins for the past 4 days on this truck didn't get the yellow light of Park reverse neutral Drive got that fixed. Then it started then it did it again to where it wouldn't start found some more chafed wires by the BCM fixed most of them. But now I have no ground going to the starter relay I have power at the starter relay but no ground I can jump the starter and it'll crank so the starter is working. I'm not getting negative to the starter relay I can hear the fuel pump run when I open the key and the the engine cycle the throttle body when I open the key but I don't I don't get it to crank or start last thing I messed with was the BCM so I am guessing some wire broke or I have to look for more broken wires in that area but if anybody has seen this problem before I will take any suggestion.
edit. truck isnt mine, im gonna suggest time for the junk yard and time for a chevy. truck is old not worth even putting any money in it im trying to fix it for my dad for free will tell him to put anything he was going to give me or a mechanic towards a car or another truck.