93 cummins help

[SSDiesel512]

I have friend that has a 93 cummins it has no lights interior or exterior the radio will not come on when you turn the key on but the truck will start but when you turn the key off it will not turn off.I have traced wires and still no sign of what is doing that any help would be great thanks.

 

[Bogie]

Start with the fuse able links on the drivers side inner fender, in between the batt and the main harness.