I've seen the 6 volt power set up , and it's as you describe , connected to one battery, I'd look first at the battery bay for a wire hanging loose. ( wire end corroded off) If the wire is hooked up then follow it looking for a main in-line fuse on it's route to the fuse panel.
__________________
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.
|