Evening all, got a 84 D-150, w/ 318, went to start it today and had nothing, threw charger on it, nothing, jumper cables, nothing, looked at battery cables and they are nice and clean, have power through the firewall with test light but under the dash, I cannot get the test light to "light up" on any of the fuses, wire harness' or anywhere. no lights, fan, wipers, absolutely nothing works, I did have a glimmer of hope when the dome light lit up, but as soon as I turned the key, all is dead again, that only happened once, can someone please advise if they ran into this before? talked with dad on the phone and I have all power to the right places under the hood, but once it goes through the firewall, it seams to go dead, all wires under dash look good, nothing burnt or corroded.....HELP please!!

I'd start by seperating the firewall bulkhead halves & cleaning the brass terminals. A small metal bristle brush for the male ones and a spare male one (new is NAPA 725147) for the female ones. Brush on Koppr coat (sp) if desired. Then with your meter on OHMs I'd see if you have continuity between the 2 main in/out wires at the bulkhead, the one in past the fusible link & the one out to the alt (black on that one I believe) & as you know it's always a good idea to unhook a batt cable before switching the meter to OHMs.

Dielectric grease is good stuff… pack that connector full of it after your done cleaning/testing and verifying everything it good again.

If it has an amp gauge.Pull the amp gauge.Ill almost guarantee its burnt,that and they had a problem with the ignition switch.Not the key but the switch and wire connector.Rocky