Similar if not same issue here. I’ve been chasing this demon for a couple days now.
Battery is good at 14.7v
New ignition switch on top of the steering column. Multimeter shows good continuity and proper functions.
Fuses at fuse block are good.
My problem most likely hinges on the 12g purple...
Chasing wires under the dash of my ‘76 Jimmy. It’s a hack job from hel…heck! For some reason I have to use a toggle switch to power up the ignition switch and can’t find the culprit causing this work-a-round.