I recently replaced beat up wiring harness on my 58' apache with a wiring harness from a classic truck vendor. Since then, the Hi-beams will turn on just fine for about 10 seconds then flicker for a second or two then turn off completely. I don't remember trying the Hi-beams before the rewire as I had just purchased the truck from the previous owner. The re-wire was pretty basic, vendor provided a detailed diagram. I have replaced the dimmer switch and headlamp switch. Low beams function as they should. Anyone have an idea as to why it might be happening?
