Tattoovt, I'm in the same boat. Just finished a three year long rebuild and now the electrical is giving me hell.
When I took off the bed and reinstalled it, all seemed well. Until now. No gauge lights either, so I figured it was a the common issue of a ground that everyone seems to have.
They check out from what I can tell.
Fuses. All good.
Power to the panel is good. At times its a little lower than 12v at some of the fuses, kinda a concern but eh. Traced wires along the frame, seemed OK. Fixed some connections that previous owner did and were crusty. Still no dice.
Got the meter out and started testing things. No power to the rear sockets except the markers. Pulled it off the truck checked all the sockets, replaced some, fixed/added more grounds, and put all new bulbs in. Reinstalled; still no good.
Took apart the ground on the parking brake, cleaned the connection, didn't change. Finally checked the gauge cluster, turns out all the bulbs were just being funky from when I installed the new gauge bucket. So dash lights work and aren't the combined issue as some have had.
I've been working all day on it and it has to be something dumb. My hazards didn't work so I went and got a new relay and all of a sudden things started working again. Albeit, wrong, but a step in the right direction. So I know I'm getting power to things. Here's what I discovered:
All front lights work fine. Rears are the issue. Have all grounds alligator clipped to a solid ground on the rear harness.
Headlights off/Hazard relay out:
- brake and turns work as they should at full illumination and speed.
Headlights on/hazard relay out:
- slow/dim turn signal
- no tails/brake.
Hazard button pushed in with relay out and headlights off:
- No turn signal
- dim brake light
Hazard button in/relay out/headlights on:
- Tail lights on
- No brake lights. Tails off if brake pushed
- No turn signal
Relay in/lights off/Hazard button off:
- all fine
Relay in/lights on/Hazard button on:
- slow turn signal
- no tail lights or brake
Kinda long winded and jumbled, hopefully comes across as somewhat understandable. At the end of this I have some theories that maybe someone can confirm. Seems like the Hazard button could be a culprit, or the light switch maybe? Or, the relays don't like each other. The new relay is a "LED compatible" one. However, I have no LEDs installed. Or, I need two of the same so they get along.
I do have a wiring diagram that I've referenced here and there. As well as searched out online for other's solutions. So far none have been it. It's cold and wet so I've given up for the day and came inside to type this all up.
Thanks in advanced.
