The Last Problem to Tackle! Headlights Flickering and Dying

[Goose]

I am 99% done my build with one issue left, and I need the electrical experts to help me out. After completing everything and op checking it I thought I was done but after my drive today I noticed my headlights started flickering. I thought there was a loose ground somewhere but I briefly looked and didn't see one (though I might need to look harder depending on what yall recommend).

It's so weird, when I pull the headlight switch everything works as it should. Once I pull it all the way out to engage the headlights, they turn on. Using the highbeam switch they even turn on the high beams correctly and the indicator works as well. BUT, they only work for about 3 seconds...

Then they start to flicker and die and then come on for half a second then continue the trend of flickering and dying. This is the same with the car off and being static too, so this should eliminate a loose wire flickering when the car is shaking. The problem is worse when the high beams are on. With my car being done, I don't have the luxury of being able to easily access all of my wiring so I'm looking to see if anyone can point me in the right direction before I have to tear things apart and find the problem.

Thank you for any advice!

I have the Ron Francis wiring harness, the standard FFR lights, the 3 position/dimmer switch, on on switch for high and low beams, and the vintage gauges.

Side note (I noticed I blow the 15 amp fuse when I turn the headlight dimmer switch all the way counter clockwise, might be correlated, idk) I didn't think it was a major issue and I deal with it by rarely using the headlights but also knowing not to turn it all the way left, especially since it doesn't even dim the gauges.

[Jeff Kleiner]

The headlight switch incorporates a self resetting circuit breaker. Sounds like it's tripping and turning the lights off...then resetting and turning them back on...then tripping again...and so on. It may be a bad headlight switch OR it may be functioning as intended and tripping because you have a high resistance in the circuit somewhere due to a weak ground or poor power feed connections. If you replace the switch and the problem continues it'll be time to investigate the latter.

When you turn the headlight dimmer all the way counterclockwise you are activating the courtesy light function which is actually switching it to ground. Do you have a hot wire connected to the courtesy light terminal#5 and then back to the ground tab on the switch without a light in line? If so you're making a dead short.

Jeff

[Goose]

Thanks Jeff,

I just ordered a new switch and I'll swap that out to see if that's the problem. If not, I'll be back for some assistance haha.

And yes, I most likely have the wires for the courtesy lights like that since I didn't install the lights but followed the rest of the wiring schematic; when I swap the switch out I'll look to fix that hot wire.