[marks404]

32 ford, new build, ididit steering column added headlight relays, checked grounds on both along with turnsignals no change:drunk:

 

[vicrod]

Here's my guess.
The (2) wires that control the tailight and turnsignal bulb are reversed.
When the headlights are on the turnsignal filament is on. When you use the turn signal the tail light filament flashes but you can't see it because the bright filament is on.
When the headlights are off the flashing filament is visible.

vicrod