tail light problems

Hey yall, came across a problem with the taillights and fog lights. For some reason when looking at my taillights, my turn signals work, my brake lights work, but when I turn my headlights on, my taillights fail to turn on. Is there a reason why everything works up until I turn my headlights on...

Hello, after months of this issue I thought I’d get other peoples opinions because I am stumped. On my 05 mustang gt, the brake lights and turn signals do not work. When I turn my night time running lights on my brake lights do turn on but when I press on the brake pedal they do not illuminate...

I have a 96 mustang auto v6 I swapped to a 98 mustang gt stick drivetrain. I can drive the car. I went on my first test drive and I noticed the rear lights do not work. Nor do the brake lights. Before you all say multi function switch, I swapped the multi function switch, I swapped the...