brake light issues

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...