When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The brake lights & turn signals are one circuit, the lights that come on when the headlights are on are a different circuit. I believe they use a different bulb in the lens, too.
You do mean your tail lights.
Check the fuse, are your Dash lights working?
I believe they are both on the same fuse. Its a 20 amp fuse I think, I run a 25 Amp in my fuse block. But I also have running lights on the cab and the rear, and pull a cargo trailer with my 95 F-250.
Good Luck