I just got a 90 f150 and the brake lights didnt work i replaced the switch and that didnt fis it. i then replaced the fuse and they worked for a while then quit. my four way flashers do not work, my turn signals do. i checkd the fuse and it is good. i then ran power to one side of the wires on the brake switch and the brake ligts came on, i ran power on the other side and no brake lights when i push the pedal but the 4 way flashers started working.