no brake lights-need help

its a'84 LTD all the lights work exept the brake lights.they worked sometimes until yesterday now they dont work at all.all fuses and lights are good.when they did work they would come on if you barely hit the pedal but if you put it all the way to the floor they would go out.i dont work on to many fords so any help would be appreciated thanks

check the adjustment on the brake light switch on the pedal. if ajust is ok, check for power in and out of the switch when activated.