I have a 1967 f-100 pickup and my back blinkers work and so do my parking lights but my brake lights won't I've changed the switch and that didnt help I can't understand why they won't because I've heard that they run off of the same wires as the blinkers I've tried bridging it and that didnt work so I'm almost ready to just put it in the shop am have them fix it but that will be expensive any suggestions

that sounds like a earthing fault , check the wiring from the lights for signs of breaks etc, and trace earth back to chassis connection to ensure a good earth

Check the brake control switch situated just above the break pedal arm under the dashboard. Could be a wire loose or unplugged or the switch itself could be faulty

The dash lights and parking lights are powered thru the headlight switch.
Do you have voltage on those circuits in and out of the switch ?

check fuses for brake lights if fuse is good check for power to brake light switch with test light.

Park brake lights normally operate by a small plunger type switch the turns off when the level or pedal is placed in the off position. Over time the spring in the lever weakens and placing the lever in the off position no longer depresses the switch. The switch can sometimes be adjusted to make better contact, or the switch bracket can be bent so the lever and switch make proper contact.

Probably the blinker switch ..The brake light circuit runs through the blinker switch..Let somebody look and while you have the brakes applied move the switch around and see if the lights come on

check voltage to the sockets, if good check the grounds, if no voltage go to the switches and trace from there

Not even the third eye? then the fuse is blown or all the bulbs are out or the brake light switch on the break pedal is bad wire off or broken( it breaks right off the plug then crosses then blows the fuse as the loose broken wire hits the brake pedel arm. Test the break pedal switch first if the third eye doesesnt work either. no power with a test light the fuse is blown or the wire broke ( the wire goes straight to the switch from the fuse and doesnt go anywhere elese. the other wire if hot should light the lights. Most of these wont come out of park without this working as the wire also turns on the park release but some Fords the park release sticks released and Ford made em that way as they didnt like the brake to get out of park law. If the brake lights dont work maybe you ought not be able to get out of park anyway till its fixed. the switch is hot on both wires with the switch pused down and the lights dont still work go after the third eye first if the bulbs are bad change em before you do the rest of the work. on cars with yellow turn signals the brake lights all work on the same wire but red only use three wires, but you didnt say the turn signales didnt work if they work and they are red you r on the way to the turn signal switch as the brake switch powers the turn switch with power then it splites it fot the two lights and adifferent switch circuit for the front hooks them all together for hazard. yellow turns in the back or even separt bulbs can mean blown bulbs ther too its old enought for all the bulbs to fail and the runs still work.

I have a 98 Bucik Park Avenue. I recently had it painted and when the body man put the lights back in I began having problems with the brake lights and turn signal lights. Only one brake light lights up and only on signal light lightsup and they are on opposite sides. I have changed the bulbs (all) and I have tested the fuses(All).

probably needs a turn signal switch