Rear brake light when depressed (hedlights on) brake lights go off . when brake depressed ( head lites off ) one lite works one doesn,t

Maybe a problem with multifunction switch?
Do the hazard lites work?
Does the high-mount brake lite work? The reason I asked, the high-mount brake lamp and lower brake lamps are wire differently. The lower brake lites are wiring through the turn signal switch.
bbbind.com has free wiring diagrams.

either a out of adjustment brake lite switch or a shorted brake lite switch..the mechanic may have hit the switch with his boot an caused damage

Since the high mounted brake light works you know that the brake light switch is working. Now you need to check the brake light bulbs in the rear tail light assemblies. The brake lights are separate from the tail light (parking or running lights). There are two screws that hold the rear light assemblies in place.

bad earth connection to the light unit

I WOULD START WITH THE LIGHT SWITCH IT SELF IF EVERY THING ELSE WORK THE LIGHT SWITCH TURNS THE TAIL LIGHTS

Look for a missing or poor ground connection on the rear stoplight lampsocket/s.

test lite the bulb, sounds like the bulb iz bad mebe,do u have trailer lites hooked up to tail lites? could be the wire harness. let me know.

If you have no dash lites< I would suggest checking either of the following as thse are the most common problems 1) chec your fuses 2) test the headlite switch, as for the brake lites I would again check the fuses and then move on to the brake lite switch and see if there is power going into the switch and coming out of the switch with the brake pedal depressed, if not it's the switch if there is power trace the wire back to the brake lites checking all connections in between for power. Finally test the lite pig tail ( socket ). Good luck and rember to rate all the solutions that you get on FixYa, thanx

Is there a switch on the left side of the dash that has a red lens and a wavy line across it? If so, you have a rear fog light switch and it has been activated, causing your brake lights to come on each time you turn your headlights on. Flip the switch and the rear lights should display only the parking lights with the headlights on.