1997 Ford Light Duty F-250 Problem: Passenger rear brake light / signal light Brake light is intermittent. Signal works most of the time. Emer. flasher is intermittent. Center & left side work fine. I changed the lamp, checked and cleaned the socket. It works for a while then no brake light but turn signal works. While working on it over several days everything would work then no brake Maybe no flasher. Someone told me last month it was out but when I checked everything seemed fine??

I have to think the problem is inside the turn signal switch, a poor internal connection. You know the brake signal first goes through the turn switch before it goes to the bulbs. That is why the brake lights and rear turn signal lights share the same filament in the bulb, and the same wire going to those lights. The only difference is the turning side light is affected by the turn signal flasher, causing blinking, while the other side- the non turning side-does not go through the flasher relay, but straight to the bulb from the turn signal switch. Change your turn signal switch and I believe you will solve the problem. Let me know, okay?

The brake warning light is for the hydraulic system.
It could be low on fluid or several other things. There may also be a warning light for a dead brake or tail light.

THE TAIL/MARKER LIGHTS, GO FROM THE HEADLIGHT SWITCH TO THE REAR FOR THE TAIL LIGHTS & TO THE FRONT FOR PARKING OR RUNNING LIGHTS. ALL THOSE LIGHTS ARE ON THE SAME CIRCUIT, { BROWN WIRE } THE BRAKE & TURN SIGNAL WIRES GO FROM THE STOP LIGHT SWITCH & FROM THE TURN SIGNAL/HAZARD SWITCH. NO RELAY IN THE TAIL/PARK CIRCUIT. CHECK THE FUSES WITH A GOOD FUSE TESTER.

The turn signal/brake light wire goes to the turn signal mechanism in the steering column. It does this so your brake light and turn signals work at the same time. For example you put your foot on the brake and the left brake light will come on but allow the right turn signal to flash. Try you four way flashers and see what happens. Also be wary of the socket the bulb fits into. Double check for voltage with a test light at the wire coming in from the back. Check that the socket is getting a good ground. You can run a ground wire to a clean area of metal from the socket if you have to.
Let me know. Lee

If you have already check fuses, and brake light's still don't work, it's going to be your turn signal switch, the brake light circit runs thought the brake light switch, if your car has a middle top brake light in back of rear window, most of the time that one will still work, and the turn signal will also work, but not the rear ones brake light's, when turn signal switch is bad, hope this was very helpful.

Most likely, open the trunk/rear hatch, look near where the light is, you might have to remove some covering and then you should see some screws.

you replaced the bulb with the wrong one i.e. a two filament bulb with a one filament bulb

Check the ground on the passenger side rear lights, it's likely bad. As for the hazards, sounds like a bad flasher or fuse.

Had the exact problem on my 98 ranger 2wd reg cab stepside with the 2.5l 4 banger. Anytime I pressed the brake my passenger side turn signal would light up solid on the dash and the lights outside. I pulled both rear lights and both headlights and turn signals to check for corrosion/loose wires. Nothing. I checked and cleaned all my grounds and fuses. Nothing. Not until I followed my rear taillights wire harness did I find the problem. The two taillights are connected to each other via wire harness. My truck had the harness split with an adapter for trailer brakes. This harness was the problem. It is located under the rear bumper by the spare tire. Simply disconnect two harness plugs going into each side and remove it. Then connect the two plugs to each other. Problem solved.

It sounds like a wiring fault - an earthing problem. Have a look around the lights/inside the lights themselves.. rear and front lights, brake lights, etc ...check the wires for corrosion/splitting. In particular check any black earth leads where they attach to an earthing point.