Turn signals, hazard flashers, and brakes.

[Brian VT]

Headlights/high beams work. Marker/running lights work.
No brake lights. Replaced the lower bulbs (the single-filament ones). I think those are the brake bulbs? One tested bad. New ones tested good. Replaced both for good measure.
Turn signals work, but seem a bit slow. No biggie. Would pass inspection.
No hazard lights. Replaced the flasher with a known good one. Still nothing.
Also, turn signals don't work when the hazards switch is pulled out.

Where to go next? Need brake lights and hazard flashers to finally get an inspection sticker on her after having it for a year.

 

[chillman88]

Did you replace the correct hazard flasher? There's two. 87 hazard flasher is on the passenger side behind the glove box.

You might just need to replace the turn signal switch. I THINK the hazards and the brake lights run through it but I'd have to look at a diagram to be sure.

 

[Brian VT]

Did you replace the correct hazard flasher? There's two. 87 hazard flasher is on the passenger side behind the glove box.

I found a second flasher on top of the fuse panel so I replaced it and didn't bother looking elsewhere.
Could there be a third flasher on the passenger side?

 

[chillman88]

I found a second flasher on top of the fuse panel so I replaced it and didn't bother looking elsewhere.
Could there be a third flasher on the passenger side?

That's odd... Maybe 87 was an oddball year? Both of my bricknose trucks (90 and 91) have it behind the glove box on the side above the passenger kick panel. I know it was on the back of the fuse box on the bullnose trucks.

 

[Nero]

Have you checked the fuses themselves? Brake lights should still work even with the turn/hazard relay missing.

 

[Brian VT]

I did check the brake lights fuse (I even used a multimeter as my eyes aren't quite as good as they used to be). And I think that was also the hazards fuse.

 

[Jesus Freak]

Your brake light bulbs should be double filliment, I'm pretty sure.

 

[Brian VT]

The top bulbs glow steady when I have the lights on and they flash when I turn the directionals on.
No lights come on when I push the brake pedal.
The bottom bulbs didn't light up for anything.
I took the bottom bulbs out and they were single filament. One was toast. I replaced them both with new single filament #1156. Still nothing down there.
I'm not sure which are the brake lights or the hazards.

 

[Jesus Freak]

Is it in the white lense? Those are your backup lights that come on for reverse, those are single filliment.

 

[Brian VT]

Doh. Maybe.
I've just been focusing on brake lights and hazard flashers as that's what the garage said I needed to fix.
So... brakes, parking, turns, and hazards are all the same bulbs then?
Bulbs are good. 2 flashers are good. Parking lights and directionals work. No brake lights and no hazard flashers. And directionals don't work when the hazard switch is pulled.

 

[IDIBRONCO]

I took the bottom bulbs out and they were single filament. One was toast. I replaced them both with new single filament #1156.

Is it in the white lense? Those are your backup lights that come on for reverse, those are single filliment.

For this and the above. Yes. Those are the backup lights. The bulbs are 1156 and they are single filament bulbs.

So... brakes, parking, turns, and hazards are all the same bulbs then?

Yes.

Bulbs are good. 2 flashers are good. Parking lights and directionals work. No brake lights and no hazard flashers.

Check the brake light switch on the brake pedal. Is it plugged in? If so, is it good? Do you have power to it and does that power go through when the pedal is pushed? If power doesn't go through the switch, then it's bad. One side is a constant hot. You can check your brake lights by putting power to the side (wire) that isn't a constant hot. Your brake lights should light up when you put power to that side.

And directionals don't work when the hazard switch is pulled.

That is most likely perfectly normal since the turn signals don't work when the hazards are being used. Remember, your hazards won't flash when you light up the brake lights even with the hazard switch pulled out. That is by design so that means that somehow, they are connected. Assuming that your brake light switch isn't working correctly, then it makes sense that the hazards may not work either.

 

[Brian VT]

Good stuff! Thank you.

 

[IDIBRONCO]

You're welcome. I may not be 100% correct on everything, but I'd start with the brake light switch anyway.

 

[ROCK HARVEY]

I’d take a look at your wiring under the truck as well. Previous owner of my truck did a real hack job adding/modifying the trailer hitch wiring, and it’s caused me problems with my taillights. I actually just bought a bunch of new wire to re-do the rear wiring harness.

 

[Brian VT]

So...it seems no power going to the brake switch. I stuck my multi-meter probes into the switch and got nothing.
And there does seem to be some wiring mods. down there. :-(

Also, I noticed another switch on the brake pedal. Actually more of a plunger. It seemed to have a hose connected to it as opposed to wires. Would this be to shut off the cruise control? Because I have to cancel the cruise control at the steering wheel. Brakes don't shut it off. I learned that the scary way. ;-)