Brake light wiring... need help!!!!!!!!!

[Rc 415]

Well, my right brake light does not work, and I can not figure out why, so I took a bunch of pictures in hopes of getting help, if you have any ideas please let me know!

[piecesparts]

Let's do this in a more dasterdly fashion---Start at the right brake light--First of all DOES THE TURN SIGNAL OR EMERGENCY SIGNAL FLASH? If it does, then the wire along the frame is complete. If not, then there is a break in the wire after the cab. If there is NO power at the brake light, then follow the wire back to the cab, checking to see if there is power at 2 foot intervals. If the turn signals work, then the problem is either in the directional signal switch assembly or in the wiring after it. You did npt say that the Left brake light did not work, so I assume that it is good.

According to my truck's factory shop manual the brake light switch has an Orange wire (#140) going to it that is a fused 12 volt feed. Coming out of the brake switch is a white wire (#17) going from the brake switch to the directional switch (Column switches) which appears to then tie into two wires a DARK green (#19) wire and a yellow (#18) wire that will feed out to the rear brake lights. Theses are the color of wires that you should be looking for at the cab wall and under the truck (along the frame) The numbers that I referenced are the numbers tha GM has llisted in their wiring diagrams for continuing reference from page to page.

[Rc 415]

The brake light, turn signal, and emergency flasher in the right light does not work, but the parking light, and upper filament in the main bulb does work. The left brake light completely works top to bottom.

[Rc 415]

oh and another piece of info is the dome light does not work, dont know if that matters but I'm throwing it out there, and I have already replaced every fuse.

[Srubydo1986]

thought llok were a person at one tim may have but a trailer bulg at right behind the bumber it may have gotten coroded and just gone bad. Being in virginia it happens alot to me.

[piecesparts]

Originally Posted by Rc 415

The brake light, turn signal, and emergency flasher in the right light does not work, but the parking light, and upper filament in the main bulb does work. The left brake light completely works top to bottom.

This info tells me that I would start looking in the wiring loom from the tail light assembly to the cab. The headlight circuit is complete due to your statement that the "Park" light is on, BUT the brake light, turn and Emergency is in one wire and that is broken somewhere and it could be on your frame or even just behind the bumper at the plug assembly that is referenced in the answer above.
Do you have a 12volt test light? That is one of those tools that has a ground wire and a very shrp pointed tip to allow you to penetrate wire insulation. This will allow you to search from the brake light going forward, until power is located and let you find the broken spot in the wire.

As for the dome light--Is the bulb good? This is different circuit completely but it is handled a different way. There is supposed to be 12 volt power to the bulb at all times, the dome light circuit is turned on and off by making up the ground circuit. This is done by either rotating the headlight switch knob all of the way to the left to the point where it is clicked into the place that completes the circuit, or the door pin switches make up the circuit (when the door is open. There is ONCE AGAIN an orange wire and a white wire. The orange is the 12 volt feed and the white is the ground. Check the orange at the light to see if it is powered up and then search back from there.

[Rc 415]

Originally Posted by piecesparts

According to my truck's factory shop manual the brake light switch has an Orange wire (#140) going to it that is a fused 12 volt feed. Coming out of the brake switch is a white wire (#17) going from the brake switch to the directional switch (Column switches) which appears to then tie into two wires a DARK green (#19) wire and a yellow (#18) wire that will feed out to the rear brake lights. Theses are the color of wires that you should be looking for at the cab wall and under the truck (along the frame) The numbers that I referenced are the numbers tha GM has llisted in their wiring diagrams for continuing reference from page to page.

Do you know if its the dark green or yellow wire that runs to the right brake light?

[Eyegore]

My son and i went through a similar problem3 weeks ago, we finally replaced the turn signal switch w/ harness in the column and the brake switch under the dash, seems a wire fried against his headers, did the harness and brake both in. His tail lights worked along with emergency lights but they were all very dim barely lighting the bulbs.

[Rc 415]

thanks, I narrowed it down to the turn signal switch harness and replaced it and it works now so all is good, some new tires, and I'll be on the road!

[Eyegore]

Rc where did you get your harness? We went to checker auto here (kragan) and the one they had would not fit, some rivet on the back held it up to high. So we finally went to the drealer who had the right one, little more $$$$ but well worth it.

[Rc 415]

Yup local dealer is where i get most of my parts including the turn signal switch