Left side brake woes

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Jesus Chrysler

Forgiving Sins Against Mopar Since 1983
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So I'm getting solid 12v to the green wire at the kick panel connector when I have the left signal switch position closed. Back at the brake light I have really weak voltage (wont light the lamp, wires may be compromised) and if I make a jumper straight from the green wire at the kick panel connector to a lamp it will light up but no flasher. Right side works fine.

Car is a 67 barracuda FB.

Any thoughts?
 
Almost sounds like internal problem with the wire. Load light it and see.
 
I had similar issue once with '73 Dodge truck, tail light and brake light wiring had gotten crossed up.
 
I had similar issue once with '73 Dodge truck, tail light and brake light wiring had gotten crossed up.

Do you remember where they were crossed up?

Almost sounds like internal problem with the wire. Load light it and see.

I'm not familiar with a load light, but I did use jumpers right at the kick panel connector and got the lamp to light up, no flasher though.

I just tried energizing the green wire at the kick panel connector with the connector plugged in and it lit the right side brake lamp.
 
You would be much better off getting, and studying, a wiring diagram for your car, and using a test light/ohm meter to determine the circuit problem, rather than wasting time looking for an " internal wire" problem or "crossed up wires" !?? You have to know this kind of problem is not going to be fixed by the internet. Sorry, but just my opinion .
 
You would be much better off getting, and studying, a wiring diagram for your car, and using a test light/ohm meter to determine the circuit problem, rather than wasting time looking for an " internal wire" problem or "crossed up wires" !?? You have to know this kind of problem is not going to be fixed by the internet. Sorry, but just my opinion .

I have a wiring diagram for the barracuda but I dont have the turn signal switch diagram
 
Sounds like you have an issue in the turn signal switch in the column.
 
You should have flashing voltage if all is well.
 

Attachments

  • 67 Barracuda Factory WD REV 1.pdf
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First thing is ground. If both park/tail lamps are equal brightness, thats a good indicator of grounds and proper bulbs.
The same green wire is used for brake and turn. Also supplies the same element in the bulb. Both brake lamps should also be equal brightness.
If all about the green wire... If turn is bright and brake is not, or vise versa, the fault has to be in the signal switch contacts. The yellow wire at other rear lamp serves the same duty. So you could compare L&R operation in diagnosing if necessary. Left works fine , right don't, signal switch.
 
p. 8-71 has a functional diagram. Use that with the wiring diagram to make schematic you can follow.

maybe this will help you get started.
Power for the turn signals comes from the ACCESSORY terminal on the ignition switch. From there to the Flasher Module, then to the turn signal switch.
Power for the brake lamps comes from the Primary Distribution Point (a welded splice) which supplies the two fuses that are ALWAYS HOT. One wire from the Tail-stop-fuse go to the switch on the brake pedal. Its an 18 gage pink wire that also connects to the 4 way flasher module.
 
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I just tried energizing the green wire at the kick panel connector with the connector plugged in and it lit the right side brake lamp.
The dark green wire goes to the left rear stop-turn.
The light green wire in #1 cavity goes to the left front turn lamp
There's another light green wire that goes to the instrument cluster lamp (via the 4 way switch)
 
I posted it above . If you are looking for specific breakdown of the TS switch, the factory never did that.
 
Brake lamp power goes into turn signal switch on a white wire. Hold the brake pedal down and probe about with a test lamp. With signal switch centered you'll find the brake lamp current coming out on 2 wires , a green and a yellow. These are the rear lamp bright element wires. Work the signal switch to see each wire go off/ loose brake lamp current.
The signal switch moved left or right changes the power supplied on these wires from brake circuit to turn circuit. So now turn ignition switch on a check turn current out on same 2 wires.
 
Brake lamp power goes into turn signal switch on a white wire. Hold the brake pedal down and probe about with a test lamp. With signal switch centered you'll find the brake lamp current coming out on 2 wires , a green and a yellow. These are the rear lamp bright element wires. Work the signal switch to see each wire go off/ loose brake lamp current.
The signal switch moved left or right changes the power supplied on these wires from brake circuit to turn circuit. So now turn ignition switch on a check turn current out on same 2 wires.

Thanks for your input I will try this on my next go at it.

According to my diagram there are two white wires at my TS connector harness (which there are) and one goes to the flasher switch and the other to the brake light switch. A diagram of the flasher switch would also be helpful. Wiring diagrams are great but it kinda falls apart when you dont know how the switches are supposed to work.
 
Thanks for your input I will try this on my next go at it.

According to my diagram there are two white wires at my TS connector harness (which there are) and one goes to the flasher switch and the other to the brake light switch. A diagram of the flasher switch would also be helpful. Wiring diagrams are great but it kinda falls apart when you dont know how the switches are supposed to work.
Power comes through the brake switch. The brake switch is connected to a fuse and is always hot.
 
Thanks for your input I will try this on my next go at it.

According to my diagram there are two white wires at my TS connector harness (which there are) and one goes to the flasher switch and the other to the brake light switch. A diagram of the flasher switch would also be helpful. Wiring diagrams are great but it kinda falls apart when you dont know how the switches are supposed to work.
With the links in above post #20 you should have more than enough info to diagnose it. good luck
 
Back at the brake light I have really weak voltage (wont light the lamp, wires may be compromised)

Have you recently done work where you removed and reinstalled the sill plate or anything else on that side?

If yes, I would double check to see if you haven't pinched that particular wire with something and partially grounded it.
 
First sentence of post number 10.
Grounds are horrible in these old girls, and I use a separate grounded wire to test this.
Hook it to your bumper or wherever you can get a good ground, then touch the base of the offending light with the other end of your wire while the light should be on.

If it lights when you touch the bulb base you found the problem.
Touch the actual base metal of the bulb, and not the socket because the socket can loose it's connection to the lens housing.
I would do this before I went through a bunch of possible pointless diagram hunting.
 
First sentence of post number 10.
Grounds are horrible in these old girls, and I use a separate grounded wire to test this.
Hook it to your bumper or wherever you can get a good ground, then touch the base of the offending light with the other end of your wire while the light should be on.

If it lights when you touch the bulb base you found the problem.
Touch the actual base metal of the bulb, and not the socket because the socket can loose it's connection to the lens housing.
I would do this before I went through a bunch of possible pointless diagram hunting.

I used 3 jumper wires with alligator clips from the light socket to the trunk latch. I've also got tail lights working properly without the additional grounds.

The light socket has definitely seen better days, though. Does anyone have a part # to reference for correct replacements?
 
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