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Old 06-06-2021, 10:03 AM   #26
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Re: Wiring turn signal question, purple wires

Aftermarket ign switch pigtial.
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Old 06-06-2021, 10:08 AM   #27
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Re: Wiring turn signal question, purple wires

Well, it wont allow to me upload pics of the wiring schematic. I was simply trying to show the difference in the wiring schematic, and when you are able to zoom in and see small differences (which I was not able to do until I got a new laptop...I am now able to zoom in and I had some wires I THINK in wrong locations)
However, that would not explain why one day everything worked and now I am having problems. Either way, I am going to go test my theory and will report back.
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Old 06-06-2021, 10:19 AM   #28
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Re: Wiring turn signal question, purple wires

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The picture got rotated. Not sure how to fix it. BUt my pen is pointing to the light switch. I am pointing to an outlet where it says a brown wire should go in there. That brown wire leads to the 2 dark blue front turn signal lamps.
However, on my old factory light switch, AND my new light switch there is NO wires in that location on the switches. Does anyone know if I can take that wire (from the 2 dark blue to one single brown, to the other locations on my light switch?
If not, where does the brown wire go? Again, it is 2 dark blue wires from front turn signal lamps, they become ONE brown wire at the firewall, and then that wire is supposed to go into light switch, but according to schematic, it goes to different location then what I have.
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Old 06-06-2021, 11:34 AM   #29
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Re: Wiring turn signal question, purple wires

The dark green wire coming out of headlight switch. Goes to fuse box. Is it hot all the time, or only when key turned in run position?

With lights off, should it be grounded?
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Old 06-06-2021, 11:41 AM   #30
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Re: Wiring turn signal question, purple wires

flip for ya.

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.
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Old 06-06-2021, 12:25 PM   #31
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Re: Wiring turn signal question, purple wires

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Originally Posted by Getter-Done View Post
flip for ya.

Attachment 2106479










.


Thank you.
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Old 06-06-2021, 01:02 PM   #32
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Re: Wiring turn signal question, purple wires

OK, making progress but still similar issues.

I THINK I have a turn signal switch problem.


I hope yall can keep up. Sorry about this, but here we go:


With lights OFF, if step on brake pedal, the FRONT turn signal lamps illuminate (as does rear brake lights.) The front lamps are normal in brightness when applying brake pedal (I know obviously they should not light up when hitting brake pedal)

With lights ON, the front turn signal lamps are BRIGHT like the turn signal bulbs is illuminated, but they are NOT blinking. The rear turn signals work just fine at this time.

SO, I checked power at the "U" shaped connector under steering column, and when I hit the brake pedal, the turn signal wires power up (the blue and light blue wires)
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Old 06-06-2021, 01:19 PM   #33
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Re: Wiring turn signal question, purple wires

Post a photo of the wires connected to your U shaped connector.
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Old 06-06-2021, 01:25 PM   #34
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Re: Wiring turn signal question, purple wires

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Post a photo of the wires connected to your U shaped connector.


Give me a few minutes and I will.


Good thing Im pig headed as Im not accepting defeat. LOL

Just when I THINK I have it figured out, I fix one thing only for a different problem to pop up.
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Old 06-06-2021, 01:26 PM   #35
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Re: Wiring turn signal question, purple wires

U shaped connector under steering column.

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Old 06-06-2021, 01:31 PM   #36
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Re: Wiring turn signal question, purple wires

Current situation:


Turn signals work. Brake lights work. Taillights work. Head lights work.
Left turn signal works with brakes on (right side gets bright) and left tuen stays blinking.

HOWEVER, when turn right turn signal on with brakes, my left rear brake light does not get bright.
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Old 06-06-2021, 01:41 PM   #37
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Re: Wiring turn signal question, purple wires

Your U wires are in the same order as in this spare harness I have. So you were able to fix the issue with the front turn signals?
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Old 06-06-2021, 02:46 PM   #38
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Re: Wiring turn signal question, purple wires

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Originally Posted by pjmoreland View Post
Your U wires are in the same order as in this spare harness I have. So you were able to fix the issue with the front turn signals?

Yes, front turn signals work in current situation, but they do NOT illuminate when turn parking light on or head lights.

But they no longer get BRIGHT when turn lights on, and they do not come on when hit brake pedal.


So, front turn signal lamps do NOT come on when lights are turned on and everything else works except:

The left rear brake light does not light up when I have the right turn signal on. Brake light works when have lights on, or lights off (as does right side).
left rear brake light ONLY does not work when have brake pedal pushed in and right turn signal on.
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Old 06-06-2021, 03:20 PM   #39
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Re: Wiring turn signal question, purple wires

Whenever I hear about problems where the turn signals work, but the brake lights don't in certain scenarios, I suspect the turn signal switch, since it reroutes the brake signals depending on the position of the turn signal switch. I had a problem where a gummed up turn signal switch made my brake lights not work at all due to varnish on the contacts. Did you try moving the turn signal lever around a little bit to see of your left brake light will come on when the right turn signal is on?
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Old 06-06-2021, 03:44 PM   #40
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Re: Wiring turn signal question, purple wires

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Whenever I hear about problems where the turn signals work, but the brake lights don't in certain scenarios, I suspect the turn signal switch, since it reroutes the brake signals depending on the position of the turn signal switch. I had a problem where a gummed up turn signal switch made my brake lights not work at all due to varnish on the contacts. Did you try moving the turn signal lever around a little bit to see of your left brake light will come on when the right turn signal is on?
Yes sir I did that, no dice.

But I am thinking of the same thing, turn signal switch.

But, I am still at it.

I would really love it if someone could chime in about the wiring for the "U" shaped connector under the steering column.
Thats really the only wiring I do not have a clear grasp of on what goes where.
The head light switch, only question I have there is, the green wire....with lights and everything turned off, it is a clear ground (my test light beeps and gives me a green light showing it is grounded). When I turn head lights on, it goes hot. But, where EXACTLY does the green wire from head light switch go, AND is it grounded with lights/key off, or should be hot all times, or?????
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Old 06-06-2021, 03:45 PM   #41
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Re: Wiring turn signal question, purple wires

That is green wire I am referring to. I know it goes to fuse box. But with lights off and key off, it is grounded. When turn key on, it goes hot (or if turn lights on). Is it hot all times, or key on hot?


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Old 06-06-2021, 04:25 PM   #42
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Re: Wiring turn signal question, purple wires

This came with an aftermarket turn signal switch I had in my truck for a few months. It has the wire functions listed.
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Old 06-06-2021, 04:53 PM   #43
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Re: Wiring turn signal question, purple wires

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This came with an aftermarket turn signal switch I had in my truck for a few months. It has the wire functions listed.


Awesome.
I will take a look and see if these match up.

I also went ahead and ordered a new turn signal switch.

I'll post back later once I match it up.
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Old 06-06-2021, 04:55 PM   #44
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Re: Wiring turn signal question, purple wires

You might be able to just clean the contacts in your current turn signal switch
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Old 06-06-2021, 06:25 PM   #45
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Re: Wiring turn signal question, purple wires

This might help you if you don't have the link yet.

POST- #1 and #2 there is a link to expand the size and let you zoom in. Looks like the green goes to the fuse panel.


In my truck I have found that auto and stick shift trucks have some other color wires here and there but follow the paths and you should come up with where they go and what they do.



http://67-72chevytrucks.com/vboard/s...d.php?t=185856
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Old 06-06-2021, 07:28 PM   #46
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Re: Wiring turn signal question, purple wires

The dark green wire at the head light switch (cir #44 ) should be the + feed for the dash light fuse ( gray # 8 wire ). Should only be hot with the head light switch on. Turn signal connector under the dash. Dk blue#15A goes thru the bulk head connector to a splice then on to the right front park turn signal and the right side marker. ( turns into a black wire at the splice ) Dk Blue #15B goes to the cluster plug. Lt Blue #14A goes thru the bulk head connector to a splice then on to the left front park turn signal and the left front side marker. Also turns into a black at this splice ) Lt Blue # 14B goes to the cluster plug.
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Old 06-06-2021, 07:48 PM   #47
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Re: Wiring turn signal question, purple wires

The ign switch pigtail in your truck doesn't have the Dk green wire for the temp light cir. bulb check. I am guessing you have a gauge. The aftermarket pigtail does.
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Old 06-06-2021, 08:10 PM   #48
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Re: Wiring turn signal question, purple wires

Quote:
Originally Posted by pjmoreland View Post
You might be able to just clean the contacts in your current turn signal switch

Roger that.
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Old 06-06-2021, 08:11 PM   #49
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Re: Wiring turn signal question, purple wires

Quote:
Originally Posted by Hunter757 View Post
This might help you if you don't have the link yet.

POST- #1 and #2 there is a link to expand the size and let you zoom in. Looks like the green goes to the fuse panel.


In my truck I have found that auto and stick shift trucks have some other color wires here and there but follow the paths and you should come up with where they go and what they do.



http://67-72chevytrucks.com/vboard/s...d.php?t=185856
Yes sir, Im finally on a computer that zooms in. LOL!

What I was curious about it, is hot all the time? Or only when key or headlight switch on?
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Old 06-06-2021, 08:14 PM   #50
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Re: Wiring turn signal question, purple wires

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Originally Posted by BigBird05 View Post
The dark green wire at the head light switch (cir #44 ) should be the + feed for the dash light fuse ( gray # 8 wire ). Should only be hot with the head light switch on. .

Do you know if it is grounded with headlights off? Right now, I have it going to fuse box but with everything off, it is grounded. As soon as I turn headlight on, it goes hot. I just know that some times, if something is grounded, then it goes hot, it reacts differently then if it is NOT grounded, then goes hot.

I am curious to know if it is supposed to be grounded when everything is off? Because if its NOT supposed to be grounded, that might be my problem.
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