Another turn signal problem.

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Cope

Cope

Fusing with fire
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Im still working on that dam 59 GMC pick up.

I got the front signals working by fixing the ground.
Now the problem is iat the rear.

When i press on the brake pedal the flasher stops flashing and all i have is break lights.

Some how the break lights are over riding the turn signals.

The rear lights are 2 wire.
I have a dedicated turn wire to each light that is new.
A wire that is running lights.
And the break light wire.

Some how i need to go 3 into 2 wires but no matter how i wire it i cant have turn signals and brake lights at the same time.

Any ideas would be a huge help.

I realise its not an A boddy but you folks are smartest folks around so i figured id ask here.

Thanks in advance.
 
Turn signal flasher interupt the power to the brake light on one side depending on the turn signal switch position.

Did you get a wiring diagram for your truck?
 
The wiring on this truck is not even close to original.
So the diagram for the truck would not be helpful.

The truck has a "modern" column and someone built the harness by hand.

I guess i could just look at a diagram for any 2 wire tail light?
 
==========================================
The rear lights are 2 wire.
I have a dedicated turn wire to each light that is new.
A wire that is running lights.
And the break light wire
==========================================

You lost me, please re-explain?

You should have this:

A ground at each rear lamp
A socket with an 1134/ 1157 bulb
A tail lamp wire branched off to one socket wire of both lamps
a left turn wire going to the left lamp
a right turn wire going to the right lamp

Brake lamps should be provided by the left and right turn wires, which are configured to stop both/left/ right inside the TS switch, depending on which direction, or neutral, of the switch position.
 
Some OLDER cars and trucks, made BEFORE factory turn signals Often used separate stop bulbs or even completely separate stop lamps, separate, that is, from the turn system

In that case, normally, one bulb or one lamp has a two filament bulb which is tail and stop

Then there would be a separate left and right bulb only for the turn. That should NOT be the case here, unless the system was hacked
 
I would wire it to match the column switch.
Also check to make sure hazard switch is off,if i recall some will cease flashing if hazards are on. an easy oversight.
 
Cope said:
The wiring on this truck is not even close to original.
So the diagram for the truck would not be helpful.

The truck has a "modern" column and someone built the harness by hand.

I guess i could just look at a diagram for any 2 wire tail light?
Click to expand...


Do you know what the column year/ brand is? That might be the key to the whole thing. As I indicated earlier, you normally want to make a 'truth table' of the TS wiring. You likely have a built in hazard switch? if it's a "modern" column. These normally have TWO flashers, and if the hazard switch is activated, the brake light switch WILL over ride the hazards or flashers
 
I have a universal switch that didnt intend for front signals, so im adding separate brake lights and running yellow signals all around.
 
67Dart273 said:
==========================================
The rear lights are 2 wire.
I have a dedicated turn wire to each light that is new.
A wire that is running lights.
And the break light wire
==========================================

You lost me, please re-explain?

You should have this:

A ground at each rear lamp
A socket with an 1134/ 1157 bulb
A tail lamp wire branched off to one socket wire of both lamps
a left turn wire going to the left lamp
a right turn wire going to the right lamp

Brake lamps should be provided by the left and right turn wires, which are configured to stop both/left/ right inside the TS switch, depending on which direction, or neutral, of the switch position.
Click to expand...


HUMMMM...

i think this is the key. Some how i have an extra wire.

I do not know the year of the column. I would guess, 1980s or 90s Chevy truck from the look of it.

I feel like in your post is the answer. I just have to figure out why i have an extra wire..
 
Lets try this.no luck. I think i have mid 80’s column wiring diagrams in the shop.
Theres some on the web, but it would really help to know the year.
What features on the stick if any,and style of column would help.
 
Last edited:
Typical system

brake off, turn signal centered
upload_2020-3-14_19-31-49.png


Brake on, turn signal centered
upload_2020-3-14_19-37-10.png



Brake off, Turn signal switch on for right signal

upload_2020-3-14_19-34-0.png


Brake on, Turn signal switch on for right signal

upload_2020-3-14_19-35-19.png


Added front turn signal to the switch
upload_2020-3-14_20-2-34.png






ignore the below image it is a dup and I cant get rid of it
upload_2020-3-14_19-32-47.png
 
Last edited:
Front wiring is different, brakes dont affect front signals.
 
Cope said:
HUMMMM...

i think this is the key. Some how i have an extra wire.

I do not know the year of the column. I would guess, 1980s or 90s Chevy truck from the look of it.

I feel like in your post is the answer. I just have to figure out why i have an extra wire..
Click to expand...

Bear in mind that some years in the 80s had separate brake lights. The tell tale amber rear lenses. So your column might be set up that way.
 
Talking to a buddy just now and he mentioned the same thing.

He said he has had issues when installing a modern column in old cars trucks.
The column is set up for a 3 wire and the cars trucks are not.
 
I BELIEVE you could get around that with a trailer towing "light converter" if you don't want to either change the column or add more lamps
 
Here's my plan for the morning.

Trace the wire coming out of the brake light switch.

That wire needs to go into the turn signal wires? Yes?

Hook the wire trace from my power probe to the wire at the rear of the truck and find the original turn signal wire.
Tie that wire into the brake light switch and done?
Right? Or no?
 
The way you worded this I'm going to say "no."

First once again it depends on the column and the type of switch. If the column is set up for integrated brake lights, the brake light switch output feeds into the turn signal switch

If the switch is NOT set up, and rather, uses separate stop only lamps, then the brake switch output must go to the rear, branch off, and feed to dedicated stop lamps

"Kinda" the first thing you need is to de-mystify that switch. Mopar, Ferd, and GM used "somewhat" standard wiring colors over the years. If you can start there---assuming you have a connector pigtail, that will be a start.

Worst case..........If you want to pull the switch and send it up here, I can figure it out for you
 
I can after work tomorrow.

The switch is inside the column. Not sure i want to pull the steering wheel off if i dont have to?
 
I would love nothing more than to send you the switch but i need this finished by Wednesday..
 
If your turn signal switch is designed for sperate turn signal bulb you could always add a bulb to the housing
 
This thing is a nightmare. Its a customers truck fresh out of 3 years in the paint shop.
Its all fresh paint so all the body grounds are gone. On top of that it turns out the harnes that was built in the truck basically was on fire at some point. All the wire in the truck is was melted. Then it all got painted,so i had a custom harnes that was built very poorly and burned up then paint all the wires body or chassis color and that is my guide....

This is one of those expensive lessons. I took this on as "fix some wiring issues."

Now im way over budget way past billable hours. Im jist trying to some how salvage this cluster and retain a client with out going bankrupt...

:)
 
Here's a HUGE THANK YOU to 67Dart and Dana!!

With your help i was able to get it all working.

I seriously can not thank you folks enough.

This has been such a burden on my mind and my pocket book. Its like a weight has been lifted

THANK YOU!!!

YOU FOLKS ARE THE BEST!!!
 
You helped me. I had to think the switch connections out, about 5 attempts later it all fell into place.

Now I have to add flasher cir!

What did you do / learn?
 
I cut out the entire harnes to the rear of the truck and built a new one using the diagrams you posted.

I was under the truck and wiggled the harness, i saw the harnes spark to the frame.
At that point i knew it all had to come out.

After cutting it out i unwrapped it and found (no lie) about 20 but connectors, two vampire crimps, some wire with exposed wire and a lot more melted wire....

Thank you so much!
 
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