Wire ID

[skolman91]

Have 3 wires i need ID'd if someone could be so kind, im sure their pretty easy ones.
The pink, and 2 red wires in the pics on the left side of main firewall harness connector. One red wire comes from the alt, other red wire comes from the power block on firewall, and the pink one was cut so i have no clue. Im guessing the obvious the red wires go to fuse panels inside but specific locations would be great so i can mark them.
The thick purple wire is the starter, and the black the interior ground i know that.
Bonus points if you can tell me what the smaller purple and grey wires seen in the bottom of both pics that have butt connectors on them that come out of the rear harness firewall connector go to, i havent had a chance to trace them yet but i think one is the fuel sender..?
thanks

 

[Don W.]

Re: Wire ID

This all may depend on whither you have a Sy or Ty. I only have the Sy books.

First pic doesn't show. Both reds come from the alt. One direct, one via the junction block on the firewall. The 'direct" one ends up on the two Bat terms on the ign sw.

For the other I'll have to look in my big book.

I believe the smaller ppl and gry wires are to the rear (lights, whatever) and I believe this also depends on whither you have a Sy or a Ty.

You might wait for Dave to chime in, he, somehow, has this stuff in his head. Or he cheats.:rotf:

BTW, that term block -can- be taken apart and reduced to its 3 different sections. Kinda a Chinese puzzle but it can be done without breaking anything.

 

[skolman91]

Re: Wire ID

You are correct they both come from the alt, just one via the junction block.
Its for a sy btw.
Im guessing One is ign switch, one fuse block, and the pink one no idea..

 

[Don W.]

Re: Wire ID

According to my book the pink is key on to the Coil. Does this thing run?

At the bottom are you talking about the gry wire with the splice?

(PS I won't be able to answer until maybe 8:00pm local.)

 

[skolman91]

Re: Wire ID

Okay that makes a little more sense now about the pink wire if its the coil + wire.
Nope not running, no engine in it..lol Just starting to clean up wires and fix all of the mess im in no rush..

Yes the grey and purple wires with the splice connectors, they are in the rear harness that runs along the frame rail to the back.

So the red direct off of the alt goes to the ign switch correct?

 

[Don W.]

Re: Wire ID

Someone can audit this but red (the one next to the orn wire) goes to the ign and becomes stoplight feed.
The other red = Lights then horn, tail, ECM-B

The small cluster.
Marker = Brn
Haz&Turn LH=yel RH= dk grn (This is also your turn sigs.)
Backup = lt grn

EDIT:
pnk fuel ga
tan fuel pump

Like Regan said "Trust but verify."

HTH

 

[skolman91]

Re: Wire ID

Thanks don i appreciate it

 

[Don W.]

Re: Wire ID

No prob. I had that connector completely apart last winter. Everything you want is in the two wiring diagrams. The standard one and the Sy supplement. But even with our "little" pickups there are a lot of wires. And much of it changes depending on which vehicle and which motor you have. I don't know where to get them, I bought mine years ago, but IMHO a lifesaver when it comes to this kind of job.

On the other hand LMK if you have another question, I'll do what I can...

BTW the haz and turn are also your brake lights in case you didn't figure that out. And I see that I left out tail lights. I'll check that for ya. Probably the only one left.:lol:

 

[skolman91]

Re: Wire ID

hmm so the haz/turn/brake lights are all on the yellow and green wires? I was considering tapping into the brake light wire to add a brake light somewhere but i guess that wont work if it also gets power with turn lights.. Thanks for the heads up

 

[Don W.]

Re: Wire ID

hmm so the haz/turn/brake lights are all on the yellow and green wires? I was considering tapping into the brake light wire to add a brake light somewhere but i guess that wont work if it also gets power with turn lights.. Thanks for the heads up

Yes, that's correct. That circuit goes through the turn sig sw and gets divided up as required. By the time everything gets to that connector its all been figured out.

IE are the brake lights superposed to be on? Brake on with left or right turn? Left or right turn w/o brake light? Hazard lights? All handled by a combination of the light sw on the dash, the brake light sw at the pedal, and the turn sig/ haz sw in the column.

 

[Don W.]

Re: Wire ID

I wanted to add that the term on the alt where the the two fuseable links go is also the main feed so-to-speak for the entire truck. A heavy wire (8ga min I would suggest.) goes from there to the battery, this charges the bat and provides the supply when the engine is off or the alt can't keep up for some reason. In a stock truck this wire comes off the the + bat cable at the bat. In my truck where I've moved the bat to the bed it comes off the bat term at the starter.

 

[skolman91]

Re: Wire ID

Did some more un-doing wire mess, more questions.. Im pretty certain the relay under the dash/steering column is for the fog lights correct? and their are two wires running out to the fog lights, green and purple/wht stripe. Which one is power and ground? thanks mr don w

 

[Don W.]

Re: Wire ID

Thanks but don't think I'm some kind of eggspurt. Just reading the manual. Anyway, you're correct. GM plays a trick here though. The relay oil is grounded through the high beam element of the LH headlight. What this does is cause the fog lights to go out when you turn on high beams. IOW for the fog lights to work the LH head light has to be plugged in and high/low beam sw on the column set to low.

To be sure on the relay in question there should 4 wires. BRN, PPL/WHT, BLK, PPL

 

[skolman91]

Re: Wire ID

I know youre just using a manual, but ask the guy with the instructions right..?
The relay im talking about has orange, green, 2-ppl/wht wires in one slot, and ppl, its just hanging under the dash.
The wires that are ran thru firewall to the fog lights are green and ppl/wht, wouldnt be surprised if this isnt orginal or messed with, after the firewall the wires are spliced at least twice with different wires/colors
I have a pic if youd really like to see, i can probably figure it out with a little more digging but thought they would be original and from the dash inward so i could just ask.

 

[Don W.]

Re: Wire ID

Ya, no problem, got the book just as well use the thing. :lol: There shouldn't really be any "non factory" type splices in those two wires. Grn and Ppl/Wht is correct. Hard to tell why someone would splice anything into those wires.

I know the relay you're talking about now. That should be the fog light relay.

 

[skolman91]

Re: Wire ID

I meant like someone has cut up the original ones then added on random wire.
In fact if you look at my second pic from first post on the top right you will see what those wires turn into once in the engine bay, red/ppl&blue wires is what runs down the fender..

So im guessing the green is the ground that goes to the LH headlight and ppl/wht is fog power?