72 K20 unknown wire??

[AASmedic]

Does anyone know what this connection is for?? Its very short.

[AASmedic]

Sorry, couldn't get it upright. Its part of the engine wiring harness.

[Stocker]

I'll be watching this thread. My truck has the exact same connector and I'm pretty sure it's never been hooked up to anything in the 39 years I've owned it.

[davepl]

Can't tell from the picture what color it is.

[AASmedic]

Brown, if I remember correctly

[davepl]

Any chance you can post a SPID pic? Could be the tie-in for cab lights, for example, but I don't know how the truck is equipped.

Easiest way to know for sure would be to follow it back to the fuse bulkhead and let us know which cavity it comes out, that way we could determine what it's most likely for. From position and color it's tough to know...

[BlueBullet]

I think that has something to do with the emissions on the original intake. There was a wire that ran over there from passenger side of the intake. Not 100% sure.

[AASmedic]

Well, looking at the SPID, there is nothing indicating cab marker lights and as far as some thing from the original intake...it still has the original intake. Can't find where it would connect. It plugs in at the firewall abd is part of the engine harness.

[57taskforce]

My 72 K20 has that same wire unhooked. Not sure where it goes but the truck runs fine with out it so I never put much thought to it.

[gable74]

If it has a sunroof its probably the seat eject wire?

[AASmedic]

The wire is brown with a white stripe. It enters the fuse block with a larger gauge purple wire.


No indicators here

[davepl]

FWIW, I found in another thread: "the brown/white wire you describe runs from the key switch to the firewall block on the diagrams I have. It is joined there by a solid brown wire that runs back to the cluster plug to pin 8 on the idiot light dash. It is used to feed the alternator field exciting circuit through the regulator.The ammeter dash does not have this wire."

If you had gauges, I'd makes a guess that that's why its not connected, but I don't think you do, so I'm still at a loss. Swing and miss for me I'm afraid!

[AASmedic]

Thanks for the input

[Stocker]

Originally Posted by davepl

If you had gauges, I'd makes a guess that that's why its not connected, but I don't think you do

Maybe he does, and your guess may be spot-on. SPID shows YE9 package. I found this in an old thread:

Originally Posted by Harold Shepard

Straight from GM.... April 1971 new package avaiable Cheyenne Super Option production code YE9.. Features all of the options included in the Cheyenne Option Z84 with the addition of the following: Bright hub caps RPO p03, except dual wheel, body upper side moldings RPO B85 - fleetside only, bright metal tailgate latch- fleetside models only, cloth and vinyl seat trim- bench seats only, houndstooth pattern in parchment and black, blue and black, and olive and black- replaces all vinyl Z84 trim, color-keyed floor carpet- black, blue or olive, instrument cluster with RPO Z53 guages and wood grained cluster face, glove box door name plate- Cheyenne super, wood grain treatment on glove box door. Interior codes: Code 2 blue/black, Code 8 olive/ black, Code 9 Parchment/ black.... Production began in April of 1971.... Available on all series 10-30 pickups and chassis cabs. Information taken from sales flyer/ad from GM.

[rsmarr1982]

I have that same wire on my 72 k20.

[AASmedic]

Thanks mike, that's helpful. What gauge would it have gone to?

[GR8-68]

That is where you hook it to the computer diagnosis

[57taskforce]

Mine has gauges as well. That would make sense.

[stsalvage]

And they call you guys Chevy guys.OK if none of you had a 1971 chey truck you probable don't know this smog option Its was the trans spark controller it has a dash pod up next to the front of the carb on the passenger side there are 2 relays on the fire wall 2-3 inches away from the driver side spring there is a harness that splits off and connects to the 2 prong relays and goes back in to the plastic wire protector comes out 2 wires with a 2 prong plastic plug to connect to the dash pod 1 wire goes from the dash pod down the engine down the trans to something.I think i have a pic of it let me check

My only problem to most of you guys trying to put your truck back to factory 98.9% of you will never go completely back to factory.

That experiment was a one off wonder.Most of you PULL ALL THE SMOG parts off your trucks any ways.

Now getting past that most people use that wire for a under hood light cus it has 12 volts to it until the key is turned off.

Some use it for a hood light and they use it to power there electric choke for your Edalbrock or holly carbs.

My pics are not that good showing it cus its something most of us GM guys don't Care about or the true GM guys do.

The guy that most of you should talk to about Junk parts that should not be used on GM trucks is the LONGHON MAN There Are disconnected parts on all GM cars that where a BAD IDEA.

GM DID IT CUS THE EPA WANTED IT DONE THERE WAY.

We all know are government Sucks when they think metaling in are car's performance.

at one time they thought headers was a smog problem.running a bigger carb was bad for are Air.

THE EPA dose not talk to any one in the the Performance department on how a engine runs better then the guys that do it for a living

[stsalvage]

here is some more of pics of the old carb and that dash pod