700-R4...Wiring or no? Help identify a wiring piece.

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Hey all... I have wrapped up the rewiring of the truck, with one exception: There's a small harness coming from the firewall through a gromett next to the main fuse-block on the driver's side. It's got
blue, blue/black, and green wires.
My factory wiring manual lists it as going to "engine". If you trace it back, it appears to be tranny related. On the side under the hood, it plugs into another harness. That harness "Y's" off and has 2 connectors, one is a 4-pin connection (of which only 3 are used) that probably went into a vacuum switch. The other connector is a 2-pin job that looks like it also went to a vacuum switch. The 2-pin connector is red.
What is this? Will it affect the tranny in any way? I'm betting not, as none of my vacuum switches had any vacuum lines running to them before the fire. The vacuum switches that survived the fire still do not. (I may have just answered my own question, but it's 10:30pm, I'm still waiting on dinner to arrive, and I'm damn tired... and I just want to consult others before I decide that it's not necessary). How is the converter-lockup connected to the brake pedal? Would this harness be involved in any way?
I ask because there were many unidentifiable pieces of wiring under there for some time, and I've just about figured it all out.
FWIW, the closest thing to my engine that the manual shows is a California V6, where as mine was a Police K5, with a 305ci sold new in Tennessee.
Thanks,
~jp
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My s-10 blazer has a converter lockup switch wired to the brake pedal that un locks the converter when the brakes are applied. I found this out by accident one day when I ever so lightly rested my foot on the pedal while on cruise control. The RPMs went up but the pressure on the pedal was slight enough to not take the cruise control off line. Don't know if this helps you but my suspicions would be to keep the engine from stalling in a panic stop.
GM
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The 4 pin plug, is it square? If so it is the plug that goes to the left side of your tranny, gotta have it because it controls converter lockup. The two prong plug goes to the left side on your servo cover. Only used on early model 700's. I'll have to look but I believe it had something to do with a heater but don't quote me on that.

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and oh yea, it is connected to your brake switch. You want your tq converter to unlock when you hit the brake or else it would be like a standard without a clutch pedal.

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Well damn... I was hoping to have it towed to the tranny shop today, but I can't unless I have the wiring situation squared away.
I'll post a phote of it so we know for sure that we're talking about the same piece.
Where on the tranny would it plug in? Keep in mind that I don't really know much about trannies. Which side would it plug into? Is an '86 considered an "early" 700-R4?
~jp
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Actually...now that I think about it...
The 4-pin connector went (most likely) to a vacuum switch somewhere on the rear passenger side of the engine bay. It's attached to the firewall, near the top. It run close to the brake booster and DOWN to the little 3-wire harness that exits the cab through the firewall, right next to the fuse block.
I will take a pic at lunch (within an hour or so) and post it.
~jp
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86, that shot the idea of 2 wires running in by the band apply servo. But there still is a square 4 hole plug on the drivers side up on the ledge above your pan. should be easy to spot because it protrudes above the tranny case.

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And thinking some more the wire I previously thought went to the servo side was a one wire plug. But that doesn't apply to a 86. Iv'e only seen them on trannys with aux valve body and 27 spline input. I still haven't checked but I THINK it was a heater that worked something like a choke heater. Posting this useless to you information hoping someone refreshes my memory.

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Check this out: http://absolutepickens.com/Harness.html
The 1st and 2nd pics are the same, just zoomed in one the 1st...You can see in #2 how it leads back toward the firewall. AC compressor is behind my hand...wires lead to the firewall, next to the brake booster (toward the passenger side).
Pic #3 shows me holding the harness from the connectors, somewhat tightly. You can see that both come together in a "Y" formation, to the right of the carb, and they stay directly to the right of the blue loom all the way back to the firewall where they're attached. Like I said, IIRC, at least one of them originally went over to a vacuum switch more on the passenger side.
Pic #4 shows where they attach to the firewall, and the connector that terminates the harness. It it supposed to go over the brake booster and attach to...
...the connector in Pic #5, with the green, blue, and blue/black in my hand (black stripe not visible in pic). That little harness comes out of the firewall next to the fuse panel. The single-conductor, orange connector is attached to one of those 3 wires, and the wiring manual lists it as a "test" connection.
Any ideas?
~jp
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Here's the wiring diagram pics along with the real pics... may explain a little more.
The first pic shows the 3-pin connector coming from the firewall... it's outlined in red, and that "test" connection is up top (somebody routed it through the firewall).
http://static.flickr.com/51/152091094_0e060e0740_o.jpg
as seen here:
http://static.flickr.com/50/152016101_80ce89af19_o.jpg
This is the other end (in red). The wire numbers do not match up, but this is exactly what my factory wiring manual shows... That 4-pin connector is listed as going to the the "T.C.C. Solenoid". Where is that??? Can't be in the tranny...gotta be under the hood somewhere, because the harness would never reach that far.
http://static.flickr.com/54/152091095_2431c1a02c_o.jpg
seen here:
http://static.flickr.com/56/152016092_1d62e2a53e_o.jpg
(white connector)
Where the harness makes a "Y", it goes here:
http://static.flickr.com/48/152091096_580d78705b_o.jpg
(same pic as above, but the 2-pin red connector)
On the right you can see the 2-pin connector, listed as connecting to "Closed Loop Carb Control". On the left, you see the 3 wires going to the connector in the 2nd diagram.
So... what is "Closed Loop Carb" and "T.C.C."??? Is TCC "torque converter *something*"?
~jp
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>Ok 1st and 2nd pic. 4 pin is to tranny. Drivers side above pan lip. 2 wire

Hmm... the other end of that harness is INSIDE the truck, and does go to the 4WD indicator as far as I can tell... I don't think that 4-pin connector could reach the transmission. From the firewall, it only reaches about as far as the AC compressor.
Besides, there's a screw eyelet attached to that harness close to the plug and I didn't unwire anything under there.
The yellow and blue wires on the 2-pin connector are tied directly to the yellow and blue on the 4-pin. The 4-pin only uses 3--yellow, blue, and blue/black. The colors differ from the wiring manual for some odd reason.
No cruise control on this truck. It's a Custom Deluxe--meaning neither Custom nor Deluxe, lol.
Keep this in mind... the closest thing that wiring manual has to my STOCK setup is a California V6, where mine was a Tennessee (new) 305ci, Police truck. Don't understand that...but the manual doesn't have a California V8 listed. Maybe from the wiring perspective they're the same? I still *think* that the 4-pin went to a vacuum switch or something, but it's hard to say since so much was literally roasted in the fire.
Any ideas on the T.C.C. or Closed Loop Carb?? I do remember the old Quadrajet having a connector or two on there.
Thanks for all the help you're providing.
~jp
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Jon R. Pickens wrote:

================== I refer you to your pic........
http://static.flickr.com/56/152016092_1d62e2a53e_o.jpg
(white connector)
The connector closest to the tip of your finger goes on the trannies case connector. (plugs into connector on tranny)
fact.....not fiction
The TCC solenoid is located inside the transmission.
TCC = Torque Convertor Clutch
TCC sol. aka Lock-Up solenoid
Closed Loop = in simple form, that the computer is in an "on" state and controlling the air/fuel ratio.......as well as other things, such as the lockup of the convertor in the tranny.
Closed Loop Carb controll = refers to the fact that the vehical should have come from the factory with a somewhat electronically controlled carb. AKA feedback carb. Which, it sounds like you may not still have on the vehical.
I will now drink my coffee, and go re-read the post from the beginning,
take a tylenol, maybe have a smoke, then try to offer up some more insight.
hopefully informative,
~:~ Marsh Monster ~:~
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Marsh Monster wrote:

Ok... I don't recall unplugging it and didn't think it'd stretch that far, but I'll be pulling the harness and repairing it as needed today.

Gotcha...that's what I've come to understand after doing some searching online.

Yeah, the original Quadrajet had electronic connections on it. I'll just remove the portion of the harness that went to the carb, as it wasn't hooked up before the fire. It simply splits from the 3-wire portion of the harness.

Informative indeed...
~jp
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Ok... after studying the wiring schematics closely, I think I made some sense of it.
The problem is, the FACTORY wiring manual doesn't have my exact engine configuration listed.
It shows 3 wires going to the transmission, with one being interupted by the Closed Loop Carb control (on that online schematic). The CLCC hasn't been there for a while, so does this mean that only (2) wires need to be connected?
I checked at lunch time, and that harness is just exactly long enough to make it down to the tranny. Maybe I did disconnect it, but I don't remember it.
I am WAY behind schedule here. Truck should've been at the tranny shop 2 days ago.
Thanks,
~jp
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Oh yeah... How did the carb affect tranny operation?? (just curious at this point).
~jp
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. . ============Jon R. Pickens wrote:

============ In short form...........
Torque Convertor Lockup "timing" is directly linked to the amount of throttle opening.
The computer senses how much foot you lay into the pedal, and allows lockup when eng. rpm, mph, and other eng. related data tell it that it's time to do so. The computer will imediately unlock the torque convertor when it senses you have stomped on the pedal.....such as passing situations.
again......the short form.
you know........ the tranny shop should be able to make short work out of that 3 wire connector for you as part of the tranny job. There's even a way to bypass the computer controlling the lockup all togeather, and the tranny shop should be able to do it for you as part of the rebuild. Just a suggestion....in case.....you don't have anything telling the computer......how much foot your putting in the pedal.
:)
~:~ Marsh Monster ~tranny tech~ ~:~
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Thanks Marsh...
I agree, the tranny shop should be able to work with me on this. I know there's a kit available from TCI that allows lockup to be controls without interaction from an ECM, and I think their solution is a vacuum switch (IIRC).
The tranny doesn't *have to* lock up for now though...
~jp
Marsh Monster wrote:

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. . ==========Jon R. Pickens wrote:

================== Jon, here's a site you may want to cruise around. There's a decent link in the toolbar on the bottom, take a look at the lockup link.
http://www.highperformancecars.com/crosley/shrtbolt.htm
yw
~:~ marsh ~:~
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oh yeah.......
and i clicked on yer site.......
nice guitars, and the other pic ain't bad either. <g>
~:~ marsh ~sips his mushroom tea~
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