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73-87 Chevy _ GMC Trucks => Electrical => Topic started by: silvrbreez on October 18, 2008, 10:08:08 AM

Title: Wiring Cleanup...'83 C10 SWB Stepper
Post by: silvrbreez on October 18, 2008, 10:08:08 AM
Alright guys, looking for some insight from some seasoned vets.

I'm going through the truck and trying to simplify it as much as I can without affecting the driveability.  In doing so, I'm finding quite a few wires under my hood and dash that run to nowhere.  Below are a few pics of the connections/wires I've found so far that I can't describe.  I think several of them have to do with what used to be a cruise control system.  It was defunct and broken so I removed it, now I need to get rid of all the wires that go to it.

Any help you guys can provide in identifiying these wires would be a huge help.  Here are some pics, with some brief descriptions of what I think the wiring is for...

1. BLUE and PINK/BLACK wire plugged in below the steering column.  (Cruise Control?)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18001.jpg)

2. Here is where the PINK/BLACK wire from Photo 1 goes into the fuse block.  (Cruise Control?)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18002.jpg)

3. Here is where the BLUE wire from Photo 1 goes through the firewall.  Also you'll see where there is a GREEN wire that also goes through the firewall, but it runs to an unplugged connector.  (Cruise Control?)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18003.jpg)

4. Here are the BLUE and GREEN wires coming through the firewall to the engine.  (Cruise Control?)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18004.jpg)

5. This photo shows the connectors on the end of the BLUE and GREEN wires in Photo 4.  When plugged in, these wires join up to the connector at the top of the pic which is attached to a harness that leads down the firewall and appears to "T" into another harness running possibly to the transmission.  (Cruise Control?)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18005.jpg)

6. Here is a loose wire connector leading towards my AC compressor.  I have no idea what this one is.
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18006.jpg)

7. Here is the path of the loose wire from Photo 6 back to and along the firewall.  No idea here.
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18007.jpg)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18008.jpg)

8. This connector has electrical to one end and a vacuum line into the back of the intake on the other end.  Also notice another loose connector plug in the right of this photo.  No idea here.
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18009.jpg)

9. This connector has a long lead wire from down on the back side of the engine.  Seems like a factory connection that may have lead to the original electrical water temperature connector.  The previous owner rigged up an aftermarket mechanical water temperature gauge and left all the old stuff hanging around.  That'd be my guess for this one.
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18010.jpg)
(http://i175.photobucket.com/albums/w126/silvrbreez/83%20C10/08-10-18011.jpg)
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: GoatBeard on October 18, 2008, 11:40:23 AM
That last picture -- I believe that one hooks to the block between the 1 & 3 sparkplugs.  Look between those two plugs and you'll see where it goes.  I can take you a picture if you need me to.

Most of the others aren't plugged in on mine, either -- so I can't help with those, although I'm interested to hear where they go.   :)
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: GoatBeard on October 18, 2008, 11:49:28 AM
I added the picture but then couldn't edit the post.  Anyway, I may be wrong, because it looks like you've already got that wire running to the sending unit, but I think that's for your temp gauge.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: silvrbreez on October 18, 2008, 02:10:17 PM
Yeah, like I was saying, the previous owner installed a mechanical sending unit and just left the stock electrical gauge installed.  I'm sure you're right that it just goes there, and that was my first thought for that one.  Good news is though, if I wanted to swap back to the stock electrical gauge then all I'd need is a new sending unit.

Anybody got any thoughts on the other plugs/wires?
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: choptop on October 18, 2008, 02:48:45 PM
The switch in pic 8 I believe is the lock up for the torque converter
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: hotrod24 on October 18, 2008, 02:59:42 PM
mine goes stright to my engine harness from the block
That last picture -- I believe that one hooks to the block between the 1 & 3 sparkplugs.  Look between those two plugs and you'll see where it goes.  I can take you a picture if you need me to.

Most of the others aren't plugged in on mine, either -- so I can't help with those, although I'm interested to hear where they go.   :)
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: GoatBeard on October 18, 2008, 05:36:18 PM
The switch in pic 8 I believe is the lock up for the torque converter

What in the world does that do?  Sounds important...
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: VileZambonie on October 18, 2008, 05:46:13 PM
The low vacuum switch is used to unlock the torque converter clutch. When the vacuum signal drops the converter is unlocked.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: GoatBeard on October 18, 2008, 05:52:23 PM
::scratches head::

What's that mean in english?    :D
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: VileZambonie on October 18, 2008, 07:23:51 PM
When engine load is high the torque converter cannot be locked. The torque converter lockup piston locks the engines crankshaft to the transmission input shaft essentially. This increases efficiency due to thermal loss. Energy converted from mechanical energy into heat energy dissapated to the air is wasted. The 10% or so slip between the impeller and turbine is also an unecessary loss at the coupling phase of the torque converter. So it is designed to increase economy however cannot be locked during high engine load and when torque multiplication is needed. When you step on the gas and open the throttle plates engine vacuum drops and this signal is sent to a switch that opens the electrical circuit and unlocks the torque converter clutch.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: silvrbreez on October 18, 2008, 10:02:34 PM
VileZambonie: Thanks for the ID.  Just to be clear, you are talking about the part that has the vacuum line coming from one end and the wires coming from the other correct?  You are not referring to the loose/disconnected plug in Photo 8?

Any idea what any of those others might be?
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: Prong on October 19, 2008, 02:52:52 AM
I'm pretty certain the plug by the A/C compressor is for an Idle solenoid that goes to the carb. It'll kick on when you hit the A/C to keep the idle up.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: GoatBeard on October 19, 2008, 08:30:15 AM
Thanks Vile! :)  My last question is this, is it bad (or will it hurt anything) not to have that hooked up?

BTW, what year is your truck?  Early 80s?
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: silvrbreez on January 04, 2009, 07:44:00 PM
Bringing this one back from the dead and reusing it for the pics in my first post.  Still working on trying to clean up some of this stuff.  Bear in the mind the truck runs GREAT with all of this in the condition it is now, so I'm not sure what is loose and unplugged is even needed or being used?

Anybody else got anymore thoughts on the loose and unplugged wires in those pics?

So far, a couple have been identified and others remain unknown.  Below is the number for the pic with the ID and my thoughts in parentheses.  I've added a little more description where I could.

1. (Cruise Control???).  These wires appear to go into a connector that is plugged into the brake light switch.  Does that make any sense?

2. (Cruise Control???)  The upper of the two faded plastic plugs is the one in question.  Any ideas?

3. (Cruise Control???)  Blue and green wire here (green with plug connected to nothing) are shown here from the inside penetrating the firewall.

4. (Cruise Control???)  The same blue and green wires from Pic 3 are shown here where the come out of the firewall into the engine bay.

5. (Cruise Control???)  The two connectors laying on top of the master cylinder reservior come off of the blue and green wires in Pic 4.  The connector to the right on the bottom of the pic hooks into the connector I am holding.  The connector to the left at the bottom is just sitting there unplugged.

6. & 7. Lead to Idle Solenoid that goes to the carb.  It kicks on when the A/C is on to keep the idle up. (provided by Prong).
Any idea where I can get one of those Idle Solenoids, or can someone help me track down if I already have one and it's hiding?

8. The connection to the leftt of the pic is Vacuum switch to unlock the torque converter clutch (provided by VileZambonie).
Any idea what the unplugged connector to the right of the pic is?

9. Plug connector for electrical water temperature sending unit (provided by GoatBeard)

Again, any help is much appreciated.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: eventhorizon66 on January 04, 2009, 11:52:48 PM
As far as pic number 8 goes: On my truck that is not the vacuum switch for the TCC.  The wires went to the ECM only.  My TCC vacuum switch is located directly above the brake booster.  Here's a pic of my engine bay back when both switches were present (now the left switch has been deleted).  Oh, and the wires that hook up to the TCC switch are light green and light blue.  The blue wire should lead to a brake switch that unlocks the torque converter everytime you depress the brake pedal.
(http://i208.photobucket.com/albums/bb247/1985C10/P7080065small.jpg)
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: KoolerSL2 on January 05, 2009, 12:08:15 AM
that switch in pic 8 i from my experience is called a Tip in switch.
controls the computer controlled distributors.
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: silvrbreez on January 05, 2009, 09:22:02 AM
As far as pic number 8 goes: On my truck that is not the vacuum switch for the TCC.  The wires went to the ECM only.  My TCC vacuum switch is located directly above the brake booster.  Here's a pic of my engine bay back when both switches were present (now the left switch has been deleted).  Oh, and the wires that hook up to the TCC switch are light green and light blue.  The blue wire should lead to a brake switch that unlocks the torque converter everytime you depress the brake pedal.

Sounds like you described the blue and green wires I show in pic 1, 2, 3 and 4.  The blue wire does go to the brake switch.  It's tied in with that pink wire that goes to an ignition lead on the fuse block.  I guess those go together for that, but the green wire just lies inside the cab unplugged as shown in pic 2 and 3.  What does that connection look like under your dash for the green wire?
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: oldwhity on January 05, 2009, 12:04:17 PM
Silvr, my truck is an 81. The lt.blue and lt.green wire coming out of the firewall going over the break booster and down to the tranny controls my backup light switch. The only thing different is that my blue wire is dark blue(maybe cuz mines a 4sp). The pink and black wire coming off of the panel go up to the gauge cluster. Mine doesn't have the connector off of the steering column.

I was looking through my Haynes manual and none of the wire schematics show a lt.blue and lt.green wire from the firewall or your panel box setup. I even looked under the 6cyl schematic just in case it was converted but got nothing. Good luck!
Title: Re: Wiring Cleanup...'83 C10 SWB Stepper
Post by: eventhorizon66 on January 05, 2009, 01:53:07 PM
What does that connection look like under your dash for the green wire?

My green wire doesn't make it back through the firewall like yours.  It lies unconnected near the brake booster, so I think you're OK there.