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73-87 Chevy _ GMC Trucks => Electrical => Topic started by: The-Pagemaster on October 31, 2012, 06:24:15 pm

Title: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on October 31, 2012, 06:24:15 pm
Here is 2 pictures of the first set. It got dark out so i will get some more pictures and edit them into the post tomorrow.

http://imgur.com/a/g5CNt

These went through the firewall but I have no idea what they would have connected to. One of them is a hose. The hose does go to some sort of switch on the break pedal.

I did trace one of the wires and it connected to this box that I think goes to the vehicle speed sensor.

1986 c10
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on October 31, 2012, 06:41:52 pm
That's the vacuum dump hose and electrical harness for the cruise control.  For an 86 or newer vintage, the cruise control servo mounts on a bracket at the left rear corner of the intake manifold.  Inside the truck, that harness plugs into the cruise module, a small black box containing a circuit board that mounts to the "convenience center" above the accelerator pedal.
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on October 31, 2012, 06:51:19 pm
cool Thanks. I will try to get some more pics up tomorrow of the other cut wires.   What is this "convenience center"?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on October 31, 2012, 07:17:28 pm
'Convenience Center' is the crazy name GM gave the mounting location for the cruise control module, the key warning/seat belt buzzer, and emergency flasher.  It's a small plastic chassis that attaches to the inside of the firewall right above and slightly left of the accelerator pedal mount.  Some techs refer to it as the 'electrical center.'  If you still have the cruise control assembly, you may be able to procure a new OEM service connector from ACDelco; or find the missing parts you need from the junk yard.
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 01, 2012, 05:45:36 pm
Here are some more. If you need better pictures let me know. Or need help on color identification.

http://imgur.com/a/eiwQj#0
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: velojym on November 01, 2012, 07:51:37 pm
Dontcha just *love* those butchers with their hack-n-slash techniques? (rhetorical question...)
 :o
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 02, 2012, 09:29:05 pm
Here are some more. If you need better pictures let me know. Or need help on color identification.

http://imgur.com/a/eiwQj#0

Based on where it exits the bulkhead connector, the dark green wire looks like the coolant temperature sensor lead for the dash gauge or light (ckt 35). 

Can you post an image of the bulkhead connector with the wires in question spread apart so we can clearly see which cavity each wire exits?  Three of the wires you've pictured are close enough in color that we need your help describing the wire colors and any associated stripes.

Is the vehicle far enough along that you can safely connect battery power?  Do you have a test light?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 03, 2012, 10:22:54 am
The vehicle runs. I have been driving it to work everyday sense i got it. I have a test light. I can get a closer picture. The reason im trying to find out what these loose wires do is to get rid of any I dont need and fix the ones I do. I hate seeing all these darn things hanging everywhere.  There is an aftermarket water temp gauge, oil pressure gauge, and ammeter installed where all the factory gauges use to be on the left side of the instrument cluster.

Ill post more pictures within the hour.
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 03, 2012, 11:21:59 am
http://imgur.com/a/rU7nd

I put descriptions for each picture in the album. If you have any questions let me know. Or need another picture.
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 03, 2012, 02:39:30 pm
http://imgur.com/a/rU7nd

The following are "best guesses..."

Pics 1 & 2)  The pink and black pair connect to the windshield washer motor.

Pic 3)  The left, lower orange wire may feed the dome & cargo lamps.

Pic 4)  The brown wire connects to the oil pressure sender (OPS) for the factory dash gauge.  If the green wire is the same green wire as the one in Pic 5, it connects to the coolant temperature sender (CTS) for the factory dash gauge.

Pic 5)  The brown wire is the OPS lead for the oil gauge.  The green wire is the CTS lead for the temp gauge.  The blue - you'll need to trace under the dash.  Could the pink/white stripe actually be tan/white stripe? ???  Need further clarification on which cavity it exits.   The pink/black stripe is ignition feed to various solenoids around the engine compartment and the ECM (although it appears that the 10-amp fuse for that circuit is missing from the fuse box - check it with a test light).
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 03, 2012, 02:43:05 pm
What engine/transmission did this vehicle ship with?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 03, 2012, 03:26:56 pm
8CYL,5.0,GAS,3SPD

Thats all I know about the original motor tranny. Is that helpful?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 03, 2012, 04:03:23 pm
8CYL,5.0,GAS,3SPD

Does it still have the 305 engine, emissions equipment, ECM, etc?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 03, 2012, 04:29:55 pm
From what i was told in another thread i made here the current engine is: 1970 350 engine 4 bbl 300hp turbo 350. Not sure about the current tranny.

what emissions equipment? that round canister next to the radiator? it was disconnected I pulled it out yesterday. Im not sure about the ecm or where it would be located.
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 03, 2012, 07:38:54 pm
So, all that's left on the engine is a PCV valve in one of the valve covers?

http://imgur.com/a/rU7nd

The following are "best guesses..."

Pics 1 & 2)  The pink and black pair connect to the windshield washer.

Pic 3)  The left, lower orange wire may feed the dome & cargo lamps.

Pic 4)  The brown wire connects to the oil pressure sender (OPS) for the factory gauge.  If the green wire is the same green wire as the one in Pic 5, it connects to the coolant temperature sender (CTS) for the factory gauge.

Pic 5)  The brown wire is the OPS lead for the oil gauge.  The green wire is the CTS lead for the temp gauge.  The blue - you'll need to trace under the dash.  Could the pink/white stripe actually be tan/white stripe? ???  Need further clarification on which cavity it exits.   The pink/black stripe is ignition feed to various solenoids around the engine compartment and the ECM (although it appears that the 10-amp fuse for that circuit is missing from the fuse box - check it with a test light).

Pics 4 & 5)  Since you're no longer using the factory dash gauges, you can dispense with the brown and the green wires.

Pic 5)  You probably no longer have a need for the pink/black wire (unless you think you might need low-current ignition power for something later).  I still need feedback on the 'pink with white stripe.'
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: The-Pagemaster on November 10, 2012, 04:04:38 pm
Sorry it has taken me such a long time to get back to you. Some things came up. But i do appreciate your help.

Yes the i checked out that wire and i guess fading has cause it to turn pink but on the end near the firewall it is tan as well as the end that was cut.

What could low current ignition power be used for?
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: bd on November 10, 2012, 05:07:00 pm
http://imgur.com/a/eiwQj#0 (http://imgur.com/a/eiwQj#0)
http://imgur.com/a/rU7nd (http://imgur.com/a/rU7nd)

The dark blue and the pink/white stripe wires may have connected to an oil pressure switch that was used for the electric choke.  The 305/350 would have been wired so the electric choke on the carburetor wouldn't start to open until the engine was actually running.  You can test this idea by momentarily grounding the dark blue wire with the ignition switch turned ON to see if the "CHOKE" light in the instrument cluster illuminates (assuming the bulb wasn't removed by the PO).
Title: Re: Bought a truck found some wires that were just cut. Quite a few.
Post by: Captkaos on November 15, 2012, 06:46:02 pm
The wiring diagrams have these labeled for the connectors...