Author Topic: What did these wires go to?  (Read 4729 times)

Offline m3talc0re

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What did these wires go to?
« on: December 23, 2016, 09:40:22 pm »
83 GMC Sierra Classic 305

On the firewall, left side of the engine, looking at it from the front, there is a bundle of wires cut and I have no idea what they went to.  Maybe the AC?

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« Last Edit: December 23, 2016, 11:10:20 pm by bd »

Offline Engineer

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Re: What did these wires go to?
« Reply #1 on: December 24, 2016, 07:08:41 am »
AC seems right. If there isn't any other wiring going to your AC I would have to guess that through process of elimination.
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
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Offline m3talc0re

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Re: What did these wires go to?
« Reply #2 on: December 24, 2016, 09:57:21 am »
I really wish they didn't cut all those XD

Offline zieg85

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Re: What did these wires go to?
« Reply #3 on: December 24, 2016, 10:14:57 am »
I may be wrong but that sure looks the the plug on a 1987 cab for the ECM on a TBI
Carl 
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Offline 1967KaiserM715

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Re: What did these wires go to?
« Reply #4 on: December 24, 2016, 11:39:15 am »
 ECM, AC should be more to the left.


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Offline m3talc0re

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Re: What did these wires go to?
« Reply #5 on: December 24, 2016, 12:04:46 pm »
Those go to the ECM? Wouldn't nothing work then?

Offline zieg85

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Re: What did these wires go to?
« Reply #6 on: December 24, 2016, 12:51:08 pm »
Those go to the ECM? Wouldn't nothing work then?

An ECM is for the TBI setup in 1987 suggesting you may have a 1987 Cab or firewall.  I just looked at both my 85's AC equipped and 86 non AC and neither has that hole in the firewall
Carl 
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1986 C10 under construction
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Offline bd

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Re: What did these wires go to?
« Reply #7 on: December 24, 2016, 01:35:23 pm »
Knowing the wire colors would help, but it's probably the ESC harness running into the ESC module under the dash.
Rich
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Offline 1967KaiserM715

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Re: What did these wires go to?
« Reply #8 on: December 24, 2016, 08:24:59 pm »
Knowing the wire colors would help, but it's probably the ESC harness running into the ESC module under the dash.
Esc, that's it, my truck had it, but nothing was connected, I've heard that it really doesn't do anything, but I'm not positive as I've never really looked into the esc modules.


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Offline Engineer

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Re: What did these wires go to?
« Reply #9 on: December 26, 2016, 08:04:26 am »
I really wish they didn't cut all those XD

That's the square body realm in a nut shell.

It seems every used 73-87 I have looked at has its wiring butchered by some hack at some point in its past. :(
2002 Chevy 2500HD 4x4 8.1/ZF6sp RC/LB
2001 Chevy 2500HD 4x4 6.0/4L85E EC/SB
1997 Chevy Blazer 4x4
1994 Chevy K-2500 4x4 C6P 5.7/4L80E
1979 Chevy K-30 4x4 4sp 4.10
1977 Chevy K-30 4x4 4sp 4.10 454

Dad of an Eagle Scout, and a Life Scout

Offline VileZambonie

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Re: What did these wires go to?
« Reply #10 on: December 26, 2016, 08:13:18 am »
Knowing the wire colors would help, but it's probably the ESC harness running into the ESC module under the dash.

ESC Harness
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10