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Old Nov 7, 2009 | 01:44 AM
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Default Wire Harness

I'm trying to figure out what these wires on my 74 corvette are for, anybody have any idea what these wire are suppose to go to?



I'm not sure if they are for the AC, the engine, or both?
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Old Nov 7, 2009 | 07:00 AM
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By 72 wires schematic
The 18g blue+ 12g orange + 12g purple wires should be in 3 contact connector that go to the AC relay.
Avner
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Old Nov 7, 2009 | 07:59 AM
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A PO removed the A/C system and left the wires hanging? Or....a PO started to change out the A/C relay and couldn't find the right one. Or....

Some of those wires are "hot" (orange) and should be taped-off if you operate the car.
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Old Nov 7, 2009 | 10:37 AM
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Originally Posted by avner
By 72 wires schematic
The 18g blue+ 12g orange + 12g purple wires should be in 3 contact connector that go to the AC relay.
Avner
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Old Nov 7, 2009 | 11:16 AM
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Does this car start because a few of those wires appear to be starter wires ?
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Old Nov 7, 2009 | 12:35 PM
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Originally Posted by ...Roger...
Does this car start because a few of those wires appear to be starter wires ?
The car does start and I see that one of those wires is connected to the starter, but which ones should go to the starter? I'm thinking of buying a new harness, but I don't know if I should by the AC, or engine harness? Are most of those wires for the AC? The guy I bought the car from told me that he removed the ac compressor because the clutch was bad, and left all those wires like that.
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Old Nov 7, 2009 | 05:13 PM
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use this to ID all those wires http://docrebuild.com/oosoez/8974101.html
Earl
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Old Nov 7, 2009 | 06:46 PM
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Originally Posted by jordan89
The car does start and I see that one of those wires is connected to the starter, but which ones should go to the starter? I'm thinking of buying a new harness, but I don't know if I should by the AC, or engine harness? Are most of those wires for the AC? The guy I bought the car from told me that he removed the ac compressor because the clutch was bad, and left all those wires like that.
The wire that I thought went to the starter was the large purple with no connector and maybe the red with the bare end connected to a small black.
The AC harness is separate from the engine harness. Follow the AC harness back and it should go through the firewall on the passenger side. If you follow the other harness it will go under the wiper motor and over under the brake master cylinder and connect at the bulkhead.
I would identify each wire to see what you have.

Hi Earl Docs diagrams are very good.
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Old Nov 8, 2009 | 12:27 AM
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Originally Posted by ...Roger...
The wire that I thought went to the starter was the large purple with no connector and maybe the red with the bare end connected to a small black.
The AC harness is separate from the engine harness. Follow the AC harness back and it should go through the firewall on the passenger side. If you follow the other harness it will go under the wiper motor and over under the brake master cylinder and connect at the bulkhead.
I would identify each wire to see what you have.

Hi Earl Docs diagrams are very good.
So the wire harness coming from the block under the master cylinder is only for the engine and has nothing to do with the AC wiring?
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Old Nov 8, 2009 | 08:06 AM
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Originally Posted by jordan89
So the wire harness coming from the block under the master cylinder is only for the engine and has nothing to do with the AC wiring?
The wiring coming "from" the bulkhead for the engine is not AC related,the heater blower orange wire should be in there but will be unused.
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