Wire Harness
Thread Starter
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
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?
I'm not sure if they are for the AC, the engine, or both?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
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.
Thread Starter
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
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.
Intermediate
Joined: Feb 2009
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From: anytown anystate
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
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 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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Thread Starter
Safety Car
Joined: Mar 2009
Posts: 3,558
Likes: 4
From: Oakland California
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.
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.
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
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.
