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Old Mar 18, 2024 | 02:42 PM
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Default Unknown plug

Does anyone know where this 3 wire plug goes on an 81? It comes out of a wire harness by windshield washer pump fill up tube. I don’t see anything disconnected. Maybe an alarm or horn. Looks like it would connect to something mounted on top of left wheel well. My horn does sound a little whimpy like only 1 horn is working. Not sure if these 81’s came with 2 horns or where they are mounted.

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Old Mar 18, 2024 | 04:18 PM
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Cruise control unit is mounted on left inner fender on my 78. My wires wre long gone so I don’t know the colors.
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Old Mar 18, 2024 | 06:12 PM
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Cruise control is plugged in. Plus that connection is closer to the firewall.

Last edited by pete315; Mar 18, 2024 at 06:19 PM.
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Old Mar 18, 2024 | 06:33 PM
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Looking at it more closely, it’s not out of a wire harness. It’s taped to a vacuum line. The previous owner had an aftermarket alarm in car. I bet that’s what it’s from. I ripped all that stuff out.
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Old Mar 19, 2024 | 06:36 AM
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Could be that. Could be a lot of things.
seems people don't realise that the factory uses but one wiring harness for all cars of a certain make. There are ALWAYS connectors that are not used. We get a post almost every week on here, "Where does this connector go".
First question, Does everything work that is supposed to work? If yes. Why are you asking where a unused connector goes? Everything is working! Are you just trying to invent a problem?
these old cars give us enough issues that are real.
Rant over.
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Old Mar 19, 2024 | 08:34 AM
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First off, General Motors does not just add connectors if they are never going to be used. If they can build a car for 10 cents cheaper per car, they will. Second, I really doubt GM would tape a wire to a vacuum hose, but they could. It looks like a normal GM connector that I’ve seen a 100 times. Wires look old so they have been there for a long time. Can’t hurt to ask. I’ve been married 37 years, that ain’t no rant! You make a valid point.
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Old Mar 19, 2024 | 08:56 AM
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Do your Back-up lights work?
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Old Mar 19, 2024 | 09:52 AM
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Originally Posted by pete315
First off, General Motors does not just add connectors if they are never going to be used. If they can build a car for 10 cents cheaper per car, they will. Second, I really doubt GM would tape a wire to a vacuum hose, but they could. It looks like a normal GM connector that I’ve seen a 100 times. Wires look old so they have been there for a long time. Can’t hurt to ask. I’ve been married 37 years, that ain’t no rant! You make a valid point.
On my '72 w/AC, the factory instruction was to clip off the standard blower connector because it would be replaced by the one on the A/C harness (I believe that's the clipped one, but could be misremembering). I agree with 4-Vettes that there was one main harness that had connections that may not have been used. I believe the same thing happened with the dash harness and the power antenna connector in the C2. If in doubt, look up the AIM page to see if any option-related harnesses are listed for the main one. GM could certainly have used a single harness because it would cost more money to inventory and track supply for an alternate harness than keeping the 10¢ connector and associated wiring.

I also agree that it seems I've seen that connector before...
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