79 AC Wiring help

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Nov 23, 2015 | 03:42 PM

Carpet

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79 AC Wiring help

I have a 79 the harness has three light and one dark green wires, one wire goes the compressor and the other two go to the pressure switch. But I have one of those light green wires that I'm not sure where it goes. I need some help finding out what this was does or go to. Thanks Jp

Nov 23, 2015 | 06:38 PM

DUB

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From: Charlotte NC

. You might need to get a wiring diagram for your car if you work on it yourself. Without spending a lot of time on the internet looking...I found this. This will give you an idea. The 1977 is basically the same due to the A/C-heater controls are about the same. The third light green wires goes to the resistor.

If your terminal ends are all cut off...look into getting a new A/C harness so you have all the correct connections...but that is up to you.

DUB

Nov 23, 2015 | 06:51 PM

C376FL

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From: Mulberry Florida

Quote:

Originally Posted by Carpet

Carpet I have a 76' if that wire comes of the harness close to the compressor it could go to the idle stop solenoid on the carb. I am not sure if 79' had them, just a guess.
Larry

Nov 23, 2015 | 08:01 PM

KapsSA

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From: Beecher Illinois

Quote:

Originally Posted by C376FL

Carpet I have a 76' if that wire comes of the harness close to the compressor it could go to the idle stop solenoid on the carb. I am not sure if 79' had them, just a guess.
Larry

On 79 to kick up idle when AC is on.......

edit, manual trans cars don't use it.

Last edited by KapsSA; Nov 23, 2015 at 10:22 PM.

Nov 23, 2015 | 09:34 PM

0Willcox Corvette

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Nov 23, 2015 | 10:20 PM

KapsSA

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From: Beecher Illinois

Noticed another thread of yours where you state you have a manual trans.
Manual trans cars don't have the solenoid kickup switch shown in my prior pic.
That green wire would possibly just be tucked up out of sight.

Nov 24, 2015 | 11:00 AM

Carpet

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ac clutch doesnt engaged

I found the third wire was cut and believe it goes to the Idle stop like C376FL stated. I filled the system with R134A but the clutch runs for about fifteen seconds and continues to cycle. The outside temp is in the mid 40 would this be causing the clutch to not stay engaged.

Nov 24, 2015 | 05:44 PM

DUB

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From: Charlotte NC

Quote:

Originally Posted by Carpet

Are you using gauges???

And you DO know that the amount of R12 that was used from the factory in this system (EXAMPLE 2.2 lbs)....IS NOT the same amount of 134a Freon you put into it. There is a percentage of what WAS installed is what you put in. Such as 75% of what was put in from the factory is what you pout in with 134a. BUT this also depends on other variables....which is why I asked about using gauges....to see what the high side is doing.

And yes...40 degree outside air temp..... can ...in my opinion...effect the result. Because honestly....who in there right mind would turn on the A/C when the outside air temp is at 40 degrees Fahrenheit. At that air temp ( 40 F)...it is right on the cusp of what the A/C system could put out if it is working perfectly on a hot day.

DUB