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A/C compressor connector w/ resistor. . . Why?

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Old Oct 22, 2008 | 07:01 AM
  #1  
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A/C compressor connector w/ resistor. . . Why?

Hows it going? I'm in the process of replacing the engine harness in my '89 GTA (with the correct one this time lol ) but before I do, replace the dirty brittle factory convoluted tubing that protects the wires as well which I'm doing so at the momnt. Today as I was doing what appears to be the a/c compressor wiring, I noticed it had a few layers of dry brittle electrical tape wrapped around the connector were the wires go into it. I decided to unwrap it and found a small resistor plugged into both terminals of the connector. Anyone know why it was placed there? Heres some pics of what I'm talking about:

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Thanks in advance for the info!

Later,
Phoenix
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Old Oct 22, 2008 | 07:31 AM
  #2  
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From: North Central Mass.
Car: 1985 Berlinetta
Engine: Megasquirted TPI
Transmission: Transgo 700R4
Axle/Gears: 3.42
Re: A/C compressor connector w/ resistor. . . Why?

I believe it is a diode.

When you shut off a soenoid the magnetic field collapses and creats a pulse of current that can go back up the wires. If the compressor is attatched to something sensitive, say the ecm, it can fry things. The diode is there to bleed off the inductive pulse when the solenoid disengages.
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Old Oct 22, 2008 | 09:24 AM
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Car: '91 Z28 convertible
Engine: TPI
Transmission: T5
Axle/Gears: 3.27 posi disc
Re: A/C compressor connector w/ resistor. . . Why?

Toehead is right, it's the flyback diode that prevents the inductive spike from traveling up the wires to the ECM.
Leave it in there if you want to keep your ECM from burning up.

Lou
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Old Oct 24, 2008 | 10:42 AM
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From: Tucson, Az
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Re: A/C compressor connector w/ resistor. . . Why?

So the diode (not resistor) must be in there from the factory then correct? Since it was wrapped up in dry electrical tape and looked somewhat 'bootlegged', I thought someone might of put it in there due to an electrical problem they had or something. IMO, the connector and wires look like they need replacing so I'll look into tpiparts.net for a new one and wire it in b/c not even my old harness' a/c connector looked this bad lol. I'll definately leave it in for now since frying my new (rebuilt) ecm isn't an option. Thanks again guys.

Later,
Phoenix
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Old Oct 24, 2008 | 03:53 PM
  #5  
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Re: A/C compressor connector w/ resistor. . . Why?

I forgot to ask. Anyone know the part # to a new a/c pigtal connector like the one pictured? Thanks in advance.

Phoenix
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Old Nov 3, 2008 | 05:23 PM
  #6  
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Re: A/C compressor connector w/ resistor. . . Why?

I picked up a good used connector at the junk yard today and wired it into the harness. All systems go .

L8R,

Phoenix
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