84 AC Wiring Help Please
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From: Brisbane
84 AC Wiring Help Please
Hi guys,
I'm sorting out some issues with my recently purchased 84 and am hoping you can help me with a question on AC wiring. I noticed a wiring loom with three plugs disconnected in the area of the AC compressor in the car. Here is a photo. From left to right I'll number them 1, 2 and 3.
So, I think plug 1 goes into the AC Low Pressure Cut Off Switch which I think goes here (the fitting is obviously broken and needs to be replaced)
Plug 2 appears to fit into the top of the AC compressor itself which I think is power
Now, plug 3 had me stumped until i looked at the back of the AC compressor and found something that looked broken at the pointy end of the screwdriver
Up close it looks like this
If anyone can tell me what goes in there, or even better if you have a photo or can give me a part number that would be great. I can see a cir clip in there so it must be a servicable part of the compressor.
Anyway, I just wanted to make sure I've got this correct and would appreciate any help you guys can offer.
Thank you.
I'm sorting out some issues with my recently purchased 84 and am hoping you can help me with a question on AC wiring. I noticed a wiring loom with three plugs disconnected in the area of the AC compressor in the car. Here is a photo. From left to right I'll number them 1, 2 and 3.
So, I think plug 1 goes into the AC Low Pressure Cut Off Switch which I think goes here (the fitting is obviously broken and needs to be replaced)
Plug 2 appears to fit into the top of the AC compressor itself which I think is power
Now, plug 3 had me stumped until i looked at the back of the AC compressor and found something that looked broken at the pointy end of the screwdriver
Up close it looks like this
If anyone can tell me what goes in there, or even better if you have a photo or can give me a part number that would be great. I can see a cir clip in there so it must be a servicable part of the compressor.
Anyway, I just wanted to make sure I've got this correct and would appreciate any help you guys can offer.
Thank you.
Last edited by 70chev; Nov 19, 2014 at 11:46 PM.
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Joined: Oct 2014
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From: Brisbane
The plug looks different to the one on mine, but I guess it could be because if is from a later model. Have no problem changing the plug over, just would like to make sure this is the item I need.
Thanks
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Joined: Sep 2004
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From: Mission Viejo CA
The Corvette Central 454645 is the switch on the left side of your compressor that turns on the radiator cooling fan relay when the a/c is actuated. That's plug #3 in your pictures.
1984-1989
This switch turns the radiator cooling fan on when the a/c system high side pressure reaches approximately 238 PSI. Air flow across the a/c condenser is imperative to prevent high side a/c pressures from causing system damage (blown hoses typically). When the a/c pressures go above 350 PSI so does the temperature of the refrigerant on the high side. The resulting temperatures can also damage compressor seals. The switch in the compressor is a normally open switch, at 238 PSI it closes latching the fan relay.
This switch turns the radiator cooling fan on when the a/c system high side pressure reaches approximately 238 PSI. Air flow across the a/c condenser is imperative to prevent high side a/c pressures from causing system damage (blown hoses typically). When the a/c pressures go above 350 PSI so does the temperature of the refrigerant on the high side. The resulting temperatures can also damage compressor seals. The switch in the compressor is a normally open switch, at 238 PSI it closes latching the fan relay.
Last edited by Hot Rod Roy; Nov 19, 2014 at 11:40 PM.
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From: Brisbane
Race Director
Joined: Apr 2002
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From: Anaheim CA
Plugs #1 and #3 on the '84 compressor are unique to that year and no other years have them. Those switches and connectors were moved to other places in later years.
Plug #2 is for the compressor clutch.
Plug #2 is for the compressor clutch.
Team Owner
Joined: Sep 2003
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The switch retained by the snap-ring is again what would have been a single pin switch that's been replaced by a 2 pin and yes it is the fan control. An original single pin would have been GM 2724279
I believe a very early number for the "kit" might have been GM 6595212 and could be on a shelf at a local dealer for maybe a reasonable buy. The newer replacement is very expensive from GM/ACD. Your connector is still the OE single pin and if it is OK. eBay for the OE switch if you needed it. There may even be OE stock on some older dealers shelves.
I believe a very early number for the "kit" might have been GM 6595212 and could be on a shelf at a local dealer for maybe a reasonable buy. The newer replacement is very expensive from GM/ACD. Your connector is still the OE single pin and if it is OK. eBay for the OE switch if you needed it. There may even be OE stock on some older dealers shelves.
Last edited by WVZR-1; Nov 20, 2014 at 04:32 AM.
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Joined: Oct 2014
Posts: 74
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From: Brisbane
The switch retained by the snap-ring is again what would have been a single pin switch that's been replaced by a 2 pin and yes it is the fan control. An original single pin would have been GM 2724279
I believe a very early number for the "kit" might have been GM 6595212 and could be on a shelf at a local dealer for maybe a reasonable buy. The newer replacement is very expensive from GM/ACD. Your connector is still the OE single pin and if it is OK. eBay for the OE switch if you needed it. There may even be OE stock on some older dealers shelves.
I believe a very early number for the "kit" might have been GM 6595212 and could be on a shelf at a local dealer for maybe a reasonable buy. The newer replacement is very expensive from GM/ACD. Your connector is still the OE single pin and if it is OK. eBay for the OE switch if you needed it. There may even be OE stock on some older dealers shelves.
Regards,
Darren
Team Owner
Joined: Sep 2003
Posts: 25,389
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Based on your location if you could source maybe Wells or an Airtex part these would be the 2 pin kit I believe
Airtex: 1S2817
Wells: SW3013
I don't know that those will help but it's maybe options. Either of those numbers would be the switch (2-pin) and also the correct connector in one box or that's the way I interpret the information.
Both of those will give results also on eBay, maybe something closer to you. GOOD LUCK!
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From: Mission Viejo CA
70chev, are you trying to restore your '84 to the factory configuration, or are you just trying to get things working again? As an alternative, your a/c wiring can be "re-designed" to eliminate these hard-to-find #1 and #3 switches.
A High Pressure Cut-out Switch (HPCS), your #1, could be installed anywhere in your high side line, or in the dryer, by a competent a/c repair shop. For the wiring, the 12 v. comes from the Function Control Switch (FCS) (dashboard) to the Pressure Cycling Switch (located at your evap. coil, near the firewall), to the HPCS, to the Compressor Clutch (your plug #2). Your plug #2 also has a green wire that goes to the Computer Command Control System.
Your plug #3 could be eliminated by adding a relay that is actuated by the 12 v. from your FCS. This relay would be wired to provide a ground (earth) signal to the radiator fan relay. Your a/c repair shop may be able to add a "trinary" switch in the high side line, which will provide both the HPCS function and the radiator fan relay control function.
A High Pressure Cut-out Switch (HPCS), your #1, could be installed anywhere in your high side line, or in the dryer, by a competent a/c repair shop. For the wiring, the 12 v. comes from the Function Control Switch (FCS) (dashboard) to the Pressure Cycling Switch (located at your evap. coil, near the firewall), to the HPCS, to the Compressor Clutch (your plug #2). Your plug #2 also has a green wire that goes to the Computer Command Control System.
Your plug #3 could be eliminated by adding a relay that is actuated by the 12 v. from your FCS. This relay would be wired to provide a ground (earth) signal to the radiator fan relay. Your a/c repair shop may be able to add a "trinary" switch in the high side line, which will provide both the HPCS function and the radiator fan relay control function.
Thread Starter
Advanced
Joined: Oct 2014
Posts: 74
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From: Brisbane
70chev, are you trying to restore your '84 to the factory configuration, or are you just trying to get things working again? As an alternative, your a/c wiring can be "re-designed" to eliminate these hard-to-find #1 and #3 switches.
A High Pressure Cut-out Switch (HPCS), your #1, could be installed anywhere in your high side line, or in the dryer, by a competent a/c repair shop. For the wiring, the 12 v. comes from the Function Control Switch (FCS) (dashboard) to the Pressure Cycling Switch (located at your evap. coil, near the firewall), to the HPCS, to the Compressor Clutch (your plug #2). Your plug #2 also has a green wire that goes to the Computer Command Control System.
Your plug #3 could be eliminated by adding a relay that is actuated by the 12 v. from your FCS. This relay would be wired to provide a ground (earth) signal to the radiator fan relay. Your a/c repair shop may be able to add a "trinary" switch in the high side line, which will provide both the HPCS function and the radiator fan relay control function.
A High Pressure Cut-out Switch (HPCS), your #1, could be installed anywhere in your high side line, or in the dryer, by a competent a/c repair shop. For the wiring, the 12 v. comes from the Function Control Switch (FCS) (dashboard) to the Pressure Cycling Switch (located at your evap. coil, near the firewall), to the HPCS, to the Compressor Clutch (your plug #2). Your plug #2 also has a green wire that goes to the Computer Command Control System.
Your plug #3 could be eliminated by adding a relay that is actuated by the 12 v. from your FCS. This relay would be wired to provide a ground (earth) signal to the radiator fan relay. Your a/c repair shop may be able to add a "trinary" switch in the high side line, which will provide both the HPCS function and the radiator fan relay control function.
Thanks for the advice, I genuinely appreciate it. I'm trying to get the correct parts and pieces if they are available. It seems switch #1 is OK and easy to find, but just not sure about #3. If I can find them, I'd rather source and fit the correct parts. Its definitely not a concourse car, but it is still a pretty clean and unmolested example of an 84 crossfire and I'd like to try to keep it that way at the moment. I do however appreciate your helpful hints and advice. Keep it coming.
Regards
Darren
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Joined: Jan 2020
Posts: 88
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From: Sacramento
original 1 wire / replacement 2 wire
Thanks Walepirot. Is this the part? Part number 454645 from Corvette Central.
Attachment 47842108
The plug looks different to the one on mine, but I guess it could be because if is from a later model. Have no problem changing the plug over, just would like to make sure this is the item I need.
Thanks
Attachment 47842108
The plug looks different to the one on mine, but I guess it could be because if is from a later model. Have no problem changing the plug over, just would like to make sure this is the item I need.
Thanks
I am on the same journey here. I have found the standard replacement parts are 2 wire or 2 pin where as the original is 1 wire one pin. I really don't want to install the old unit into the new compressor. Any suggestions on how to make the 2 wire work?
old broken single wire switch
old single wire connector