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JCI AC compressor mount and PCM/harness wiring questions


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I have some AC questions: I just received the JCI compressor and brackets. No instructions included, as usual. I will also preface this by stating that I am horrible with electrics.

1. Can someone post pictures of correct JCI mounting or a copy of instructions? I've seen several photos with various configurations and I also received 3 brackets instead of 2 that I expected:

 

 

nt6UQoCl.png

 

I also go SAE bolts instead of metric. I'll try calling or emailing JCI tomorrow for clarification, but it's kind of annoying.


2.  I have my harness sitting at WiringSpecialties waiting for an answer whether to wire in the AC hookup. This Sanden compressor has a single wire actuator. I am planning on cobbling together a Vintage Air setup based on what I've read on HBZ. JCI says the compressor hooks up to VA and that's it.

 

I would like the Camaro fans to be actuated by the PCM for AC, as well as miscellaneous functions like cut AC at WOT, raised idle, etc. Fans are my primary concern. How does this wire into the LS1 harness/PCM? Clutch ground activated via PCM and rest of the wiring is signal/+12v from harness/PCM to VA controls? As I mentioned before, I am horrible with electronics. 

Edited by auxilary
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If your LS1 computer runs the AC like most do have WS do the wiring, Compressor and tri-nary, VSS and probably a relay to the compressor.  There are two wires on the LS (from the relay) at the compressor for the AC, one is power to the compressor the other is ground.  The compressor grounds to the block so it should be OK.  If it bothers you run the ground to the compressor bolt.  

 

In order for the system to work you need to have the LS1 tri-nary switch also installed.  This is not hard at all.  It needs to go in the high side pressure line, either at the drier or in line on the hose.  The rest is done with the computer.  Have VA send a drier that is ready for the LS tri-nary or have them send the in line port or adapter for it.  

 

I will try to make it make sense.  There is a huge diameter wire on the Vintage Air, it normally runs to the AC compressor.  We run it to the AC request on the computer harness, which is a little bitty wire, THIS DOES NOT MATTER.  All the computer wants to know is 12V for AC request.  Once the computer has 12V it will check pressures in the tri-nary switch, engine RPM, VSS, WOT and several other parameters.  What this means is the AC will work great and the compressor will last as the computer shuts off the AC at WOT, for those stop light races and over 4500 RPM to save the compressor.  Computer also bumps the idle with IAC so when you let off and clutch the car does not die coming to a exit ramp.  A few other things it does is leaves the fans off until the pressures come up so the AC gets colder faster.  Shuts off the fans over 45 MPH unless the engine needs them, 45mph air is enough for the condenser.  I have not bought the JCI compressor and mount yet so I am no help on that.  

Hope the rest helps, Richard.  

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Thanks Richard, that makes sense. Once you mentioned the trinary switch I started doing some more searching/reading and I found this diagram which is fairly helpful at making sense. 

 

dUAxvyI.png

 

So the trinary switch is what will connect to the engine harness/PCM, and if I am reading this correctly, I can bypass the electric fan relay, fan temp switch, etc because those are all integrated into the harness. Blue wire from the trinary switch will go to the PCM hookup, and that's pretty much it. So the short version is yes, I need to get AC wiring from wiring specialties :)

Edited by auxilary
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Nevermind! I found one in my garage in the pile of lines I pulled from the donor Camaro years ago. The line's somewhat crushed but the pressure switch is there and can be salvaged or bought cheap on eBay (link). It looks like GM calls it the AC Refrigerant Pressure Sensor)

Edited by auxilary
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