A/C 12V source for 5.3 swap

Buz said:
The quote below is from the Novak "Wiring and Powertrain.pdf"

A/C Wiring
The light green wire needs to be a 12V+ power source from the Jeep dash A/C control switch.
The light green with a black stripe goes through the pressure sensors and then to the compressor. This is wired in a series, into the first one, back out, through the next sensor and then to the compressor. The other wire on the compressor needs to be grounded. This should all be done with the factory Jeep sensors and pig tails from the old Jeep harness. The pig tail for the GM compressor is supplied with the harness.

What I was planning on doing was splicing the Novak green wire to to the DB/OR wire on pin 22 on C3 for the wire from the A/C control switch. The wire on Pin 22 has 12V+ when the ignition switch is in the ON position and the A/C control switch is in the appropriate positions. (Thanks goodness for the Power Probe tool )

I was then going to run the light green with a black stripe wire as described in the Novak text as mentioned above.

Do you think this would work as well?

It all looks great and thanks for posting the video. I am absolutely no good at that stuff.

I am going to try my hand at making the hoses if I can source all the parts. We'll see.

Buz
Click to expand...
I don't think this is right, the db/or gives a ground signal to the relay in the pdc which then gives 12v from a DB/BK wire coming out of C103. As I put in the video, I had to splice 1 and 22 from C3 to bypass the jeep pcm as it was doing funky things to the 12v signal. If I remember correctly, the db/or gives 12v when the a/c switch is OFF, which is opposite of what you need.
 
tj ac wiring.JPG
 
I miss-stated what I had in mind in the previous post. I was going to use the green wire from Pin 23 for the 12V+, but I went back and checked and it completes a ground and not a hot when the a/c switch is in the 1-2-5-6 positions as the schematic shows and the Power Probe indicates. I was too anxious to find an easy place to tie in to.

If I have it right, in the Jeep configuration, the pressure switches control the ground circuit before the A/C control switch. In the GM configuration, the pressure switches control the 12v+ on the way to the compressor clutch.

So, if you ran the light green wire (C90) through the high and low pressure switches, what did you do with the green with a black stripe wire in the Novak harness? Run straight to the compressor clutch?

I am thinking that if I do it the GM way, I will have to tie C90 to C13 somewhere near the C1 connector and then tie the green Novak wire to the db/bk wire out of connector C103?

Buz
 
Not sure why you would have to do it the "gm way", and I don't think you have to mess with c90 (I didn't touch it), are you planning to use gm style high/low pressure switches? The switches can work the way I did it or the way Novak recommends as they are just completing or not completing the circuit, not sure they care whether it's completing a ground or 12v circuit. Yes, in mine the green/black goes from novak harness straight to compressor. What is C13 and what does it do? It's not in the diagram.
 
I have about 1000 miles on my Jeep since l got it running. Nothing but very minor issues. Yesterday I completed about 90% of the wire loom. I de-pinned all of the unused wires in all the connectors. I don’t want to undo any of that. Thats why I am looking for different options.

Buz
6D27EAA0-4F59-45D4-B349-3F04620E4BE4.jpeg
 
Buz said:
I have about 1000 miles on my Jeep since l got it running. Nothing but very minor issues. Yesterday I completed about 90% of the wire loom. I de-pinned all of the unused wires in all the connectors. I don’t want to undo any of that. Thats why I am looking for different options.

Buz
View attachment 178828
Click to expand...

ah, that’s pin 1 of c3, I’m not sure what that c13 means but it’s not pin 13 or else the one to the left of that would be c90.
 
Longhorn84 said:
Makes sense. I think what you’re proposing should work if you plan to run the 12v signal through the switches.
Click to expand...
After looking at the different ways to wire it up and how I have my wires run and loomed, I think it will be least amount of back-tracking to run the ground through the pressure switches like you did. Thanks a bunch for sharing all your research and catching my mistake.

Also, after creating a material list, a tool list, and adding up the labor cost of things that I cannot do, the best option for me is to have the professionals do the a/c work.

Buz
 
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In case anybody else in the Houston area is looking for an excellent A/C shop, Custom Car Cool is the place to go. They did a great job with the A/C for my Jeep. Just as Longhorn84 suggested.

Buz

Final.jpg
 
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