2G A/C system not working

[cswindel]

Alright electrical nerds I need to be graced with you assistance as I am no good with electrical.

Current situation:
- A/C is not blowing cold air although the system has been charged recently without the system actually pulling in r-134 because well it dont work haha
- I dont have any prior knowledge of whether it worked or not before or after my teardown of the car
- As a side note I am running OHM harnesses throughout the engine bay and interior and running ECMLink v3

Current untested areas and possible theories:
- A/C compressor is dead and I have not ran 12v power to it such that I can test if the clutch engages or not
- Seeing if there is a setting in ECMLink that I am missing since the a/c and rad fan both kick on when signal for rad fan to kick on gets pushed out
- Thermo sensor is poop but havent checked and the wiring diagrams confuse me on where it is physically located behind the glove box and there arent really any pictures when i look.
- ACCU is poop but havent checked and not sure which wires in the connector to check but havent dug into that area yet because its a pain to reach

Steps I have taken thus far:
- Checked continuity from ECU pin 22 to A/C compressor relay in fuse box (Good continuity)
- With key in ON position and engine not running, I have voltage going to the a/c fan (connector A-39), Dual pressure switch (A-47), and the A/C compressor (A-95)
- With the engine running I checked for voltage at the same connectors and nothing concerning
- With the engine running and a/c switch active I checked voltage again and still nothing concerning. A/C compressor ground showed grounding too.
- With the engine running, I jumped/bypassed the dual pressure switch and no result came about from that
- As mentioned prior, I noticed that the a/c fan and rad fan kicked on at the same time when the signal for the rad fan got passed through the circuit (I dont know if this is normal or not but hey 2 fans is better than 1).

Just wanting to see what your inputs are with this matter before I start going down unnecessary rabbit holes without much guidance (because I will get lost, sad, and confused and it might all occur simultaneously). I believe I have covered the majority of what I have done and assessed to get this thread rolling at least

 

[Vladimir]

Also here is a simple theory of operation onto what is happening . When you hit the a/c button power gets sent to the Auto air conditioner ECMtunning (black box) power comes out of the black box and goes towards the pressure switch and into the condenser fan relay. Ones the pressure switch has pressure it closes the circuit and sends power to the a/c compressor relay and also to the ECU. ECU sees the power and gives ground to the a/c compressor relay and the relay makes circuit sending power to the clutch. This is what it most likely looks like according to all diagrams I just want you to see it same way. I can highlight the diagrams for you. If you want? Also take the plug of from the press switch and touch the two pins the should be continuous with zero to no resistance since we have pressure in the system. Lmk

 

[cswindel]

Well it looks like they did some weird stuff again and left out a wire for pin 42 but I have 22 and 45 with 45 having 2 wires. 22 does have continuity with the relay

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[cswindel]

Im reading 0.04 ohms on the pressure switch itself

 

[Vladimir]

Good. Almost zero resistance indicates that the pressure switch made circuit. It sees the pressure and work as intended.

We will continue. Just give me some time. I'm doing gigs again

 

[Vladimir]

Also if pin 42 wire is missing the a/c clutch will never get triggered, because that pin according to the diagram goes to intermediate pressure switch, which is probably another stupid way of saying dual pressure switch. Please verify that indeed 42 is missing

 

[cswindel]

Yeah there is no pin 42...the more I have troubles with this harness the more I hate how much money I spent

 

[Vladimir]

Ok, great. We might have located the main issue. Please don't try to hardwire anything in yet, we will do more testing because there is so many variables that are still unknown. I'll get back

 

[Vladimir]

This is my theory. Since all the colors of wires are wrong, because the harness has changed, and all the pins on the diagrams have different numbers only thing we can assume is this, pins 22, 42, and 45 are as followed.

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What we can do next is check the power coming out of the automatic a/c controller (black box). The wire that I've highlighted in yellow.

You mentioned before that you have 12 volts available at the dual pressure switch connector. We have to verify at which pin is the voltage present and verify the source that actually sent that voltage there.

Disconnect the connector from dual pressure switch. With the ignition on or the car running, command the A/c to be ON. With a power probe or your voltmeter verify which one of the 2 pins gets 12v. It should only be one wire.

Once you verified the wire, turn off ignition and trace the wire back to its source(Continuity test). It should be going to the little black box that is under the glove box. There is a possibility that the wire color might be green/orange at the black box connector since I doubt OHM racing harness extended all the way to there.

Tell me if the power is confirmed to be coming out of the black box, going to one of the two pins on press switch.

Also do you have anyone on here or any friends with a 2nd gen that can verify that their ECU has pin 42 going to one of the pins on the pins on the dual press switch connector?