Need help with A/C

[A4INGS]

Hey guys- I'm hoping for some help in diagnosing my A/C problem.

Symptom: It doesnt blow cold.

Here is what I have checked:
Compressor does not turn on when on max A/C.
Low side shows overpressurized, but that may be due to compressor not being on.
Ran VCDS. No Codes, other than recirc flapper.
Ran VCDS test. it DOES make the compressor turn on, but then shows an error. No real help, other than proving that there is power to the comp.
Replaced the pressure switch with one from the junkyard- did not help.
Replaced the 267 relay with one from junkyard- did not help.

SO: I do have power to the compressor, and its not low on refrigerant. Should I try to bleed some refrigerant from the system to bring it into the "green" range? Also, why would the low side pressure be too high? I've never charged the car.

Any advice/help would be appreciated.

[a4kamila6]

Yes if you changed the clutch relay and the compressor itself, id recommend recovering the excess refrigerant if you have a recovery machine and tank. if not, purge a little till you are in the specified PT zone for 134a at the ambient temp. i would also check the high side sensor mounted on the condensor and the orifice tube located in the high pressure pipe.

[A4INGS]

a4kamila6, thanks for the response. I let refrigerant out until I was in the green zone. Still no dice.

I have done some more troubleshooting:
I tested the 267 relay and it functions as normal.
I found that the (+) wire that was leading to the compressor was damaged, so I spliced in a new wire.
The low side now shows normal pressure.
The compressor comes on when connected directly to (+).

After testing the relay, checking low side pressure, and swapping the high pressure sensor with a replacement, what is there left to do?

[a4kamila6]

You have to check the high side pressure also because if one side is abnormal, it can help you determine if you have a leak, a restriction or etc. I doubt you have a leaky evaporator. At this point its just a process of elimination. You verified compressor wire is fixed, relay and sensors work, freon charge is good... Maybe check the orifice tube located in the high side pressure pipe. to my understanding, this tube is a passive throttling device that flashes our freon into around 25% vapor and 75% liquid mixture, as the freon passes through the evaporator, it attracts the heat from the cabin and basically on the way back to the drier and compressor, the freon gets superheated and flashes back into a vapor mixture which then gets compressed again and yada yada, goes through condensor and subcooling process. also make sure you have the correct amount of PAG compressor oil inside the compressor.

[Avant Nate]

Does the 40 amp condenser fan fuse affect the compressor? The one under the drivers bolster?

[a4kamila6]

Does the 40 amp condenser fan fuse affect the compressor? The one under the drivers bolster?

I think that fuse is only for the aux/compressor fan but worth a check. I wonder if OP's compressor clutch works fine.

[A4INGS]

Update: the compressor will run when directly connected to power. I ran it for 5minutes last night, and unfortunately, no air came out cold.

Last week, I tested the aux fan and found out it was dead. It's now replaced, and didn't make any difference.

What's next to check? What does the control unit check to be functioning before turning the compressor on?

Also, while running last night, I checked the low side gage. Is it normal to do this?

[audinutt]

You are way under charged

Sent from my SM-N900V using Tapatalk

[RENOxDECEPTION]

I would evac and recharge. There's no way to tell how much refrigerant is currently in the system.

You mentioned there was an error from vcds when testing the compressor, what exactly did it say?