anikon

Hi

I have a 2006 A6 quattro canadian version and 2 days ago the AC stopped working.

I did some debugging based on the finding on google and here is what's going on:

1. checked the Freon PSI: Low: MAX High: 140
2. the inside blower works, but the air is the ambient temperature
3. the AC compressor doesn't engage.
4. Checked the voltage on the AC compressor plug: 4.95V (i read somewhere that should be 12V)
5. tried to locate the AC clutch relay but i haven't found it. See pictures of the fuse box inside the engine compartment.

This guy says it should be a relay for the AC clutch, but i couldn't find any fuse box to look similar.

justboring: Audi C4 100/A6 Fuse/Relay locations and information

Any suggestions to go from here?

Thanks a lot.



AC compressor voltage: 4.95V




AC PSI




AC pulley




AC clutch fuse box

anikon

I have tested the resistance of the clutch:
Engine stopped: resistance is
12.3 on 200 OHMS scale
0.1 on 2000OHMS scale
0.1 on 20k OHMS scale



Resistance

anikon

I did some more debugging and found the following:

1. Voltage on the compressor with AC ON / OFF: 12.7V / 4.9V
2. The freon PSI: Low: Max, High: 120 PSI

Thanks

anikon

I took the car into a shop and after reading and cleared the faults it started to work again. Most likely the fault 01232 AC compressor regulator valve n280 cause to not engage the compressor.

anikon

The guys at Ultimate Euro Repairs in Davie FL were nice not to charge me anything for clearing the faults.

dennismelvin

Koni Noki

hey im n the same boat zny luc with finding the ac compressor fuse

anikon

In the end I had to replace the indide AC console (the one with all buttons). I took one from PYP (junk yard), replaced it and no other issued so far. The issue that came was that the temperature was not steady, it was fluctuating a lot. Probably one of the ***** was broken.

After replaced, you need to take it to someone with vagcom to match it with you car.

Hope this helps.

MacEwen

I don't think you have a clutch. I believe you have a constant on (variable) compressor. There is a solenoid that activates to change displacement of compressor based on demand. Not sure about Canadian version.

I've been studying this for 3 days now. lol.

I have a 2007 and 2008 A6 3.2L (USA).

I ordered some new G395 pressure sensors today. I hope that helps me get the compressor spinning again. Using VCDS, I could issue a duty cycle to the solenoid, and compressor would run a bit. I think I need the compressor to run, to get the correct amount of refrigerant into the system.

You may have had a bad cabin temperature sensor, which I think is attached to the control panel, behind the tiny vent at the buttons.

David Gao

Hi, Friends,
My Audi Q7 2011 is blowing out air with the same temperature no matter the AC button is on or off. set at "LO" with outside temperature 90F.

The pressure on the low side and high side of the AC pipes are the same, about 125 PSI, no matter the engine is on or off, and the AC button is on or off.

The pipes for R134a on both side have the same temperature as the ambient temperature (90-95F), meaning the compressor is not engaging?

Is the compressor controller/sensor broken? or the cabin temperature sensor telling the AC the the temperature need not to be lowered?

Thank you for any idea.