PDA

View Full Version : Please Help A4 B6 2004 AC stopped working! Help I'm baking here!



AyyFourBoy
13-08-2024, 07:12 PM
Hi All,
So its 30 DegC outside, so no surprise the AC has packed in!

My wife took it to be re-gassed, but the chap told her the compressor's not working.
I've looked up test software values in my manual, and checked them with VCDS Lite, and they are all within good operating limits!

Readings:-
N280 Current:- 0.65A (0.3-0.65 good, although high)
N280 Duty cycle:- 65% (30-100% good)
G65 Pressure sender:- 25% (12-88% good)
Fridge pressure:- 7.0Bar (2.6-29 good)

What doesn't seem right is that the fridge circuit pressure doesn't change with the engine revs, just stays at 7.0 dead.
Would this suggest the pressure sensor's dead?
Or maybe confirming the compressor's doing nothing?

The vent flaps all seem to be controlling ok.

Other readings:-
Compressor torque:- 0
Required torque:- 5Nm

Which suggests to me that the compressors not being driven(?)

But as far as I can work out, this compressor doesn't have a controlled clutch, so how can that be?
The belt is fine, the only slightly odd thing is the plastic cover on the compressor pulley is not sitting flat, its dished out on one side.

Do compressors just die? Is the clutch/pulley busted?
(Coming up for 200k miles!)

Any help hugely appreciated!!

Thanks
Paul

Crasher
14-08-2024, 01:26 PM
Constant drive modulated delivery compressor and problem Sanden, bloody useless and always failing. The key point is no codes, no chill, new compressor and we only fit Denso.