AIRCON EXPERT HELP NEEDED PLEASE

[M9GUK]

So my aircon hasnt worked since i bought the car last year, stuck it into a garage and was told the compressor was knackered. Before i fork out over £600 i thought i would investigate first.

ACCORDING TO VCDS I ONLY HAD 2 BAR OF PRESSURE SO HAD IT TOPPED UP IN A GARAGE AND NOW SAYS 6 BAR

Using VCDS I fired up the car and turned on the climate control on auto and set temp to low. 

ECON IS OFF

VCDS says....

AC VALVE CURRENT (N280) 0.652A      AC VALVE (N280) DUTY CYCLE 60.1%    HIGH PRESSURE SIGNAL (G65) 24.5%   REFRIGERANT PRESSURE 6 BAR

COMPRESSOR SHUT OFF IS 0       LAST SHUT OFF 1       SECOND TO LAST 12     THIRD TO LAST 1

RADIATOR FAN REQUESTED 14.8%       RADIATOR FAN ACTUAL 30%    AIR QUALITY SENSOR  NOT INSTALLED      FRESH/RECIRCULATED AIR REQUEST 40

RADIATOR FAN STARTS UP

With a multimeter i tested the feed to the compressor valve and was getting 9.5v

 

When I turn the ECON on the AC VALVE CURRENT AND THE AC VALVE DUTY CYCLE GOES TO 0

THE CURRENT SHUT OFF CRITERIA CHANGES TO 6

THE RADIATOR FAN REQUESTED AND ACTUAL GOES TO 0

THE REST STAY THE SAME

THE FAN STOPS

VOLTAGE DROPS TO ZERO ON THE FEED TO THE COMPRESSOR VALVE

 

I have a new pressure sensor coming as see that can cause alot of problems, am i right in seeing that this can be changed without draining the system?

Ive watched loads of utube vids and read alot of posts but now a little stuck

Do all these look about right? I thought the ECON was an a/c override but find it strange that things turn off, is this correct?

I would appreciate any help or advice on any obvious problems with these readings or other things to try to diagnose where the fault is.

Many thanks

M9GUK

Edited June 8, 2023 by M9GUK