Need some advice on Air conditioning diagnosis - Not blowing cold

PlasticMac said:
There is no clutch on the A2 AC compressor, it runs all the time, with flow controlled by the N280. If you turn the AC off, (Econ), the N280 reduces flow to around 5%, but never zero.
Have a read of this, page 59 on. You'll understand it a lot better then.
Mac.
Click to expand...
Sorry, I meant the plastic 'emergency breakout' bit that joins the pully to the compressor drive shaft. This has not failed and the compressor shaft and pully rotate as one. I believe the compressor is OK (and certainly not seized.
 
Hi Mac,

Page 63 describes what I read on the denso website. Basically you could still have a seized compressor and the pulley rotating freely.

EDIT: @Oskar beat me to it.

Evros
 
If the compressor was doing anything, I think you'd see a pressure in Group 001, Block 04, regardless of the N280.
What do you see there?
Mac.
 
As I need to de-gas to fix the issue (from what I can determine), I have ordered the new N280 and will install into a known working comp I already have and swap the whole unit, and regas. Let’s hope that sorts it.
 
Oskar said:
Between 3.6 and 5.2 bar in box 4. Never below 3.6 though.
Click to expand...
That looks OK, the expected range is 2.6 - 29 Bar, (from the label file).
That looks close to the minimum, so could be that the AC thinks it's off, or, as you suspect, The N280 is stuck at the minimum.
Watching with interest, good luck.
Mac.
 
An unexpected but simple resolution.

Firstly, thanks for all the comments and help. It is really appreciated, and sorry for not providing a small but subsequently important aspect.

I was reading the 'Self Study Technology' document kindly provided by @PlasticMac and I noted the presence of the G191 Center Vent Temp sensor. I went looking for this, but still have not found it. However, this made me think it is perhaps part of the hazard light switch in the center vent. Perhaps it is, or perhaps the switch provides power or a connection of some sort. I had my hazard switch disconnected (intended to be re-located) as my iPad mini solution has taken its place.

I reconnected the switch, tucked it away behind the ipad, and all is well with the air con!!!!

I really did not think the hazard light switch would have made any difference, but it seems to.
VCDS as not thrown up any errors for the missing G191 (and research tells me it will, if the sensor has failed), so I am a little confused really, however maybe it has not failed, but for some reason, without the switch or message from the G191, it won't turn on the a/c.

Of course, I tested this the day after booking the air con guy, but that's the way it goes......

I'll post regarding the ipad install at a later date. This has been (and still is) an on-going install, however it will do what I need, in the manner I need it, albeit looking a little untidy.

I was sure it was blowing cold this morning, and perhaps it was, but now it is back to where it was. Perhaps a stuck N280 released once this morning, but it stuck again.
Air con guy is still coming next weekend, so a compressor swap may do it (for either comp or N280). It's on the bench ready to be fitted.

Now I just need some hot weather!

Thanks again,

Matt
 
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@Oskar your ipad install is similar to the Garmin satnav install I did...

1714229951566.jpeg
 
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