climate control not working

[conorbhealy]

hi guys and dolls,my 2008 a4 b8 has another problem,during our very brief spell of hot weather here,i tried to switch on my a/c by using the auto button on the control panel,it worked,made all the right noises,increased the blower noise,but i got NO cold air ,have heard since this is a problem with them,pipes crack?has anybody else had this,or any ideas on how to fix,thanks for any help.

[Guest 2]

Are your vents open?

[conorbhealy]

yes,all vents are open and the air coming out is the same temp wether the a/c light is on or off

[slope]

Might need the gas refilled.

[markp306]

There is a fairly common problem (including mine) with the aircon pressure switch. It might me that.

[derekm]

There is a fairly common problem (including mine) with the aircon pressure switch. It might me that.

This happened to mine. Needed new switch and refilled with gas.
It went on a hot day too, I got in turned on AC to max and it started off cold then just got warmer. A few seconds later I could see vapour coming out from under the bonnet. The switch must have failed and the system then lost all its gas.

[conorbhealy]

thanks guys,getting it checked tomorrow,will mention switch to them,let ye know how it goes!

[conorbhealy]

Hi all,just to let you know,got it sorted today,pressure switch had gone (common fault)got it changed and regassed and thankfully its working perfect,
thanks for the info on the switch,it is a very easy change,did it myself,took 5 minutes to change and got an independant mobile guy to re-gas it.

[Leonidas_]

Hi, I have exactly the same problem as you ( the air comes out without cooling )....I just ordered a VCDS diagnostic cable to check for errors ( nothing appears in dashboard )
Can you please share your experience concerning this sensor. where did you purchase it from, part number and were is located to have a look before ordering it? thanks in advanced

[conorbhealy]

hi,the part number for mine was 4HO 959 126,MINE IS THE 2008 B8,it may be a different part number if your car is newer.You cant tell by looking at the part
if its broken,i got a local independent guy to check the system,he said that was the problem,i rang my audi garage,they had part on shelf,(common problem) and changed it myself,got the indy to recheck and regas and it works.If you open your bonnet,see the plastic that goes around the latch and goes between the two headlights,i think 4 star screws hold it in place,remove it and in front of the radiator on the right hand side is the switch/sensor,remove electrical plug,unsrew switch,replace with new one,and then get it regassed,thats what worked for me,but even though this is a common fault,get it diagnoised by aircon specialist first as i was told by my audi garage it could be the generator,hope this helps