Air con faults

[quattromark]

So looking into why my aircon suddenly stopped working - It was around the same time as me discovering a massive amount of water in the passenger footwell......This isn't going to take a genius is it!!

I'd already scanned for faults and got the following>

01592 - Air Quality Sensor (G238)
010 - Open or Short to Plus
Freeze Frame:
Fault Status: 01101010
Fault Priority: 3
Fault Frequency: 1
Reset counter: 231
Mileage: 399109 km
Time Indication: 0
Date: 2005.02.01
Time: 12:31:15


Freeze Frame:
Temperature: 19.0 C


00256 - A/C Pressure/Temperature Sensor (G395)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 3
Fault Frequency: 1
Reset counter: 231
Mileage: 399109 km
Time Indication: 0
Date: 2005.02.01
Time: 12:31:15



For some unknown reason I already had a spare G395 - so stripped down the front of the car and replaced the sensor.

No change - still the same codes.

Checked Pins 1&3 for 12V..all good.
Pin 2 had 12v on it.

Checked to see if I was getting continuity of pin 2 to the climate control unit - very high resistance - traced the cable loom (with the help of diagrams) and found that the 17 pin connector at the bottom of the A pillar had corroded - cleaned this up and now have 1.0 Ohm.

However, AC still not working -

For some reason the control unit is not giving out 12v to the compressor valve (N280) and so not activating it.
If I use VCDS output tests I can activate this valve, so its NOT the wiring at fault here - there is a condition not being met that the climate control unit is expecting.

Moving onto the air quality sensor (G238) - where is this located? - because looking at the diagrams, this is supposed to give a signal to the climate control unit on pin C13......however, this space in the connector is NOT populated!!!

One other point, In MVB on VCDS, it states that the system pressure is 50.0 BAR - It should be 28 BAR maximum - however, it does say system pressure is 50 BAR even with the pressure sensor disconnected.
Usually at this point I would replace the pressure sensor with the original......except I seem to have lost it!!

So does the system think that there is too much pressure in it ( ie faulty sensor)?

And also, I have never had an issue with the AC before this point.

Would be interested to hear views on the possible 'phantom' air quality sensor (G238)

[quattromark]

OK - looked into this a bit further......

My car does NOT have air quality sensor - so don't know why it suddenly thinks it does and its faulty..
And with a new pressure sensor not working, I'm beginning to think that the climate control unit has been damaged (indirectly) by the water leak.