A6 2002 1.9tdi 130ps - Air Con Failure

**johnnywishbone** · 11-04-2013,02:48 PM

I'm hoping someone can help me with the following problem :-

The "ECON" lamp stays on continuously on my Air-Con control unit and little or no cold air through the vents. After doing a few searches it appeared that this means low gas pressure. I had it re-gassed but still the same, much to my annoyance. It's not as if we have great summer weather in the UK but it would be nice to get it fixed just to stop the wife and kids nagging me during the Summer months !!!

The following report came from the "Cool Tech" equipment doing the re-gassing :-

Recovered R134a - 0.370kg
Recovered Oil - 3ml
Vac Time - 20mins
Leak Test - No Leak Detected

Charged R134a - 0.675kg
Oil Charged - 13ml

It appears to have lost around 50% of the gas and so I thought this would do it but obviously I have another fault. Can anyone offer me some advice please ? Obviously, if it's some sort of pressure switch issue I would appreciate some pointers on location etc.

Cheers,

John.

**Peter D** · 11-04-2013,05:36 PM

Often a failed pressure switch. You need a diagnostic read. Look up a local member on this forum with VCDS to assit you. Regards Peter

**johnnywishbone** · 11-04-2013,07:34 PM

Thanks Peter. I've got VCDS but unfortunately a third party interface cable which fails to access the air con control module for some reason, too many comms fails etc. I'll ask my mate who has the original RossTech lead. Cheers.

**mrnice** · 11-04-2013,08:38 PM

Hi there, I was getting the same message and just managed this successfully with same vcds and ebay cable-
you have to change 'latency' to 2 for the 'port' you're using in horrible ms windows.
no idea what all that means but I googled the problem, followed the
instructions and it works.

**johnnywishbone** · 12-04-2013,10:32 AM

Thanks mrnice I'll give that a go when I get home later.

**johnnywishbone** · 12-04-2013,11:26 AM

mrnice it worked like a dream. I wish I'd seen your reply to my post before ordering another cable......b******s !!!! I just assumed the comms errors were down to a cheap and nasty cable but I followed your instruction, changed the advanced port setting from Latency 16 to 2 and worked perfectly.

Now then, here's the faults it threw up :-

00819 - High Pressure Sensor G65
01592 - Air Quality Sensor G238

Any ideas on the locations of the sensors etc ??

Cheers,

John.

**mrnice** · 12-04-2013,01:04 PM

The air quality sensor sits just in front of the cabin filter below windscreen cowl.
i think it its function is to do with air re circulation mode for the climate control.
i had this code too and decided after a bit of google research that i can live without it.

the other one I don't know about,
good luck!

**johnnywishbone** · 12-04-2013,04:28 PM

When you say live without it how do you mean ? Did you just disconnect or short out ? If shorted, which terminals. It looks like I'll have to change the G65 anyway but just called Audi and they wan £74.00 for the G238 !!! Robbbing t***s

Cheers,

John.

**mrnice** · 12-04-2013,08:04 PM

I mean I'm just going to ignore it. As far as Ive gathered its only in use during automatic air re circulation mode which I never use anyhow, it doesn't stop either aircon or heater from working.

**nigel63** · 13-04-2013,11:19 AM

my aircon has packed up,just scanned it and it gives me the code G65,my question is where is this sensor located?
it comes up with the message 0819 high pressure sensor
29-00- short to ground
01592 air quality sensor g238
37-00 faulty.
just as the better weather is coming i thought i would turn on air con coming home from work and it wont come off econ.