Econ light won't switch off - No Air con!


Registered User
Jan 7, 2010
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Hucknall, Nottinghamshire
I have a 2005 A4 which appears to have an air con problem. I have no idea how long it has been like this as I usually leave the ECON button on, but I tried to switch it off the other day and it just wouldn't. Has this happened to anyone else out there, and any ideas what the problem might be? :blackrs4:
Could have lost its gas. I think they're designed to be left on most of the time, to keep the system lubricated. If its not used often enough it can cause problems.
Could be a number of things, re gas, pressure switch, compressor. Needs to be scanned with vcds to pin point exactly.
I have this same problem on my '07 S3 8P.

I did a scan and got the follow error regarding the fan for the interior temp sensor.

Address 08: Auto HVAC Labels: 8P0-820-043.lbl
Part No SW: 8P0 820 043 AD HW: 8P0 820 043 AD
Component: KlimavollautomatH19 0360
Revision: 057901 Serial number: 8P0820043AD
Shop #: WSC 00000 000 00000
VCID: 6ED87AA079B38B68C39

1 Fault Found:
00796 - Fan for Interior Temp Sensor (V42)
011 - Open Circuit - Intermittent
Freeze Frame:
Fault Status: 00101011
Fault Priority: 3
Fault Frequency: 1
Reset counter: 57
Mileage: 44463 km
Time Indication: 0
Date: 2012.09.22
Time: 16:48:55

Freeze Frame:
Voltage: 13.80 V
Temperature: 32.0°C

Cleared it and it hasn't come back. The ECON light still won't go out. There are no other errors shown by VCDS. Is this likely to just be in need of a re-gas? I had a new air-con compressor last summer (2011) as the original had failed. I would've thought it shouldn't need a re-gas until next summer.
low gas or preasure switch