Just to add to the never-ending list of faults, my 2004 A3 now has a failed air-con compressor I thought it was just in need of a re-gas as the car has done 80k+ so probably had a lot of use. Basically wasnt blowing cold. Got a mobile air-con guy out who was really helpful, and he found there was already 410grams of gas in the system (550grams is full), so he took out the gas and did a compression test to see if he could clear any blockages, but was then unable to put any gas back in - so appears a fault with the compressor most likely (as oppose to a fault with the control unit in the car), and obviously no leaks as there was gas in. Anyone got any ideas on the price of a new compressor fitted?... guessing it could be quite expensive?