Hi
I have a A4 1,9 TDI Sline 53 Plate
This also started having issues with the heating and Fans.
Sometimes you could have the fan on full but none of the vents would blow any Air out, The i would turn the Climate totaly off and the fans would stay on. The issue was the Heater Matrix not opening and closing vents.
I have took my car back 3 times for this fault and they coulden,t find anything wrong.
At last ai took it in and they had to replace the AIR CON Compresser and i wiring loom. I have not collected my car yet but ill be intouch when i find out what they have done.
Goo on