I own an '03 A4 V6 FWD Cabriolet. The car isn't driven much in the winter, however today at -20 C, I had to drive it to an appointment and was surprised that the cabin didn't warmed up. I felt warm air coming out of the defroster and cool/cold air coming out at the floor. I read that the issue may be related to faults with the servo motors that activate the various blend doors. I am an intermediate DIY mechanic at best, however, I prefer to complete this repair myself and am hopeful another Audi Forum member may have had a similar experience and can provide advice and/or next steps in addressing this issue with my heat. Thank you.