New owner of 2004 A4 cabriolet and I can't seem to get the "econ" light to go off on climate control. If I push econ button, it goes off, but relights as soon as I release it. Outside temp here is in 50's. Does this mean air conditioning is not working right? Air that comes out is cool, but not cold. Dealer said it is too cold out for air conditioner to work and that is why econ light is on. Any thoughts?