Fitment: 2006-2011 Audi A62005-2011 Audi A6 Quattro2008-2012 2014-2015 Audi R82007-2011 Audi S6 Here are some common signs that your vehicle’s blower motor resistor is bad: Loss of HVAC fan control (total or certain speeds) The fan only works on its highest speed setting No air coming from vents Intermittent or inconsistent fan speed .