OKAY MOTOR HVAC Heater Control Valve for 2006-2011 Audi A6 S6 A6 Quattro HVAC Heater Control Valve Unit for 05-11 A6 S6 A6 Quattro 3.0L 3.1L 3.2L 4.2L 5.2L Part number: 4F1959617B ; 4F1-959-617; 4F1-959-617-A; 4F1959617; 4F1959617A New Aftermarket Replacement Unit. 180-days Manufacturer Type Warranty Limited. Applications: A6 S6 A6 Quattro; Common cure for intermittent heat with the A/C on