Question Asked: 05 Trailblazer. Loud knocking sound under dash
February 01, 2013, 08:45 AM
When Heat turned on in floor or defrost mode, loud knocking from under center of dash. Vent mode is quiet. When I press the re-circ button, it flashes for a second or two, but never turns on... Would this be an accuator? what would I be looking at to fix or have fixed? THANKS!!!