I have a 2001 Chevy Blazer and suddenly the vent control stopped working.
Temperature control works fine, as does fan speed, but all output now comes
through the dash vents, no matter the vent selection made. The normal
pneumatic 'hiss' is there when I try to change the vent setting, but now it
is continuous as opposed to the short duration that is customary as the vent
deflectors change position.
And thank you in advance,