the blower speed dial is stuck on 3 and wont work on 1 & 2 on 2004 Pontiac Aztek

started out that the blower ( for heat and a/c) would not work unless it was turned to 3 or above. now the dial broke off and its stuck on 3 so it never shuts off. fixable???

Asked by for the 2004 Pontiac Aztek
a/c heater blower switch assm sounds like its bad but they are pricey. seek diag to make sure b4 spending that kinda money