sometimes my airconditioner will not work on all speeds on 2004 Chevrolet Colorado

sometimes I can start out in the morning and my airconditioner will only work on 4 then later in the day it will also work on 1,2, and 3.Other times it will start out working on all the speeds and then it change it will only work on 4 and then later in the day it will go back to working on all the speeds. My husband says he thinks the switch has gone bad

by in Fort Lauderdale, FL on October 23, 2012
2 answers
ANSWER by , October 23, 2012
poss blower motor resister is going bad its on the outside of your geater box under and near glove box.poss under warranty at dealer o call them 1st with your vin #
ANSWER by , November 06, 2013
Check the ground distribution block. a black box bolted to the right/passenger fender. Sand bolt hole and connection tab lightly to ensure good ground.