Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
when these work on 4 but not on 1 2 and 3 the issue is a bad blower motor resistor or also the connector what plugs into the resistor
the best action to take is to unplug the blower resistor and see if any of the terminals are melted on the connector or the connector melted if you see any signs of that replace the connector and the resistor
if the connector and terminals are good then just replace the resistor located next to the blower motor
# ***** in this picture is the resistor and # ***** is the connector
did you have any more questions on this concern you are having ?