Blower Motor works sometime on 2006 Chevrolet Colorado

My heater/AC fan will work all the time in high speed. All other speeds will not work sometimes. Have you an idea what’s wrong with this?

by in Batavia, NY on July 22, 2012
3 answers 2 comments
ANSWER by , July 22, 2012
system electrical diagram and circuit description of operation......then you can guess all you want or diagnose it with the correct info & troubleshooting guide.
ANSWER by , July 22, 2012
BLOWER RESISTOR! High speed is not controlled by the resistor,but the lower speeds are. Located near the blower motor behind glove box.
COMMENT by , July 23, 2012
This is very helpful. Is the resistor in the cab or on the firewall?
COMMENT by , July 23, 2012
LOOK BEHIND GLOVE COMPARTMENT!! Maybe you should seek a mechanic's help. GOOD LUCK.
ANSWER by , July 23, 2012
ck blower motor resistor it defaults to high if its bad most of the time