Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
I had a very similar concern on a GMC sierra. The ac blower would either stay on after the truck was turned off or the blower would turn on while the truck was sitting in the parking lot and run for who knows how long.
Do you plan to fix this yourself?
If it's the same concern as the sierra I had then it's a fairly easy fix.
Sorry, got pulled away for a sec there.
You'll want to replace the blower motor resistor. In the 2011 model GM calls it the blower control module.
Here is the method for replacing it:
What is probably happening is the module is shorting internally and causing the blower to be powered even though there is no signal from the HVAC control head.
Sometimes the rear AC unit has it's own module, let me check the schematic.
Is the rear blower coming on also? I can't find a schematic from GM that separates them out.
There is a separate resistor for the back unit, but it doesn't indicate the wiring path in the repair manuals.
If both are coming on I would suspect a short in the control head. Do you have a scan tool to look for trouble codes in the HVAC head?
I think your best bet will be to look for codes, then if nothing comes up replace the resistor in the front unit and see if it stops acting up. If it does, and the rear continues to come on by it self then replace it as well. It could be a strange coincidence that both resistors went out at the same time.
I wanted to check and see if you needed any additional help.
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