Hi:

I have a 2008 Trailblazer, 2WD 4.2L 6 Cyl. All summer my A/C has been working perfectly. Yesterday I was driving, A/C just blowing along, pushing out great cold air as usual. Then it suddenly stopped for about 3 seconds, turned back on blew for a few seconds, turned off again, then back on again... then it went off completely.

Now you can put your hands over the vents and cold air is coming out , it's just not blowing? So, I looked up the fuse locations and the relay locations. I changed all the fuses in both boxes (under the hood and in the box under the seat behind the driver) I tried tapping on the relay to see if it would start up again. It did not. I swapped out the relay for one I was told I could, just to see if that was the culprit, and still no go. It won't blow at any level. Won't do heater either. Blower or something electrical other than fuses?

Other than the Blower motor itself, is there anything else that would cause it to stop blowing? Any help would be very appreciated.

 

I would check to see if there is power going to the blower motor. There could be a bad electrical connection, a burnt connector, or a loose wire. Or, the blower motor control module (used to be called a blower motor resistor pack) could be failing.

Is your HVAC system manual or automatic?

This website might be of benefit to you: https://charm.li/

Good Luck!

 

Is your HVAC system manual or automatic?

It's automatic.

Thank you for the help and the link!!!

 

Good Luck!

Just as an FYI, the automatic HVAC system adds a bit more complexity to the diagnosis, but the service manual should be of help there.