2008 NBS Silverado AC blower fan panting, not working

Gduck24 · July 31, 2013

I have a 2008 NBS crewcab 5.3 4x4 with digital dual climate control.

I recently started having trouble with my ac not working right. Didn't think much of it at first as it was almost like a voltage type issue with the fan blower slowing slightly on occasion under different engine loads. Started getting worse, with a lot of sporadic panting, and now very seldom works correctly, sometimes even not at all. Does not matter if its on auto or manual. Seems like right when you start the truck it works strong and correctly for about 3-4 minutes, then it goes to panting and quits. If I turn it to manual and hit the max fan button it will come back on but not always the strongest level. Levels below 4 seem to pretty much turn the fan off. There is an odd light clicking/clunking that I get back in the dash, could just be an actuator motor. Sometime it sounds like a motor that is getting ticked on and off sometimes too.

I did install a new radio a month ago, AC seemed to work fine directly after. I know some of the older silverados could get messed up with the harnesses that you used on them.

I have installed a new blower control module (resistor). This did not fix it. I know there are at least a couple fairly cheap sensors that are involved, but I am leaning toward it being the actual head control in the dash. What do you guys think?

Watch this video, and turn it up. Any help is appreciated.

[media=560x315]http://www.youtube.com/watch?v=BGymxNl9y2w[/media]

elite0259 · July 31, 2013

did you replace the fan?

NEFisher11 · July 31, 2013

I would also check the fan. I am on my third fan in my truck and it is only a 2011.

Wires · July 31, 2013

Does the '08 still have micro-filters for the air intake? Might be plugged, and the fan is starving for air.

Gduck24 · July 31, 2013

Went and got a new fan at lunch. That's what it was! Cost $100 from autozone, but the install is stupid easy. Two screws to pull the cover and then pull a tab down and twist the motor assembly out. I have had a drill or other motors that have done similar on/off kind of actions but they usually completely die and never come back. This was particularly odd because of the continuous intermittent issues over the last couple weeks. Glad I didn't go chasing sensors.

I would also check the fan. I am on my third fan in my truck and it is only a 2011.

What brand were you getting? Under warranty I assume factory parts? Maybe I'll have better luck with Autozone.

Does the '08 still have micro-filters for the air intake? Might be plugged, and the fan is starving for air.

If they do, I didn't notice it. I had a '99 and an '04 and changed or cleaned those on occasion, which seemed to help some.

NEFisher11 · August 1, 2013

Went and got a new fan at lunch. That's what it was! Cost $100 from autozone, but the install is stupid easy. Two screws to pull the cover and then pull a tab down and twist the motor assembly out. I have had a drill or other motors that have done similar on/off kind of actions but they usually completely die and never come back. This was particularly odd because of the continuous intermittent issues over the last couple weeks. Glad I didn't go chasing sensors.

What brand were you getting? Under warranty I assume factory parts? Maybe I'll have better luck with Autozone.

If they do, I didn't notice it. I had a '99 and an '04 and changed or cleaned those on occasion, which seemed to help some.

Yea all 3 have been under warranty, still ridiculous though how hard is it to make a simple electric motor today??? Hopefully this one last more than 1 year.

Jeff 73 smith · August 12, 2020

I have a 2008 Chevy Silverado replaced resister and fan motor for AC I have digital auto AC controls all settings work with the ac on high the fan will turn on and off at times it doesn't do it all the time seems to do it more at idle then while driving but does do it while driving just not as much put a volt meter at the resister volts go from 13 to 8 when this happens please help me to figure out the fix update I now have replaced the hvac head unit control module in the dash still the same problem tried extra ground to motor still same problem have replaced all fuses relays alternator and battery still same problem any help would be very appreciated

Edited August 23, 2020 by Jeff 73 smith
Still not fixed