a/c unit sometimes blow air when set to front vents.

2002 GMC ENVOY
240,000 MILES
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GREERMAC
  • MEMBER
  • 1 POST
when set to off, their is a noise(clicking, whining) sound.
There have been times when I don't have the unit on and it still makes
a whining sound. it seems to be coming from the speed cluster section.
when in use, at the max fan speed, the a/c blows no air from the set front vents.
Oct 9, 2011 at 8:50 PM
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RIVERMIKERAT
  • ✓ASE Certified Mechanic
  • 6,110 POSTS
  • ASE Certified Mechanic
Check the relays for the system. Make sure the grounds are solid. When it is set to vent or heater, does the high speed work? If not, Suspect the fan control switch in the dash.
Oct 9, 2011 at 9:17 PM
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