HVAC control module, not working correctly

2003 CHEVROLET ASTRO
220,000 MILES • 6 CYL • 4WD • AUTOMATIC
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BRAXTON123
The control panel has four settings for fan speed low and then two ticks in the middle and then high, all work correctly, except highest speed. When highest speed is selected no air comes out. Tried replacing the panel with a new one having the same problem.
Aug 17, 2025 at 4:28 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,494 POSTS
  • ASE Certified Mechanic
Yep, this happens when the blower resistor assembly goes out, here is the location so you can swap it out and fix the problem. Check out the images (below). Let us know if you need anything else.
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Aug 18, 2025 at 11:14 AM
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