Climate control stuck in defrost

1994 CHEVROLET CORVETTE
96,000 MILES • 5.7L • V8 • 2WD • MANUAL
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CAL SCHAPPELL
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  • 1 POST
My electronic climate control is always on defrost and will not change to any other selected function. Even temperature will not change. No lights change it blows out of defroster with compressor engaged on cold fogging windshield. Fan stays on high even after pulling fuses it reverts back immediately.
Sep 19, 2019 at 8:48 PM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Welcome to 2CarPros.

Based on the description, it sounds like you lost engine vacuum to the unit. You will need to check under the dash to see if something is disconnected or damaged as far as a vacuum hose. Also, when checking, start the engine. You may actually be able to hear a hissing from a leak.

I attached a pic below showing the locations of what you need. Also, I placed a star next to the one of most interest and (poorly) wrote temp next to the one that is responsible for changing the air temp entering the vehicle. But, please understand, if this happened at the same time, my first suspect is you lost vacuum from the engine.

Take a look at the picture and let me know what you find,.

Joe
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Sep 20, 2019 at 6:45 PM
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