Climate control stuck in defrost

CAL SCHAPPELL

MEMBER
1994 CHEVROLET CORVETTE
5.7L
V8
2WD
MANUAL
96,000 MILES

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.

Thursday, September 19th, 2019 AT 8:48 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

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

Image (Click to make bigger)