A/C Blowing HOT and Cold at the Same Time!

I took my '98 Corvette into a Chevy dealer for the following repairs: Replaced the Headlamp Actuator... Found internal short on BCM (warranty company denied claim)... Found brake fluid present @ EBCM and BPMV Replaced
both modules. Manually bled and power bled BPMV... Found underhood connector corroded - Repaired circuit and removed connector... Splice SL 8.695 Parts... Changed Oil.
When they returned the car to me the A/C was blowing HOT (much hotter than outside temperature) out of the center and driver's side vents, and nice and cold out of the passenger side vents. The technitian claimed he didn't touch anything A/C related, but admitted the A/C worked fine the day before when he test drove it.
I remember the same thing happened at another Chevy dealer when they installed a starter. The service writer took it to the back and within five minutes brought it back working fine. He said the A/C just needed to be "reset." Unfortunately this tech didn't have a clue what to do. Anybody have any idea what could be the fix for this?
Thank you,
Steve
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.