defrost only, no vent
 

Troubleshooting steps I have already completed:
Replaced O rings in the module
Self test on the control module - no codes
Control module reset (removed the battery cables, etc.)
Vacuum tested the lines: Failed. even after creating a vacuum on the blue line, I could see and feel that it had no affect.
I was able to reach in and move the vacuum assembly which opened the door.

Any suggestions on what it might be?

thanks