Ask a Mechanic Online and Get Answers to Your Car Questions
There are many technicians from all over the world, who serve any customer of their expertise.
Can I help you today?
I would say there is a jamming flap within the hvac case that is stopping warm air discharge to the face as commanded.
Could be an actuator.
I would take it to Cadillac to see if an actuator is not working, possibly a vacuum leak.
Hope this helps.