Dual Zone Climate Control stuck in floor and mid.

I just installed an aftermarket blower motor in my 2000 Regal LS (175k miles) with the auto/digital dual zone HVAC. All works fine with the blower motor. But when I hit the air flow button on the main unit. The airflow only vents out of the floor and very faintly from the mid. Regardless of whether I switch from floor, mid or window, airflow still vents out of the floor mostly. I know I need to recharge my ac, but I wouldn't think that that would be the cause of the problem I am having with airflow location. Do I need a new control unit??? Everything else works fine with the ac unit. What gives???

Would really appreciate any input in resolving my issue with the airflow not switching over to the desired locations from my digital HVAC unit. Thank You.

You're correct - The AC charge won't affect the damper positions.

When the selector is changed from defrost to heat to mid position, can you hear the actuators operating? If not, recheck your work to verify all connectors are reinstalled.

There is a procedure for resetting the home positions and linkages. I'll see if I can dig it up.

You're correct - The AC charge won't affect the damper positions. When the selector is changed from defrost to heat to mid position, can you hear the actuators operating? If not, recheck your work to verify all connectors are reinstalled.
There is a procedure for resetting the home positions and linkages. I'll see if I can dig it up.

Thanks for your reply Blue Bowtie. No. I do not hear the actuators operating whenever I attempt in switching airflow over to a desired location, e.g. window, mid, or floor. The selector button for airflow functions properly as the digital display on the HVAC unit shows it displaying correctly. It's just that the airflow remains to be venting out mostly in the floor vents. You mentioned actuators. Where are they located? How many are there? Yes I would appreciate the procedure for resetting the home positions and linkages. Thanks again.

Does the digital dual zone HVAC system in my 00' Regal LS also operate on vacuum lines. If so, where are these lines located. Pics or diagrams would be much appreciated. I'd like to check them for leaks. I'm still having airflow location issues.

See if your black plastic vacuum line is rotted in two- behind the battery- where it goes down to the vacuum reservoir- highly likely on W cars that is where your issue is-- splice in a rubber hose to fix..

Battery gases eat away at the plastic tubing.