Mercedes: A/C, worldpac com, charcoal filter

Question
I have a 1998 Mercedes S420, 106,000 miles, Knoxville TN
A/C has cold air but is not blowing or is blowing very little(as if on low, but fan is set to high)out of the front and the back.  When I set the recirc switch and charcoal filter switch to the on position air seems to come out very slightly more.  All digital readings on the A/C control panel seem to be working fine.  Haven't tried the heater, just the A/C.  Is this possibly the motor and regulator or just one or the other??

Answer
Answer:
Sounds like a bad regulator.

R2022-65372 Blower Regulator Heater : A/C
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