'99 320e Newly installed A/C compressor blows cold 4 passenger, not for driver :(

Mercedes » E-Class » 1996-2003
Question

My husband recently replaced the A/C Compressor in my 1999 MBZ 320e. Since he finished, the passenger side blows nice and cold. The driver's side? Not at all.
He says that there was something about codes.
Can you tell me if there is a code that we could check or adjust that might address this specific issue? (I live in Arizona. Working A/C is absolutely imperative. Please help!)
Refrigerant Charge is NOT an issue. It was evacuated & weighed in. My husband is a master residential HVAC service technician. He understands the concepts of air conditioning. He knows how to work on car A/C. (He doesnt like to, but he knows how to do it) ... but a Mercedes is a different beast.
Please help.
Thank you.

Please forgive me if I'm duplicating an already asked question. I've been searching for hours, and just found your site. I can't stay awake another second, so thank you in advance for your help and again I'm sorry if I am being redundant.