When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My experience is with the dual zone a/c units. No codes and cool on passenger side but not the driver side equals low on refridgerant. Bad actuators will have the same symptons but will make a HVAC code appear on the DIC.
I believe, maybe someone else will confirm, that the systems that are not dual zone don't have those actuators. That is what you mean by manual (3 dials) isn't it, not dual zone.