06 chevy 2500 silverado heat only blows warm on one side

2006 Chevy 2500 Silverado heater blows hot on driver’s side and cold on passenger side. None of the controls change the temp. on the pass. side.
Thanks for any help, wife is very cool in the winter.

the blend door actuator for the passenger side is mounted on top of the duct work directly above the driver’s blend door actuator. access to it requires the removal of the glove compartment panel and possibly other dash panels. These little motors fail and usually make a clicking sound when they try to move. You can test it by driving it with 12v from the battery.

Thanks, i’ll give that a try.