05 Expy passenger front cold where there should be heat

[dano]

Hey all, while cruising down the highway today, my son tells me that his feet are freezing. Even after adjusting the controls, higher heat and switch to all to the floor, still cold air. Sounds like a blend door, but driver side ok. Thought also something on pass. side not getting vacuum. Any ideas where I should start on this one?
dano

 

[Bedrck47]

if you have the duel zone Automatic Climate Control System I would say the passenger side blend door is you problem