No air Hot or cold out of my 97 Dodge B2500 van.?

Question

Repair manuals don't show diagrams of ducting. Checked
Vacuum and electrical.

Answer 1

Eautorepair.net or Alldata.com have online access to factory service manuals for a fee---should show it in there. Check for vacuum leak under the hood in the vacuum line from the engine or vacuum reservoir tank to inside the van.

Answer 2

if your fan is blowing then the door is not opening. It is controlled by vacuum from the controls in your dash. If the fan is not blowing there is a switch located usually behind where the ashtray is. The switch is a small box about 1.5 inches square with a 4 wire plug.