a/c heater problem

[Pace 1989]

no matter what i put the setting on, the fan only runs through the defroster. heat, a/c, vent, all only blow at the windshield, not through the vent or heater(low).
Any ideas what's wrong?

Ken

 

[Rickracer]

The vacuum supply hose to your heater/AC control is not connected

All the (blend) doors inside the AC/heater housing operate off of vacuum motors/diaphragms, controlled by a rotary vacuum switch. If the vacuum supply is removed, it defaults to defrost.

 

[Pace 1989]

a/c & heater prob

How do I diagnose if it's a switch, or a vacuum line, or what?
Thanks for the response.

Ken

 

[Rickracer]

I'd bet you find the supply hose disconnected