No air from defrost vent

[LJDC]

It’s cold where I am, so I have the heat on. Yesterday I tried to defrost the windshield, and I discovered that there’s no air coming from the vent below the windshield. No matter which setting I choose, the air only blows from the dash vents.

Is this common? Is there an easy fix

 

[Gilaguy23]

Most vehicles will default to defrost if the system fails as a safety item. Guess didnt get the memo. I digress.....check all the spaghetti tubes for breaks/vac leaks.

 

[KennethS]

Is this common? Is there an easy fix

Yes and yes. As noted above, loss of vacuum causes the vents to default to the floor / heater. This many times results from a detached vacuum hose at either the intake manifold or the vacuum reservoir.

 

[LJDC]

Yes and yes. As noted above, loss of vacuum causes the vents to default to the floor / heater. This many times results from a detached vacuum hose at either the intake manifold or the vacuum reservoir.

It sounds like I should check two places for disconnected vacuum hoses: (1) in the engine compartment, and (2) in the dash. Is that right?

 

[Rygrego]

On my 02 it was below my battery tray at the vacuum reservoir.