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Climate Control Air Flow - 2003 GMC Safari AWD

The climate control air flow selection has suddenly stopped responding and now only blows out the windshield defrost vent - AC still works and blower motor works as well - no longer deflects air to other vents - whats the poss problem??

Probably a disconnected vacuum line.

How do I find it???..looking under the hood I didn’t see any disconnected hoses. Suggestions???

Buy a service manual for your Safari.

You can buy a manual from Helm, or you can pay a small amount for one time or one month or so on of on-line access to it. There are other companies with similar services.

Thanks for the advice!

In 2003 I was on my way out with GM but if they kept any of the design of earlier “M” vans (your body style is called a “m” by GM, or at least it was) the vacuum accumulator tank (where reserve vacuum is stored is located down along one side of the radiator, it is not easily seem or easy to connect hoses too or replace the unit totaly, remember it is mounted down low.

Now there is a vacuum component to the AC control head but these hoses are well secured.

One strange situation of “technican induced failure” was when the inside engine cowl cover is removed and then replaced, it is possible to get the vacuum source hose squished between the engine cover and the body panel, then you have no vacuum for you HVAC system. (the hoses are a little long and can hang down). Has your engine cover been removed and replaced lately? you may want to check this out.

Oldschool - thanks for the reply and advice - haven’t had any work done on vehicle - suddenly just stopped directing airflow - I’m not certain I am even accurately locating the vacuum accumulator,…is it under the washer fluid & antifreeze resivour?? Also,…are the hoses rubber of aluminum?? Thanks for reply.

Rubber hoses with a outside diameter of around 1/4. If you saw it you would know.Not directly under the two items you mention