A/C stuck in Defrost?

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Oct 29, 2008
Dallas, Texas
I've got a serious problem.

My A/C is stuck in Defrost.
2002 Ford Taurus, 200,600 miles.
It blows cold, but today when I jumped in it was stuck.

Anyone know how to unstick this one?
I know its on the passengers side front... but where?

Defrost is default in case of a vac leak. The most common vac problem is the fresh/recirc vac line connector in the passenger footwell. Ck to make sure it isn't knocked off.
Something is loose/disconnected in the vacuum control system. It defaults to defrost if something is amiss.

When this happened on my '95 Explorer, it was a vacuum line that became disconnected from the vacuum reservoir (plastic sphere under the hood).
usually 99% of the time stuck in defrost is a vacuum leak.

Start there, was any work done recently, in the underhood area, any accidents/road trash, any interior work done.. such as aftermarket stereo?
Broken vacuum line. The system is designed to default to defrost when there is a lack of vacuum. Find the vacuum manifold and trace the hard line to the firewall and there will be a break in it somewhere.
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