Originally Posted by obewan 
You are correct that you can test it with 12 volts. No water involved at all. It should pass air when cold and when the 12 volts is applied it will close over time, at that point is should no longer pass any air through. The ECU knows nothing about what this valve is doing. It is used to give the really fast idle when the car is cold.
Symptom of failure is car needs throttle open to start when cold, then will die if you don't keep the throttle open. After maybe a minute or 2 it will run ok. This is not the time of year when it should give you much problem though. They usually fail such that is is stuck closed.
I stand corrected. I will need to open the FSM again and see how it operates. I was always under the impression that it's controlled only by heat, and not by voltage. I figured it was obvious that it would operate that way, because it sits directly on top of a coolant passage on the lowport. If you look at the lowport intake, two coolant hoses connect directly underneath the AAC, which makes me think that it's being effected by heat alone, and not by anything else. The voltage drop (resistance) would then allow the ECU to determine the AAC percentage based on this, and enrichen the mixture, or lean it.
Then again, the CLT does the same thing, so I guess that wouldn't make sense. Meh now I have to read again
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