Not sure of the cause of your problem, but I do have a question.

Why would you want to keep the switch on recirculate?  Especially on a long
road trip.  I'd be looking for all the fresh air I could get.

The only time I ever put it on recirculate is cold winter starts when I
start the car and head back into the house to let the car warm up.

thewizkid <kfairris@gmail.com> wrote in news:1177087487.206373.158640
@l77g2000hsb.googlegroups.com:

you failed to mention model year BUT; if 04 classic or earlier then the
controls in the dash are a major design flaw along with the blower
resistor pack (altho the resistor pack will give consistant failures,
speeds will be lost from blower and will not be renewed until part
replaced). the symptoms from a control panel failure are more subtle =
a/c request light will turn off and on at will and recirc function and
lamp will do the same. all probs i have ran into can be remedied by
slapping the hell out of the right side of the console. the problem will
reoccur tho..........replacement part = about $100 + labor if
needed...their is a very easy cleaning process of the circuit board that
gives great results at no cost if you do it yourself...........kjun