"Gaetano Pengue" <gaetano.pengue@cae.com> wrote in message
news:bv37jb$5km$1@dns3.cae.ca...
> Why does a car manufacturer force this functionality? The
> salesman said it was made this way so that you get dry warm air. It's so
> cold and dry in the winter here so that argument is not valid, why would
you
> need dryer air?

Believe it or not, the salesman is actually telling the truth. The humidity
comes from your breathing. If your windshield is already clear, then it
probably won't make a difference whether AC is on or off, it can maintain a
clear windshield either way. But try this experiment: while parked in your
driveway (don't do this while driving!), turn off the defrost, and breathe
heavily to fog up the windows real good. Then turn on the defrost (without
AC) and see how long it takes to clear the windshield. Now try the same
experiment again, but turn on the AC. You'll notice that it defogs about
twice as fast with AC.

> I still purchases the car because it had many other features
> but this one still annoys me and gives me the impression they just tried
too
> hard to cut corners.

This point is invalid. It takes more effort to have the AC turn on
automatically with the defrost than to have the driver manually do it. If
they wanted to cut corners, then this "feature" would not exist. Even though
it annoys me, I can understand why the manufacturers (not just Honda) are
all doing this. It's because there's a lot of ignorant drivers out there who
don't understand how to properly defog their window. They've got the fan on
high, but in recirc without AC, wondering why their window keeps fogging up.
The manufacturers do this purely for safety reasons, and it takes them more
effort to do this.

> Anyone know if this irrational functionality could be changed or fixed ?

Yes. Search in this newsgroup in google groups and you'll find the code
sequence. The AC will still turn on when you switch to defrost, but now
you'll be able to turn the AC off.

One way I was able to avoid turning on the AC at all was to switch to
defrost and turn off the AC *before* starting the car. Then after you start
the car, you'll have defrost without AC ever turning on.