Hidden
Features
So
you read the Owner’s Manual cover to cover, and you know it all, right? Well no one really knows how to use all
those radio features, let alone the optional navigation system. But certainly you understand the defroster?
Maybe
not -- Pontiac leaves out a few details.
I’m not sure if Toyota does the same.
If
you’ve read the headlights section, you’ll know that I dislike features where
the car tries to be smarter than the driver, for example the automatic
headlights. That feature was hard to
miss, but the defroster behavior is not as visible. The owner’s manual mentions that the defroster always uses
outside air, regardless of the recirculate switch setting -- sensible enough. So why don’t they mention the A/C? Did you know that anytime the selector is
set to defrost or heat/defrost, the air conditioner is running? The indicator light is not on, but it is
running.
There
are some exceptions. The air
conditioner is on an electrical clutch, so it can be disengaged at inopportune
times. If your foot is to the floor
(throttle 100%) the A/C is disengaged.
It also disengages if the outside air temperature drops below 4C (40F),
if the engine is overheating, or if the engine is revving too slow or too fast.
I
disconnected the switch on my climate control so the A/C is on only when I
explicitly turn it on. You can see how
in the rattles and vibrations / dashboard removal section – look for reference
“E” in the photos, a small connector on the back of the climate control with
yellow and black wires.
What
a difference! The defroster pours out
heat sooner and more prolifically than ever before! But be aware before you do the same, that the defroster will need
some dehumidification assistance from the A/C under certain circumstances! Without the A/C it works fine for routine
solo drives, but in warm wet weather or with wet or numerous passengers the
ventilation is not as good as my old car.
Maybe the price of filtered air is reduced air circulation. I will leave my switch disconnected, because
it is nice to know that on a dry day my A/C is off and I am getting the
best-possible gas mileage. I also don’t
have to deal with fogging caused by the wet A/C coil – the fog that appears on a
cold windshield briefly at startup or as your warm car discovers mid-trip that
the outside air temperature is below 4C.
A perpetually-wet A/C coil can also be a cause of bad odors, since mold
and mildew can thrive in air conditioners.