Jeep 2009 Grand Cherokee - Owner Manual - Manual (Page 273)

captured interior air to condense on windows and ham-
per visibility. For this reason, the system will not allow
“Recirculation” mode to be selected while in the defrost
or defrost/floor modes. Attempting to use Recirculation
while in these modes will cause the LED in the button to
blink and then turn off.
Operating Tips
Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cool
temperatures when it’s rainy or humid. In most cases,
turning the air conditioning (pressing the snowflake
button) on will clear the fog. Adjust the temperature
control, air direction, and blower speed to maintain
comfort.
As the temperature gets colder, it may be necessary to
direct air onto the windshield. Adjust the temperature
control and blower speed to maintain comfort. Higher
blower speeds will reduce fogging. Interior fogging on
the windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant, during the summer, to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Fluids, Lubri-
cants, and Genuine Parts in Section 7 for the proper
coolant type.
UNDERSTANDING YOUR INSTRUMENT PANEL 271
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