Jeep Grand Cherokee 2013 Owner's Manual page 446

444 UNDERSTANDING YOUR INSTRUMENT PANEL
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
NOTE: In some cases during high temperature trailer
tow operation the Air Conditioning system performance
may be reduced. This is to help protect the engine from
overheating during the high load condition.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months, make
sure the air intake, located directly in front of the wind-
shield, is free of ice, slush, snow, or other obstructions.
Vacation/Storage
Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air
conditioning system at idle for about five minutes in
fresh air with the blower setting in high. This will ensure
adequate system lubrication to minimize the possibility
of compressor damage when the system is started again.