2009 Jeep Grand Cherokee Owner's Manual - Page 273

UNDERSTANDING YOUR INSTRUMENT PANEL 271 captured interior air to condense on windows and hamper 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, Lubricants, and Genuine Parts in Section 7 for the proper coolant type. 4