2008 JEEP GRAND CHEROKEE air conditioning

NOTE:The numbers on the temperature dial represent
a comfort setting when the Mode knob is set to Auto, and
not the actual air temperature.
Operation of the system is quite simple. Begin by turning
the right mode knob to AUTO, and place the blower
control (left knob) to either LO AUTO or HI AUTO. The
LO AUTO position should be used for front seat occu-
pants only. The HI AUTO position should be used when
more air flow is desired, or when rear seat occupants are
present. Dial in the comfort setting you would like the
system to maintain by rotating the driver's or passenger's
control knob. Once the comfort level is selected the
system will maintain that level automatically using the
heating system. Should the desired comfort level require
air conditioning, the system will automatically make the
adjustment.You will experience the greatest efficiency by simply
allowing the system to function automatically. Selecting
the OFF position on the fan control stops the system
completely.
NOTE:The temperature setting can be adjusted at any
time without affecting automatic control operation. How-
ever, if the driver and/or passenger temperature knobs
are set to the full hot or full cold positions, the air
temperature out of the ducts will be full hot or full cold
respectively. With the temperature setting in these posi-
tions, the system does not attempt automatic comfort
control.
230 UNDERSTANDING YOUR INSTRUMENT PANEL

The air conditioning in this system is automatic.
Pressing this button while in AUTO mode will
cause the LED to flash three times and remain off.
This indicates that the system is in AUTO and requesting
the air conditioning is not necessary.
The system will automatically control recircu-
lation. However, pressing this button will tem-
porarily put the system in recirculation mode.
This can be used when outside conditions such
as smoke, odors, dust, or high humidity are present. This
will cause the LED to illuminate.
NOTE:
²The surface of the climate control panel, and the top
center of the instrument panel should be kept free of
debris due to the climate control sensor's location.
Mud on the windshield may also cause poor operation
of this system.
²To provide you with maximum comfort in the auto-
matic mode, during cold start-ups the blower fan will
remain off until the engine warms up. However, the
fan will engage immediately if the defrost mode is
selected or if you manually select a blower speed.
²Under certain conditions (after the vehicle is turned
off) the climate control system may recalibrate and a
noise may be heard for 20 seconds. This is part of
normal operation.
²Most of the time, when in Automatic operation, you
can temporarily put the system into recirculation
mode by pressing the Recirc button. However, under
certain conditions in automatic the system is blowing
air out of the defrost vents. When these conditions are
present and the Recirc button is pressed the indicator
will flash and remain off. This tells you that you are
unable to go into recirculation mode at this time. If you
would like to go to Recirculation mode, you must first
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Air flows through the registers in the back of the
center console, and under the front seats to the rear
seat passengers. These registers can be closed to block
airflow. The center console outlets deliver conditioned
air while the floor outlets deliver heated air.
²Panel
Air flows through the outlets located in the in-
strument panel. Air flows through the registers in
the back of the center console to the rear seat passen-
gers. These registers can be closed to block airflow.
Depress this button to turn on and off the air
conditioning during manual operation only. Con-
ditioned outside air is then directed through the
outlets selected on the mode control dial. The button
includes an LED that illuminates when manual operation
is selected.
NOTE:To manually control the air conditioning the
mode selector must be moved out of the AUTO position.This button can be used to block out smoke,
odors, dust, high humidity, or if rapid cooling
is desired. The recirculation mode should only
be used temporarily. The button includes an
LED that illuminates, which indicates that the recircula-
tion mode is active. You may use this feature separately.
NOTE:Extended use of recirculation may cause the
windows to fog. If the interior of the windows begins to
fog, press the ªRecirculateº icon button to return to
outside air. Some temp./humidity conditions will cause
captured interior air to condense on windows and ham-
per visibility. For this reason, the system will not allow
ªRecirculateº to be selected while in the defrost or
defrost/floor modes. Attempting to use the recirculation
while in these modes will cause the LED in the button to
blink and then turn off.
UNDERSTANDING YOUR INSTRUMENT PANEL 235
4

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 on the Air-conditioning (pressing the snowflake
button) 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 (cigarettesmoke, 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 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 Recommended
Fluids and Genuine Parts for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
N (Neutral) and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.
236 UNDERSTANDING YOUR INSTRUMENT PANEL

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
windshield, is free of ice, slush, snow, or other obstruc-
tions.
Vacation Storage
Anytime you store your vehicle, or keep it out of service
(i.e. vacation) for two weeks or more, run the air condi-
tioning system at idle for about five minutes in the fresh
air and high blower setting. This will insure adequate
system lubrication to minimize the possibility of com-
pressor damage when the system is started again.
UNDERSTANDING YOUR INSTRUMENT PANEL 237
4

Towing Tips Ð Electronic Speed Control (If
Equipped)
þ
Don't use in hilly terrain or with heavy loads.
þWhen using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
þUse speed control in flat terrain and with light loads to
maximize fuel efficiency.
Towing Tips Ð Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
þCity Driving
When stopped for short periods of time, put transmission
in neutral and increase engine idle speed.
þHighway Driving
Reduce speed.
þAir Conditioning
Turn off temporarily.
þrefer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
Recreational towing is not allowed.
296 STARTING AND OPERATING

IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
²On the highways Ð Slow down.
²In city traffic Ð While stopped, put transmission in N
(Neutral), but do not increase engine idle speed.
NOTE:There are steps that you can take to slow down
an impending overheat condition. If your air conditioner
is on, turn it off. The air conditioning system adds heat to
the engine cooling system and turning off the A/C
removes this heat. You can also turn the Temperature
Control to maximum heat, the Mode Control to floor, and
the Fan Control to High. This allows the heater core to act
as a supplement to the radiator and aids in removing heat
from the engine cooling system.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads ªHº,
pull over and stop the vehicle. Idle the vehicle with
the air conditioner turned off until the pointer drops
back into the normal range. If the pointer remains on
the ªHº, and you hear continuous chimes, turn the
engine off immediately, and call for service.
WHAT TO DO IN EMERGENCIES 299
6

CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the
positive post and the negative cable is attached to the
negative post. Battery posts are marked (+) positive
and negative (-) and identified on the battery case.
Also, if a ªfast chargerº is used while battery is in the
vehicle, disconnect both vehicle battery cables before
connecting the charger to battery. Do not use a ªfast
chargerº to provide starting voltage.
Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service shouldinclude cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
WARNING!
²Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi-
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause
the system to fail, requiring costly repairs. Refer
to Section 3 of the Warranty Information Book for
further warranty information.
²The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal
injury or damage to the system, adding refrigerant
or any repair requiring lines to be disconnected
should be done by an experienced repairman.
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