2009 JEEP GRAND CHEROKEE air condition

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 temperaturecontrol 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.
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4

When using the air conditioner in extremely heavy
traffic, in hot weather, especially when towing a trailer,
additional engine cooling may be required. If this situa-
tion 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 NEUTRAL and depress the accelerator slightly
for fast idle operation to increase coolant flow and fan
speed.
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
obstructions.
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 ensure adequate
system lubrication to minimize the possibility of com-
pressor damage when the system is started again.
272 UNDERSTANDING YOUR INSTRUMENT PANEL

OFF-ROAD DRIVING TIPS
NOTE:Prior to off-road driving, remove the front air
dam to prevent damage. The front air dam is attached to
the lower front fascia with quarter turn fasteners, and can
be removed by hand.
When To Use 4WD LOW Range — If Equipped
When off-road driving, shift to 4WD LOW for additional
traction. This range should be limited to extreme situa-
tions such as deep snow, mud, or sand where additional
low speed pulling power is needed. Vehicle speeds in
excess of 25 mph (40 km/h) should be avoided when in
4WD LOW range.
Driving Through Water
Although your vehicle is capable of driving through
water, there are a number of precautions that must be
considered before entering the water.
CAUTION!
When driving through water, do not exceed 5 mph
(8 km/h). Always check water depth before entering
as a precaution, and check all fluids afterward. Driv-
ing through water may cause damage that may not be
covered by the new vehicle limited warranty.
Driving through water more than a few inches/
centimeters deep will require extra caution to ensure
safety and prevent damage to your vehicle. If you must
drive through water, try to determine the depth and the
bottom condition (and location of any obstacles) prior to
entering. Proceed with caution and maintain a steady
controlled speed less than 5 mph (8 km/h) in deep water
to minimize wave effects.
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CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap (if equipped). This
will prevent moisture and dirt from entering the
valve stem, which could damage it.
Inflation pressures specified on the placard are always
cold tire inflation pressure. Cold tire inflation pressure is
defined as the tire pressure after the vehicle has not been
driven for at least three hours, or driven less than 1 mile
(1.6 km) after a three-hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall.
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build-up, or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
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WARNING!
The limited-use spare tires are for emergency use
only. Installation of this limited-use spare tire affects
vehicle handling. With this tire, do not drive more
than 50 mph (80 km/h). Keep inflated to the cold tire
inflation pressure listed on either your tire placard or
limited-use spare tire and wheel assembly. Replace
(or repair) the original tire at the first opportunity
and reinstall it on your vehicle. Failure to do so could
result in loss of vehicle control.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
WARNING!
Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure some-
one. Do not spin your vehicle’s wheels faster than
35 mph (55 km/h) when you are stuck, and do not let
anyone near a spinning wheel no matter what the
speed.
Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced.
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blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer if the
gasoline contains MMT.
It is even more important to look for gasoline without
MMT in Canada, because MMT can be used at levels
higher than those allowed in the United States.
MMT is prohibited in Federal and California reformu-
lated gasoline.
Materials Added To Fuel
All gasoline sold in the United States is required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normalconditions and would result in additional cost. Therefore,
you should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
•The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance
and damage the emission control system.
•An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your authorized dealer for service assistance.
358 STARTING AND OPERATING

•The use of fuel additives which are now being sold as
octane enhancers is not recommended. Most of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning.
•Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas which can kill.Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the
engine running for an extended period. If the vehicle is
stopped in an open area with the engine running for
more than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.
•Guard against carbon monoxide with proper mainte-
nance. Have the exhaust system inspected every time
the vehicle is raised. Have any abnormal conditions
repaired promptly. Until repaired, drive with all side
windows fully open.
•Keep the liftgate closed when driving your vehicle to
prevent carbon monoxide and other poisonous ex-
haust gases from entering the vehicle.
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Cooling System
To reduce potential for engine and transmission over-
heating, take the following actions:
City Driving
When stopped for short periods of time, shift the trans-
mission into NEUTRAL and increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
SNOW PLOW
Snow plows, winches, and other aftermarket equipment
shouldnotbe added to the front end of your vehicle. The
airbag crash sensors may be affected by the change in the
front end structure. The airbags could deploy unexpect-
edly or could fail to deploy during a collision.
WARNING!
Do not add a snow plow, winches, or any other
aftermarket equipment to the front of your vehicle.
This could adversely affect the functioning of the
airbag system and you could be injured.
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.)
Towing – 2WD Models
Recreational towing is allowed ONLY if the driveshaft
is removed.Towing with the rear wheels on the ground
while the driveshaft is connected can result in severe
transmission damage.
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