2007 JEEP LIBERTY AC System

AUTOMATIC TRANSMISSION — IF EQUIPPED
CAUTION!
Damage to the transmission may occur if the follow-
ing precautions are not observed:
•Shift into P (Park) only after the vehicle has come
to a complete stop.
•Shift into or out of R (Reverse) only after the
vehicle has come to a complete stop and the
engine is at idle speed.
•Do not shift from R (Reverse), P (Park), or N
(Neutral) into any forward gear when the engine
is above idle speed.
•Before shifting into any gear, make sure your foot
is firmly on the brake pedal.
WARNING!
It is dangerous to shift the selector lever out of P
(Park) or N (Neutral) if the engine speed is higher
than idle speed. If your foot is not firmly on the
brake pedal, the vehicle could accelerate quickly
forward or in reverse. You could lose control of the
vehicle and hit someone or something. Only shift
into gear when the engine is idling normally and
when your foot is firmly on the brake pedal.
Brake/Transmission Interlock System
This system prevents you from moving the gear shift out
of P (Park) and into any gear unless the brake pedal is
pressed. This system is active only while the ignition
switch is in the ON position. Always depress thebrake
pedal first,before moving the gear selector out of P
(Park).
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•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
•After extended operation in mud, sand, water, or
similar dirty conditions, have brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
WARNING!
Abrasive material in any part of the brakes may
cause excessive wear or unpredictable braking. You
might not have full braking power when you need it
to prevent an accident. If you have been operating
your vehicle in dirty conditions, get your brakes
checked and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
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WARNING!
•Always fully apply the parking brake when leaving
your vehicle, or it may roll and cause damage or
injury. Also, be certain to leave an automatic trans-
mission in P (Park), a manual transmission in R
(Reverse) or 1st gear. Failure to do so may allow the
vehicle to roll and cause damage or injury.
•Leaving children in a vehicle unattended is danger-
ous for a number of reasons. A child or others could
be injured. Children should be warned not to touch
the parking brake or the gear selector lever. Don’t
leave the keys in the ignition. A child could operate
power windows, other controls, or move the vehicle.
•Be sure the parking brake is fully disengaged before
driving, failure to do so can lead to brake problems
due to excessive heating of the rear brakes.
When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
ANTI-LOCK BRAKE SYSTEM — IF EQUIPPED
The Anti-Lock Brake System is designed to aid the driver
in maintaining vehicle control under adverse braking
conditions. The system operates with a separate com-
puter to modulate hydraulic pressure to prevent wheel
lock-up and help avoid skidding on slippery surfaces.
All vehicle wheels and tires must be the same size and
type and tires must be properly inflated to produce
accurate signals for the computer.
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WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason, your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test and during an ABS stop to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation, this is normal.During off-road use, loss of traction can temporarily
defeat the system and cause the warning light to illumi-
nate. Turn the ignition OFF and ON again to restore
Anti-Lock Brake System function.
WARNING!
Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to an accident.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
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WARNING!
•Anti-lock system (ABS) cannot prevent the natu-
ral laws of physics from acting on the vehicle, nor
can it increase braking or steering efficiency be-
yond that afforded by the condition of the vehicle
brakes and tires or the traction afforded.
•The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•The capabilities of an ABS equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
CAUTION!
The Anti-Lock Brake System is subject to possible
detrimental effects of electronic interference caused
by improperly installed aftermarket radios or tele-
phones.
NOTE:During severe braking conditions, a pulsing
sensation may occur and a clicking noise will be heard.
This is normal, indicating that the Anti-Lock Brake
System is functioning.
POWER STEERING
The standard power steering system will give you good
vehicle response and increased ease of maneuverability
in tight spaces. The system will provide mechanical
steering capability if power assist is lost.
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If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.
NOTE:Increased noise levels at the end of the steering
wheel travel are considered normal and do not indicate
that there is a problem with the power steering system.
Upon initial start-up in cold weather, the power steering
pump may make noise for a short amount of time. This is
due to the cold, thick fluid in the steering system. This
noise should be considered normal, and does not in any
way damage the steering system.WARNING!
Continued operation with reduced power steering
assist could pose a safety risk to yourself and others.
Service should be obtained as soon as possible.
CAUTION!
Prolonged operation of the steering system at the
end of the steering wheel travel will increase the
steering fluid temperature and it should be avoided
when possible. Damage to the power steering pump
may occur.
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NOTE:The Premium Tire Pressure Monitor System will
automatically locate the pressure values displayed in the
correct vehicle position following a tire rotation.
The suggested rotation method is the “forward-cross”
shown in the following diagram.TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold tire pressure.
The tire pressure will vary with temperature by about 1
psi (7 kPa) for every 12°F (–11°C). This means that when
the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This is defined as the tire
pressure after a vehicle has not been driven for more than
3 hours - and in outside ambient temperature.Refer to
the “Tires – General Information” in this section for
information on how to properly inflate the vehicle’s
tires.The tire pressure will also increase as the vehicle is
driven - this is normal and there should be no adjustment
for this increased pressure.
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The TPM System will warn the driver of a low tire
pressure if the tire pressure falls below the low pressure
warning threshold for any reason, including low tem-
perature effects.
The TPM System will continue to warn the driver of low
tire pressure as long as the condition exists, and will not
turn off until the tire pressure is at or above recom-
mended cold tire pressure. Once the “Tire Pressure
Monitoring Telltale Light” has been illuminated, the tire
pressure must be increased to the recommended cold tire
pressure in order for the “Tire Pressure Monitoring
Telltale Light” to be turned off. The system will automati-
cally update, and the “Tire Pressure Monitoring Telltale
Light” will extinguish once the updated tire pressures
have been received. The vehicle may need to be driven
for up to 10 minutes above 15 mph (24 km/h) to receive
this information.For example, your vehicle has a recommended cold
(parked for more than 3 hours) tire pressure of 33 psi (227
kPa). If the ambient temperature is 68°F (20°C) and the
measured tire pressure is 28 psi (193 kPa), a temperature
drop to 20°F (-7°C) will decrease the tire pressure to
approximately 24 psi (165 kPa). This tire pressure is
sufficiently low enough to turn ON the “Tire Pressure
Monitoring Telltale Light.” Driving the vehicle may cause
the tire pressure to rise to approximately 28 psi (193 kPa),
but the “Tire Pressure Monitoring Telltale Light” will still
be ON. In this situation, the “Tire Pressure Monitoring
Telltale Light” will turn OFF only after the tires have been
inflated to the vehicle’s recommended cold tire pressure
value.
NOTE:Seasonal temperature changes will affect tire
pressure, and the TPM system will monitor the actual tire
pressure in the tire.
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