2009 JEEP LIBERTY brakes

WARNING!
The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the ve-
hicle, nor can it increase the traction afforded by
prevailing road conditions. ABS cannot prevent acci-
dents, including those resulting from excessive speed
in turns, driving on very slippery surfaces, 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 reck-
less or dangerous manner, which could jeopardize
the user’s safety or the safety of others.
Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration andstability. A feature of the TCS system functions similar to
a limited slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in the
“Partial Off” mode or the “Full Off” mode. Refer to
“Electronic Stability Program (ESP)” in this section for
more information.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
system detects an emergency braking situation by sens-
ing the rate and amount of brake application and then
applies optimum pressure to the brakes. This can help
reduce braking distances. The BAS complements the
anti-lock brake system (ABS). Applying the brakes very
quickly results in the best BAS assistance. To receive the
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benefit of the system, you must apply continuous brak-
ing pressure during the stopping sequence, (do not
“pump” the brakes). Do not reduce brake pedal pressure
unless braking is no longer desired. Once the brake pedal
is released, the BAS is deactivated.
WARNING!
The Brake Assist System (BAS) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. BAS cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of a BAS-
equipped vehicle must never be exploited in a reck-
less or dangerous manner, which could jeopardize
the user’s safety or the safety of others.
Electronic Roll Mitigation (ERM)
This system anticipates the potential for wheel lift by
monitoring the driver ’s steering wheel input and the
speed of the vehicle. When ERM determines that the rate
of change of the steering wheel angle and vehicle’s speed
are sufficient to potentially cause wheel lift, it then
applies the appropriate brake and may also reduce
engine power to lessen the chance that wheel lift will
occur. ERM will only intervene during very severe or
evasive driving maneuvers. ERM can only reduce the
chance of wheel lift occurring during severe or evasive
driving maneuvers. It cannot prevent wheel lift due to
other factors, such as road conditions, leaving the road-
way, or striking objects or other vehicles.
NOTE:ERM is disabled anytime the ESP is in “Full Off”
mode. Refer to Electronic Stability Program (ESP) for a
complete explanation of the available ESP modes.
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WARNING!
There may be situations where the Hill Start Assist
(HSA) will not activate and slight rolling may occur,
such as on minor hills (i.e., less than 7%), or with a
loaded vehicle, or while pulling a trailer. HSA is not
a substitute for active driving involvement. It is
always the driver ’s responsibility to be attentive to
distance to other vehicles, people, and objects, and
most importantly brake operation to ensure safe
operation of the vehicle under all road conditions.
Your complete attention is always required while
driving to maintain safe control of your vehicle.
Failure to follow these warnings can result in an
accident or serious personal injury.
Towing with HSA
HSA will provide assistance during acceleration on an
incline while towing a trailer.
WARNING!
•If you use a trailer brake controller with your
trailer, the trailer brakes may be activated and
deactivated with the brake switch. If so, there may
not be enough brake pressure to hold both the
vehicle and the trailer on a hill when the brake
pedal is released. In order to avoid rolling down
an incline while resuming acceleration, manually
activate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake pedal.
•HSA is not a parking brake. Always apply the
parking brake fully when leaving your vehicle.
Also, be certain to leave the transmission in PARK.
•Failure to follow these warnings can result in an
accident or serious personal injury.
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Hill Descent Control (HDC) — If Equipped
HDC is only intended for low speed off-road driving.
HDC maintains vehicle speed while descending hills in
off-road driving conditions by applying the brakes when
necessary.
When enabled, HDC senses the terrain and activates
when the vehicle is descending a hill. HDC speed may be
adjusted by the driver to suit the driving conditions. The
speed corresponds to the transmission gear selected.
GearApproximate HDC Set
Speed
1st 1 mph (1.5 km/h)
2nd 3 mph (4.5 km/h)
DRIVE 7.5 mph (12 km/h)
REVERSE 1 mph (1.5 km/h)
NEUTRAL 3 mph (4.5 km/h)
However, the driver can override HDC operation by
applying the brake to slow the vehicle down below the HDC control speed. If more speed is desired during HDC
control, the accelerator pedal will increase vehicle speed
in the usual manner. When either the brake or the
accelerator is released, HDC will control the vehicle at the
original set speed.
NOTE:
HDC is available on vehicles equipped with the
MP1522 transfer case.
•The transfer case must be in 4WD LOW range to
enable HDC.
•HDC is enabled only when the “Hill Descent Control
Indicator Light” in the instrument cluster is on solid.
•HDC will NOT activate when the automatic transmis-
sion is in PARK.
•HDC will NOT activate on level ground.
•HDC will NOT activate at vehicle speeds above
30 mph (50 km/h).
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Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and
rear of your vehicle at the ground can best be determined
by weighing it when it is loaded and ready for operation.The entire vehicle should first be weighed on a commer-
cial scale to ensure that the GVWR has not been ex-
ceeded. The weight on the front and rear of the vehicle
should then be determined separately to be sure that the
load is properly distributed over front and rear axle.
Weighing the vehicle may show that the GAWR of either
the front or rear axles has been exceeded, but the total
load is within the specified GVWR. If so, weight must be
shifted from front to rear, or rear to front, as appropriate
until the specified weight limitations are met. Store the
heavier items down low and be sure that the weight is
distributed equally. Stow all loose items securely before
driving.
Improper weight distributions can have an adverse affect
on the way your vehicle steers and handles, and the way
the brakes operate.
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NOTE:Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options, or authorized dealer-installed
options, must be considered as part of the total load on
your vehicle. Refer to the “Tire and Loading Information”
placard for the maximum combined weight of occupants
and cargo for your vehicle.
Towing Requirements
To promote proper break-in of your new vehicle drive-
train components, the following guidelines are recom-
mended:
CAUTION!
•Avoid towing a trailer for the first 500 miles
(805 km) of vehicle operation. Doing so may dam-
age your vehicle.
•During the first 500 miles (805 km) of trailer
towing, limit your speed to 50 mph (80 km/h).
WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
Make certain that the load is secured in the trailer
and that is will not shift during travel. When traile-
ring cargo that is not fully secured, dynamic load
shifts can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have an accident.
•When hauling cargo, or towing a trailer, do not
overload your vehicle or trailer. Overloading can cause
a loss of control, poor performance, or damage to
brakes, axle, engine, transmission, steering, suspen-
sion, chassis structure, or tires.
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Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to “Tires–General Infor-
mation” in this section for information on tread wear
indicators and for the proper inspection procedure.
When replacing tires, refer to “Tires–General Informa-
tion” in this section for information on replacement
tires and for the proper tire replacement procedures.
Replacing tires with a higher load carrying capacity
will not increase the vehicle’s GVWR and GAWR
limits.
Towing Requirements — Trailer Brakes

Do not interconnect the hydraulic brake system or
vacuum system of your vehicle with that of the trailer.
This could cause inadequate braking and possible
personal injury.
An electronically actuated trailer brake controller is
required when towing a trailer with electronically
actuated brakes. When towing a trailer equipped with
a hydraulic surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers over
1,000 lbs (454 kg) and required for trailers in excess of
2,000 lbs (907 kg).
CAUTION!
If the trailer weighs more than 1,000 lbs (454 kg)
loaded, it should have its own brakes, and they
should be of adequate capacity. Failure to do this
could lead to accelerated brake lining wear, higher
brake pedal effort, and longer stopping distances.
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WARNING!
•Do not connect trailer brakes to your vehicle’s
hydraulic brake lines. It can overload your brake
system and cause it to fail. You might not have
brakes when you need them and could have an
accident.
•Towing any trailer will increase your stopping
distance. When towing you should allow for addi-
tional space between your vehicle and the vehicle
in front of you. Failure to do so could result in an
accident.
Towing Requirements — Trailer Lights And Wiring
Whenever you pull a trailer, regardless of the trailer size,
stoplights and turn signals on the trailer are required for
motoring safety.
The Trailer Tow Package may include a four and seven-
pin wiring harness. Use a factory approved trailer har-
ness and connector.
NOTE:Do not cut or splice wiring into the vehicles
wiring harness.
The electrical connections are all complete to the vehicle
but you must mate the harness to a trailer connector.
Refer to the following illustrations.
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