2011 JEEP WRANGLER brakes

always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•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 the radiator, fan, 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 a collision. 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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ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer 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.
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.
WARNING!
•Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to a collision.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need
to slow down or stop.
(Continued)
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WARNING! (Continued)
•The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can they increase braking or steering
efficiency beyond that afforded by the condition
of the vehicle brakes and tires or the traction
afforded.
•The ABS cannot prevent collisions, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing.
•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.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Hill Start Assist (HSA), Electronic Roll
Mitigation (ERM), Electronic Stability Control (ESC),
Trailer Sway Control (TSC), and Hill Descent Control
(HDC). All of these systems work together to enhance
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vehicle stability and control in various driving condi-
tions, and are commonly referred to as ESC.
WARNING!
The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the ve-
hicle, nor can they increase the traction afforded by
prevailing road conditions. The ABS cannot prevent
collisions, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. 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.
Traction Control System (TCS)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brakepressure is applied to the slipping wheel(s) to provide
enhanced acceleration and stability. 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 ESC are in either the “Partial Off” or “Full Off”
modes. Refer to “Electronic Stability Control (ESC)” in
this section for further 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
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HSA On Automatic Transmission Vehicles
The system will work in REVERSE, and all forward gears
on vehicles equipped with an automatic transmission.
The system will not activate if the vehicle is placed in
NEUTRAL.
HSA On Manual Transmission Vehicles
The system will work in REVERSE, forward gears, and
NEUTRAL on manual transmission equipped vehicles.
The system does not recognize NEUTRAL on manual
vehicles, thus it will hold the vehicle on an incline for a
short period while in NEUTRAL, regardless of clutch
position. To prevent this, do not attempt to roll down a
hill simply by putting the transmission in NEUTRAL and
letting gravity act on the vehicle, as the HSA will prevent
the vehicle from rolling. Instead, use the appropriate gear
for moving in the desired direction.
Towing With HSA
HSA will provide assistance when starting on a grade
when pulling a trailer.
WARNING!
•If you use a trailer brake controller with your
trailer, your trailer brakes may be activated and
deactivated with the brake switch. If so, when the
brake pedal is released there may not be enough
brake pressure to hold the vehicle and trailer on a
hill and this could cause a collision with another
vehicle or object behind you. In order to avoid
rolling down the hill while resuming acceleration,
manually activate the trailer brake prior to releas-
ing the brake pedal. Always remember the driver
is responsible for braking the vehicle.(Continued)
414 STARTING AND OPERATING

swaying trailer is recognized. No driver action is re-
quired. Note that TSC cannot stop all trailers from
swaying. Always use caution when towing a trailer and
follow the tongue weight recommendations. Refer to
“Trailer Towing” in “Starting and Operating” for further
information. When TSC is functioning, the “ESC
Activation/Malfunction Indicator Light” will flash, the
engine power may be reduced and you may feel the
brakes being applied to individual wheels to attempt to
stop the trailer from swaying. TSC is disabled when the
ESP system is in the “Partial Off” or “Full Off” modes.
WARNING!
If TSC activates while driving, slow the vehicle
down, stop at the nearest safe location, and adjust the
trailer load to eliminate trailer sway.
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.The symbol indicates the status of the Hill
Descent Control (HDC) feature. The lamp will
be on solid when HDC is armed. HDC can only
be armed when the transfer case is in the “4WD
LOW” position and the vehicle speed is less then 30 mph
(48 km/h). If these conditions are not met while attempt-
ing to use the HDC feature, the HDC indicator light will
flash on/off.
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.
424 STARTING AND OPERATING

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.CAUTION!
Do not load your vehicle any heavier than the GVWR
or the maximum front and rear GAWR. If you do,
parts on your vehicle can break, or it can change the
way your vehicle handles. This could cause you to
lose control. Also, overloading can shorten the life of
your vehicle.
TRAILER TOWING
In this section, you will find safety tips and information
on limits to the type of towing you can reasonably do
with your vehicle. Before towing a trailer, carefully
review this information to tow your load as efficiently
and safely as possible.
To maintain warranty coverage, follow the requirements
and recommendations in this Owner’s Manual concern-
ing vehicles used for trailer towing.
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WARNING! (Continued)
•Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
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 a collision.
•When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age to the brakes, axle, engine, transmission, steer-
ing, suspension, chassis structure or tires.
•Safety chains must always be used between your
vehicle and trailer. Always connect the chains to
the frame or hook retainers of the vehicle hitch.
Cross the chains under the trailer tongue and
allow enough slack for turning corners.(Continued)
WARNING! (Continued)
•Vehicles with trailers should not be parked on a
grade. When parking, apply the parking brake on
the tow vehicle. Put the tow vehicle automatic
transmission in PARK. With a manual transmis-
sion, shift the transmission into first gear. And
with four-wheel-drive vehicles, make sure the
transfer case is not in N (Neutral). Always, block
orchock the trailer wheels.
•GCWR must not be exceeded.
•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
(Continued)
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