2012 JEEP GRAND CHEROKEE brakes

If you stall or begin to lose forward motionwhile
climbing a steep hill, allow your vehicle to come to a stop
and immediately apply the brakes. Restart the engine,
and shift into REVERSE. Back slowly down the hill,
allowing the compression braking of the engine to help
regulate your speed. If the brakes are required to control
vehicle speed, apply them lightly and avoid locking or
skidding the tires.
WARNING!
If the engine stalls, you lose forward motion, or
cannot make it to the top of a steep hill or grade,
never attempt to turn around. To do so may result in
tipping and rolling the vehicle. Always back care-
fully straight down a hill in REVERSE gear. Never
back down a hill in NEUTRAL using only the brake. Remember, never drive diagonally across a hill always
drive straight up or down.
If the wheels start to slip as you approach the crest of a
hill, ease off the accelerator and maintain forward motion
by turning the front wheels slowly. This may provide a
fresh “bite” into the surface and will usually provide
traction to complete the climb.
Traction Downhill
Shift the transmission into a low gear, and the transfer
case into 4WD LOW range. Let the vehicle go slowly
down the hill with all four wheels turning against engine
compression drag. This will permit you to control the
vehicle speed and direction.
When descending mountains or hills, repeated braking
can cause brake fade with loss of braking control. Avoid
repeated heavy braking by downshifting the transmis-
sion whenever possible.5
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After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
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.
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WARNING!
The ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase the
traction afforded by prevailing road conditions. The
ABS cannot prevent collisions, including those re-
sulting from excessive speed in turns, driving on
very slippery surfaces, or hydroplaning. The capa-
bilities 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, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system, Brake LimitedDifferential (BLD), 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 ESC system is in the “Partial Off” mode.
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
quickly results in the best BAS assistance. To receive the
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benefit of the system, you must applycontinuousbrak-
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 BAS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase the
traction afforded by prevailing road conditions. The
BAS cannot prevent collisions, including those re-
sulting from excessive speed in turns, driving on
very slippery surfaces, or hydroplaning. The capa-
bilities of a BAS-equipped vehicle must never be
exploited in a reckless 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 speed
are sufficient to potentially cause wheel lift, it then
applies the brake of the appropriate wheel 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 roadway or striking objects or
other vehicles.
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Off” mode is overcome, turn ESC back on by momen-
tarily pressing the “ESC OFF” switch. This may be done
while the vehicle is in motion.
4WD Low Range
Partial Off
This is the normal operating mode for ESC in 4WD LOW
range. Whenever the vehicle is started in 4WD LOW
range, or the transfer case (if equipped) is shifted from
4WD HIGH range or NEUTRAL to 4WD LOW range, the
ESC system will be in the “Partial Off” mode.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an exces-
sively swaying trailer and will take the appropriate
actions to attempt to stop the sway. The system may
reduce engine power and apply the brake of the appro-
priate wheel(s) to counteract the sway of the trailer. TSC
will become active automatically once an excessivelyswaying 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 trailer 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
ESC system is in the “Partial Off” mode.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.
470 STARTING AND OPERATING

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)
WARNING! (Continued)
•HSA is not a parking brake. If you stop the vehicle
on a hill without putting the transmission in
PARK and using the parking brake, it will roll
down the hill and could cause a collision with
another vehicle or object. Always remember to use
the parking brake while parking on a hill, and that
the driver is responsible for braking the vehicle.
HSA Off
If you wish to turn off the HSA system, it can be done
using the Customer Programmable Features in the Elec-
tronic Vehicle Information Center (EVIC). Refer to “Elec-
tronic Vehicle Information Center (EVIC)” in “Under-
standing Your Instrument Panel” for further information.
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Ready Alert Braking – If Equipped
Ready Alert Braking may reduce the time required to
reach full braking during emergency braking situations.
It anticipates when an emergency braking situation may
occur by monitoring how fast the throttle is released by
the driver. When the throttle is released very quickly,
Ready Alert Braking applies a small amount of brake
pressure. This brake pressure will not be noticed by the
driver. The brake system uses this brake pressure to allow
a fast brake response if the driver applies the brakes.
Rain Brake Support – If Equipped
Rain Brake Support may improve braking performance
in wet conditions. It will periodically apply a small
amount of brake pressure to remove any water buildup
on the front brake rotors. It only functions when the
windshield wipers are in the LO or HI mode, it does not
function in the intermittent mode. When Rain Brake
Support is active, there is no notification to the driver and
no driver interaction is required.
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Hill Descent Control (HDC) — Four-Wheel Drive
Models With MP3023 Two-Speed Transfer Case
Only
HDC maintains vehicle speed while descending hills
during off-road driving situations and is available in
4WD LOW range only. To enable HDC, press the HDC
switch or put the Selec-Terrain™ system in “ROCK”
mode (“ROCK” mode is only available in 4WD LOW
range).When HDC is enabled, the HDC icon will be illuminated
in the instrument cluster. HDC will automatically apply
the brakes to control downhill speed to the selected level
when necessary on grades greater than approximately
8%. It will usually not activate on level ground.
Hill Descent Switch
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