2012 JEEP WRANGLER wheel

When the parking brake is applied with the ignition
switch ON, the “Brake Warning Light” in the instrument
cluster will illuminate.NOTE:
•When the parking brake is applied and the automatic
transmission is placed in gear, the “Brake Warning
Light” will flash. If vehicle speed is detected, a chime
will sound to alert the driver. Fully release the parking
brake before attempting to move the vehicle.
•This light only shows that the parking brake is ap-
plied. It does not show the degree of brake application.
When parking on a hill, it is important to turn the front
wheels toward the curb on a downhill grade and away
from the curb on an uphill grade. For vehicles equipped
with an automatic transmission, apply the parking brake
before placing the shift lever in PARK, otherwise the load
on the transmission locking mechanism may make it
difficult to move the shift lever out of PARK. The parking
brake should always be applied whenever the driver is
not in the vehicle.
Parking Brake
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CAUTION!
If the “Brake Warning Light” remains on with the
parking brake released, a brake system malfunction
is indicated. Have the brake system serviced by an
authorized dealer immediately.
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.
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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
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, brake
pressure 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
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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
quickly results in the best BAS assistance. To receive the
benefit of the system, you must apply continuous brak-
ing pressure during the stopping sequence. Do notreduce 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. The BAS cannot prevent collisions,
including those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. The capabilities 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.
Hill Start Assist (HSA)
The HSA system is designed to assist the driver when
starting a vehicle from a stop on a hill. HSA will maintain
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(manual transmission) with wheels straight. Apply park-
ing brake on manual transmission vehicle.
2. Start the engine.
3. With the engine running, the brake applied, and the
clutch out, rotate the steering wheel 180° counterclock-
wise from center.
4. Press the ESC OFF switch four times within twenty
seconds.
5. Rotate the steering wheel 360° clockwise (180° clock-
wise from center).
6. Cycle ignition switch OFF then ON.
7. If the sequence was completed properly, the “ESC
Activation/Malfunction Indicator Light” will blink sev-
eral times to confirm HSA is off.
Steps 1-7 must be completed within 90 seconds to turn off
HSA. Repeat steps 1-7 to re-enable HSA functionality.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 applies the
appropriate brake and may reduce engine power to lessen
the chance that wheel lift will occur. ERM will only inter-
vene during very severe or evasive driving maneuvers.
Electronic Roll Mitigation (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:Anytime the ESC system is in the “Full Off”
mode, ERM is disabled. Refer to Electronic Stability
Control (ESC) for a complete explanation of the available
ESC modes.
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WARNING!
Many factors, such as vehicle loading, road conditions
and driving conditions, influence the chance that
wheel lift or rollover may occur. Electronic Roll Miti-
gation (ERM) cannot prevent all wheel lift or rollovers,
especially those that involve leaving the roadway or
striking objects or other vehicles. The capabilities of an
ERM-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 Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESC
corrects for over/under steering of the vehicle by apply-
ing the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.ESC uses sensors in the vehicle to determine the vehicle
path intended by the driver and compares it to the actual
path of the vehicle. When the actual path does not match
the intended path, ESC applies the brake of the appro-
priate wheel to assist in counteracting the oversteer or
understeer condition.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The “ESC Activation/Malfunction Indicator Light” (lo-
cated in the instrument cluster), starts to flash as soon as
the tires lose traction and the ESC system becomes active.
The “ESC Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC Activation/
Malfunction Indicator Light” begins to flash during ac-
celeration, ease up on the accelerator and apply as little
throttle as possible. Be sure to adapt your speed and
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WARNING!
Electronic Stability Control (ESC) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESC cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. ESC also cannot prevent accidents resulting
from loss of vehicle control due to inappropriate
driver input for the conditions. Only a safe, attentive,
and skillful driver can prevent accidents. The capa-
bilities of an ESC equipped vehicle must never be
exploited in a reckless or dangerous manner which
could jeopardize the user ’s safety or the safety of
others.The ESC system has three available operating modes in
4H range. The system has one operating mode in 4L
range. Two-wheel drive vehicles and four-wheel drive
vehicles in 2H range have two operating modes.
4H Range (4WD Models) Or 2WD Models
On
This is the normal operating mode for ESC in 4H and
2WD vehicles.
Partial Off
This mode is entered by momentarily pressing the ESC
OFF switch.
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When inPartial Off mode, the TCS portion of ESC has
been disabled and the “ESC Activation/Malfunction
Indicator Light” will be illuminated. All other stability features of ESC function normally. This
mode is intended to be used if the vehicle is in deep
snow, sand, or gravel conditions and more wheel spin
than ESC would normally allow is required to gain
traction. To turn ESC on again, momentarily press the
ESC OFF switch. This will restore the normal “ESC On”
mode of operation.
NOTE:
To improve the vehicle’s traction when driving
with snow chains, or starting off in deep snow, sand, or
gravel, it may be desirable to switch to the “Partial Off”
mode by pressing the ESC OFF switch. Once the situation
requiring ESC to be switched to the “Partial Off” mode is
overcome, turn ESC back on by momentarily pressing the
ESC OFF switch. This may be done while the vehicle is in
motion.
ESC OFF Switch
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