JEEP WRANGLER 2015 JK / 3.G Owners Manual

In the event power assist is lost for any reason (for
example, repeated brake applications with the engine
OFF) the brakes will still function. The effort required to
brake the vehicle will be much greater than that required
with the power system operating.
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.
Anti-Lock Brake System (ABS)
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.
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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.
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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 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.
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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 sen-
sation may occur and a clicking noise will be heard. This
is normal, indicating that the Anti-Lock Brake System is
functioning.
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 Limited Differential
(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
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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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 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. 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
the level of brake pressure the driver applied for a short
period of time after the driver takes their foot off of the
brake pedal. If the driver does not apply the throttle
during this short period of time, the system will release
brake pressure and the vehicle will roll down the hill. The
system will release brake pressure in proportion to
amount of throttle applied as the vehicle starts to move in
the intended direction of travel.
WARNING!
If the clutch pedal (manual transmission only) re-
mains pressed during the application of the throttle,
the HSA will disengage allowing the vehicle to roll
down the incline. This could cause a collision with
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WARNING!(Continued)
another vehicle or object. To avoid this, do not apply
throttle while pressing the clutch pedal until you are
ready to release the clutch. Always remember the
driver is responsible for braking the vehicle.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped
•Vehicle must be on an 8% (approximately) or greater
incline (approximately 3% for manual transmission
equipped vehicles)
•Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in REVERSE gear).
WARNING!
There may be situations on minor hills with a loaded
vehicle, or while pulling a trailer where the system
will not activate and slight rolling may occur, which
could cause a collision with another vehicle or object.
Always remember the driver is responsible for brak-
ing the vehicle.
The system will only work if the intended direction of the
vehicle and vehicle gear match. For example, if the
intended direction is forward up a hill and the vehicle is
in DRIVE (automatic transmission equipped vehicle),
and the activation criteria are met, HSA will activate.
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.
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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. If the vehicle is pointed down hill in NEUTRAL
and your foot is not on the clutch, it will roll down hill,
HSA will not hold you in this case. To prevent this, do not
attempt to roll down a hill simply by putting the trans-
mission in NEUTRAL and letting gravity act on the
vehicle. Instead, use the appropriate gear for moving in
the desired direction.
NOTE:
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.
•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.
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WARNING!(Continued)
•Failure to follow these warnings may cause the
vehicle to roll down the incline and could collide
with another vehicle, object or person, and cause
serious or fatal injury. Always remember to use the
parking brake while parking on a hill and that the
driver is responsible for braking the vehicle.
NOTE:The HSA system may also be turned on and off
if the vehicle is equipped with the Electronic Vehicle
Information Center (EVIC). Refer to “Electronic Vehicle
Information Center (EVIC)” in “Understanding Your
Instrument Panel” for further information.
HSA Off
If you wish to turn off the HSA system, follow this
procedure:
1. Start with the engine off and vehicle in PARK (auto-
matic transmission) or NEUTRAL with clutch out
(manual transmission) with wheels straight. Apply
parking 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.
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7. If the sequence was completed properly, the “ESC
Activation/Malfunction Indicator Light” will blink
several 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 intervene 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.
WARNING!
Many factors, such as vehicle loading, road condi-
tions and driving conditions, influence the chance
that wheel lift or rollover may occur. Electronic Roll
Mitigation (ERM) cannot prevent all wheel lift or
rollovers, especially those that involve leaving the
roadway or striking objects or other vehicles. The
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WARNING!(Continued)
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
driving to the prevailing road conditions.
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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)
ESC On
This is the normal operating mode for ESC in 4H range.
ESC Partial Off
This mode is entered by momentarily pressing the ESC
OFF switch. When in#ESC Partial Off#mode, the TCS
portion of ESC (except for the limited slip feature de-
scribed in the TCS section), has been disabled and the
#ESC Off Indicator Light#will be illuminated.
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