2013 JEEP WRANGLER UNLIMITED Owners Manual

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 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.
CAUTION!The Anti-Lock Brake System is subject to possible
detrimental effects of electronic interference caused by
improperly installed aftermarket radios or telephones. 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.
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.456 STARTING AND OPERATING

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
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
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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 (Continued)458 STARTING AND OPERATING

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% or greater incline (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 (i.e., less than
8%), 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 an-
other vehicle or object. Always remember the driver
is responsible for braking 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.
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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)460 STARTING AND OPERATING

WARNING! (Continued)• 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 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 Infor-
mation Center (EVIC). Refer to “Electronic Vehicle Infor-
mation Center (EVIC)” in “Understanding Your Instru-
ment 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).
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6. Cycle ignition switch OFF then ON.
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 maneu-
vers. 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 (Continued)462 STARTING AND OPERATING