2009 JEEP WRANGLER ESP

together to enhance vehicle stability and control in vari-
ous driving conditions, and are commonly referred to as
ESP.
Anti-Lock Brake System (ABS)
This system aids the driver in maintaining vehicle control
under adverse braking conditions. The system controls
hydraulic brake pressure to prevent wheel lock-up and
help avoid skidding on slippery surfaces during braking.
Refer to “Anti-Lock Brake System” in Section 5 of this
manual for more information about ABS.
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
accidents, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. Only a safe, attentive, and skillful
driver can prevent accidents. The capabilities of an
ABS-equipped vehicle must never be exploited in a
reckless or dangerous manner which could jeopar-
dize 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
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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 ESP are in either the “Partial Off” or “Full Off”
modes. Refer to “ESP (Electronic Stability Program)” in
this section.
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 thebenefit 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 accidents,
including those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of a BAS-
equipped vehicle must never be exploited in a reck-
less or dangerous manner which could jeopardize the
user’s safety or the safety of others.
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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
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)
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•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.
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.
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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, 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 park-
ing brake on manual transmission vehicle.
2. Start the engine.
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3. With the engine running, the brake applied, and the
clutch out, rotate the steering wheel 180° counterclock-
wise from center.
4. Press the ESP 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 “ESP/
TCS 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 thespeed 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 ESP system is in the “Full Off”
mode, ERM is disabled. Refer to ESP (Electronic Stability
Program) for a complete explanation of the available ESP
modes.
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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. Only a
safe, attentive, and skillful driver can prevent acci-
dents. 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 Program (ESP)
This system enhances directional control and stability of
the vehicle under various driving conditions. The ESP
corrects for over/under steering of the vehicle by apply-
ing the brake of the appropriate wheel to assist incounteracting the over/under steer condition. Engine
power may also be reduced to help the vehicle maintain
the desired path.
ESP 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, ESP applies the brake of the appropri-
ate 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 “ESP/TCS Indicator Light” (located in the instru-
ment cluster), starts to flash as soon as the tires lose
traction and the ESP system becomes active. The “ESP/
TCS Indicator Light” also flashes when TCS is active. If
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the “ESP/TCS Indicator Light” begins to flash during
acceleration, 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.
WARNING!
The Electronic Stability Program (ESP) cannot pre-
vent the natural laws of physics from acting on the
vehicle, nor can it increase the traction afforded by
prevailing road conditions. The ESP cannot prevent
accidents, including those resulting from excessive
speed in turns, driving on very slippery surfaces, or
hydroplaning. Only a safe, attentive, and skillful
driver can prevent accidents. The capabilities of an
ESP-equipped vehicle must never be exploited in a
reckless or dangerous manner which could jeopar-
dize the user’s safety or the safety of others.The ESP 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 ESP in 4H and
2WD vehicles. Whenever the vehicle is started or the
transfer case (if equipped) is shifted from 4L range or
NEUTRAL back to 4H range, the ESP system will be in
this mode. This mode should be used for most all driving
situations. The ESP should only be turned to “Partial Off”
or “Full Off” for specific reasons as noted below.
Partial Off
This mode is entered by momentarily pressing the ESP
OFF switch. When in
Partial Offmode, the TCS portion
of ESP has been disabled and the “ESP/TCS Indicator
Light” will be illuminated. All other stability features of
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