ESP JEEP GRAND CHEROKEE 2009 WK / 3.G Service Manual

WARNING! (Continued)
•The ABS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. 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 jeopardize the user’s safety
or the safety of others.
CAUTION!
The ABS is subject to possible detrimental effects of
electronic interference caused by improperly in-
stalled aftermarket radios or telephones.NOTE:During severe braking conditions, a pulsing
sensation may occur and a clicking noise will be heard.
This is normal, indicating that the ABS is functioning.
•Do not “ride” the brakes by resting your foot on the
pedal. This could overheat the brakes and result in
unpredictable braking action, longer stopping dis-
tances, or brake damage.
•When descending mountains or hills, repeated brak-
ing can cause brake fade with loss of braking control.
Avoid repeated heavy braking by downshifting the
transmission or locking out overdrive whenever pos-
sible.
•Engines may idle at higher speeds during warm-up,
which could cause rear wheels to spin and result in
loss of vehicle control. Be especially careful while
driving on slippery roads, in close-quarter maneuver-
ing, parking, or stopping.
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•Do not drive too fast for road conditions, especially
when roads are wet or slushy. A wedge of water can
build up between the tire tread and the road. This
hydroplaning action can cause loss of traction, braking
ability, and control.
•After going through deep water or a car wash, brakes
may become wet, resulting in decreased performance
and unpredictable braking action. Dry the brakes by
gentle, intermittent pedal action while driving at very
slow speeds.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes ABS (Anti-Lock Brake
System), TCS (Traction Control System), BAS (Brake
Assist System), ERM (Electronic Roll Mitigation), and
ESP (Electronic Stability Program). All five of these
systems work together to enhance vehicle stability and
control in various driving conditions.Also, your vehicle is equipped with TSC (Trailer Sway
Control) and, if it has 4WD with the NV245 two-speed
transfer case, HSA (Hill Start Assist) and HDC (Hill
Descent Control).
ABS (Anti-Lock Brake System)
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.
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WARNING!
ABS (Anti-Lock Brake System) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ABS cannot prevent accidents, in-
cluding 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 an ABS-
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.
TCS (Traction Control System)
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 andstability. 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 ESP are in
either the “Partial Off” or “Full Off” modes. Refer to “ESP
(Electronic Stability Program)” in this section for more
information.
BAS (Brake Assist System)
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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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.
WARNING!
Many factors, such as vehicle loading, road condi-
tions and driving conditions, influence the chance
that wheel lift or rollover may occur. 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 accidents. The capabilities of an
ERM-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.
ESP (Electronic Stability Program)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESP cor-
rects for oversteering or understeering of the vehicle by
applying the brake of the appropriate wheel to assist in
counteracting the oversteer or understeer condition. En-
gine 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.
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•Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The ESP/TCS Indicator Light located in the instrument
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 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!
ESP (Electronic Stability Program) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ESP cannot prevent accidents, in-
cluding 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 an ESP-
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.
The ESP system has three available operating modes in
4WD HIGH range, two available operating modes on
2WD vehicles, and one operating mode in 4WD LOW
range.
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High Range (4WD Models) or 2WD Models
On
This is the normal operating mode for ESP in 4WD HIGH
range and in 2WD vehicles. Whenever the vehicle is
started or the transfer case (if equipped) is shifted from
4WD LOW range or NEUTRAL back to 4WD HIGH
range, the ESP system will be in this “On” mode. This
mode should be used for most driving situations. ESP
should only be turned to “Partial Off” or “Full Off” mode
for specific reasons as noted below.
Partial Off
This mode is entered by momentarily depressing the ESP
OFF switch. When inPartial Offmode, the TCS portion
of ESP, except for the “limited slip” feature described in
the TCS section, has been disabled and the ESP/TCS
Indicator Light will be illuminated. All other stability
features of ESP function normally. This mode is intended
to be used if the vehicle is in deep snow, sand, or gravelconditions and more wheel spin than ESP would nor-
mally allow is required to gain traction. To turn ESP on
again, momentarily depress the ESP OFF switch. This
will restore the normal “ESP On” mode of operation.
ESP OFF Switch
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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 ESP OFF switch. Once the situation
requiring ESP to be switched to the “Partial Off” mode is
overcome, turn ESP back on by momentarily depressing
the ESP OFF switch. This may be done while the vehicle
is in motion.
Full Off (4WD Models Only)
This mode is intended for off-highway or off-road use
when ESP stability features could inhibit vehicle maneu-
verability due to trail conditions. This mode is entered by
depressing and holding the ESP OFF switch for five
seconds when the vehicle is stopped and the engine is
running. After five seconds, the ESP/TCS Indicator Light
will illuminate, and the “ESP OFF” message will appear
in the Electronic Vehicle Information Center (EVIC).
Refer to “Electronic Vehicle Information Center (EVIC)”
in Section 4 of this manual for more information.In this mode, ESP and TCS, except for the “limited slip”
feature described in the TCS section, are turned off until
the vehicle reaches a speed of 40 mph (64 km/h). At
40 mph (64 km/h), the system returns to “Partial Off”
mode, described above. When the vehicle speed drops
below 35 mph (56 km/h), the ESP system shuts off. ESP
is deactivated at low vehicle speeds so that it will not
interfere with off-road driving, but ESP function returns
to provide the stability feature at speeds above 40 mph
(64 km/h). The ESP/TCS Indicator Light will always be
illuminated when ESP is off. To turn ESP on again,
momentarily depress the ESP OFF switch. This will
restore the normal “ESP On” mode of operation.
NOTE:The “ESP OFF” message will display, and the
audible chime will sound, when the shift lever is placed
in the PARK position from any other position, and then
moved out of the PARK position. This will occur even if
the message was previously cleared.
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WARNING!
With the ESP switched off, the enhanced vehicle
stability offered by ESP and ERM are unavailable. In
an emergency evasive maneuver, the ESP and ERM
systems will not engage to assist in maintaining
stability. The “Full Off” ESP mode is intended for
off-road use only.
4WD Low Range
Full Off
This is the normal operating mode for ESP 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
ESP system will be in this “Full Off” mode. In 4WD LOW
range, ESP and TCS, except for the “limited slip” feature
described in the TCS section, are turned off until the
vehicle reaches a speed of 40 mph (64 km/h). At 40 mph(64 km/h), the normal ESP stability function returns but
TCS remains off. When the vehicle speed drops below
35 mph (56 km/h), the ESP system shuts off. ESP is
deactivated at low vehicle speeds in 4WD LOW range so
that it will not interfere with off-road driving but ESP
function returns to provide the stability feature at speeds
above 40 mph (64 km/h). The ESP/TCS Indicator Light
will always be illuminated in 4WD LOW range when ESP
is off.
NOTE:The “ESP OFF” message will display, and the
audible chime will sound, when the shift lever is placed
in the PARK position from any other position, and then
moved out of the PARK position. This will occur even if
the message was previously cleared
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WARNING!
With the ESP switched off, the enhanced vehicle
stability offered by ESP and ERM are unavailable. In
an emergency evasive maneuver, the ESP and ERM
systems will not engage to assist in maintaining
stability. The “Full Off” mode is intended for off-
road use only.
TSC (Trailer Sway Control)
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 excessively
swaying 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 andfollow the trailer tongue weight recommendations. Refer
to “Trailer Towing” in Section 5 of this manual. When
TSC is functioning, the ESP/TCS 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 ESP system is in the “Partial Off” or “Full Off”
modes.
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.
HSA (Hill Start Assist) (4WD Models With NV245
Two–Speed Transfer Case Only)
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
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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.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped.
•Vehicle must be on a 8% grade or greater hill.
•Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in REVERSE gear).HSA will work in REVERSE and all forward gears when
the activation criteria have been met. The system will not
activate if the vehicle is placed in NEUTRAL or PARK.
WARNING!
There may be situations on minor hills (i.e., less than
8%), with a loaded vehicle, or while pulling a trailer,
when the system will not activate and slight rolling
may occur. This could cause a collision with another
vehicle or object. Always remember the driver is
responsible for braking the vehicle.
Towing with HSA
HSA will provide assistance when starting on a grade
when pulling a trailer.
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