2008 JEEP GRAND CHEROKEE SRT Owners Manual

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
benefit of the system, you must applycontinuousbrak-
ing pressure during the stopping sequence (do not
ªpumpº the brakes). Do not reduce brake pedal pressure
unless braking is no longer desired. Once the brake pedal
is released, the BAS is deactivated.WARNING!
BAS (Brake Assist System) cannot prevent the natu-
ral laws of physics from acting on the vehicle, nor can
it increase the traction afforded by prevailing road
conditions. BAS 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 acci-
dents. 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.
136 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

ERM (Electronic Roll Mitigation)
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 vehicles speed
are sufficient to potentially cause wheel lift, it then
applies the appropriate brake and may also reduce
engine power to lessen the chance that wheel lift will
occur. ERM will only intervene during very severe or
evasive driving maneuvers.
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 roadway or striking objects or
other vehicles.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.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 137
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ESP (Electronic Stability Program)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESP cor-
rects for over/under steering of the vehicle by applying
the brake of the appropriate wheel to assist in counter-
acting 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.
²Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
²Understeer - when the vehicle is turning less than
appropriate for the steering wheel position.
The9ESP/TCS Indicator Light9located in the instrument
cluster, starts to flash as soon as the tires lose traction and
the ESP system becomes active. The9ESP/TCS Indicator
Light9also flashes when TCS is active. If the9ESP/TCS
Indicator Light9begins 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.
138 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

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 2 available operating modes.
On
This is the normal operating mode for ESP. Whenever the
vehicle is started, the ESP system will be in this ªOnº
mode. This mode should be used for most driving
situations. ESP should only be turned to ªPartial Offº
mode for specific reasons as noted below.
Partial Off
This mode is entered by momentarily depressing the
9ESP OFFº switch. When in ªPartial Off9mode, the TCS
portion of ESP, except for the ªlimited slipº feature
described in the TCS section, has been disabled and the
9ESP/TCS Indicator Light9will 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 gravel conditions and more wheel spin than ESP
would normally allow is required to gain traction. To
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 139
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turn ESP on again, momentarily depress the9ESP OFFº
switch. This will restore the normal ªESP Onº 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 ªESP PartialOffº mode by pressing the ªESP OFFº switch. Once the
situation requiring ESP to be switched to the ªESP Partial
Offº mode is overcome, turn ESP back on by momen-
tarily depressing the ªESP OFFº switch. This may be
done while the vehicle is in motion.
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 and
follow the tongue weight recommendations. Refer to
ªTrailer Towingº in Section 5 of this manual for more
information on towing a trailer with your vehicle. When
TSC is functioning, the ªESP/TCS Indicator Lightº will
ESP OFF Switch
140 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

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 mode.
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.
ESP/BAS Warning Lamp and ESP/TCS Indicator
Light
The malfunction indicator lamp for the ESP is
combined with the BAS indicator. The yellow
ªESP/BAS Warning Lampº and the yellow
ªESP/TCS Indicator Lightº in the instrumentcluster both come on when the ignition switch is turned
to the ªONº position. They should both go out with the
engine running.
If the ªESP/BAS Warning Lampº comes on
continuously with the engine running, a mal-
function has been detected in either the ESP or
the BAS system, or both. If this light remains on
after several ignition cycles, and the vehicle has been
driven several miles at speeds greater than 30 mph (48
km/h), see your authorized dealer as soon as possible to
have the problem diagnosed and corrected.
NOTE:²9The9ESP/TCS Indicator Light9and the9ESP/BAS
Warning Lamp9come onmomentarilyeach time the
ignition switch is turned ON.
²Each time the ignition is turned ON, the ESP System
will be ON even if it was turned off previously.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 141
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²The ESP Control System will make buzzing or clicking
sounds when it is active. This is normal; the sounds
will stop when ESP becomes inactive following the
maneuver that caused the ESP activation.
REAR PARK ASSIST SYSTEMÐ IF EQUIPPED
The Rear Park Assist System provides visual and audible
indications of the distance between the rear fascia and the
detected obstacle when backing up. Refer to the Warning
Section and Note Section for limitations of this system
and recommendations.
The Rear Park Assist System will remember the last
system state (enabled or disabled) from the last ignition
cycle when the ignition is changed to the ON position.The Rear Park Assist System can be active only when the
shifter is in R (Reverse). If the Rear Park Assist System is
enabled at this shifter position, the system will be active
until the vehicle speed is increased to approximately 11
mph (18 km/h) or above. The system will be active again
if the vehicle speed is decreased to speeds less than
approximately 10 mph (16 km/h).
Rear Park Assist Sensors
The four Rear Park Assist Sensors, located in the rear
fascia, monitor the area behind the vehicle that is within
the sensors' field of view. The monitored area seems oval
in shape.
The sensors can detect obstacles from approximately 11.8
inches (30 cm) up to 59 inches (150 cm) from the rear
fascia in the horizontal direction, depending on the
location and orientation of the obstacle and the type of
obstacle.
142 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

Rear Park Assist Warning Display
The Rear Park Assist Warning Display, located in the
headliner near the flipper glass, provides both visual and
audible warnings to indicate the distance between the
rear fascia and the detected obstacle.When the ignition is changed to the ON position, the
warning display will turn ON all of its LEDs for about 1
second. Each side of the warning display has 6 yellow
and 2 red LEDs. The vehicle is close to the obstacle when
the red LED is ON.
The system dimly illuminates the two outer most yellow
LED's when it is ON and detecting no obstacles. The
following chart shows the warning display operation
when the system is detecting an obstacle:
Rear Park Assist Display
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