2008 JEEP GRAND CHEROKEE Owners Manual

In this mode, ESP and TCS, except for the ªlimited slipº
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 ªPartial Offº mode,
described above. When the vehicle speed drops below 35
mph (56 km/h) the ESP system shuts off. ESP is deacti-
vated 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 ªESP/TCS Indicator Lightº will always be illumi-
nated when ESP is off. To turn ESP on again, momen-
tarily depress the ªESP OFFº switch. This will restore the
normal ªESP Onº mode of operation.
NOTE:The ªESP OFFº message will display and the
audible chime will sound when the gear selector is
placed into the ªPº (Park) position from any other
position, and then moved out of the ªPº (Park) position.
This will occur even if the message was previously
cleared.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 ªFull Offº 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 ªFull Offº mode. In 4WD low range, ESP
and TCS, except for the ªlimited slipº feature described
in the TCS section, are turned off until the vehicle reaches
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 145
3

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). The9ESP/TCS Indicator Light9will always be
illuminated in 4WD low range when ESP is off.
NOTE:The ªESP OFFº message will display and the
audible chime will sound when the gear selector is
placed into the ªPº (Park) position from any other
position, and then moved out of the ªPº (Park) position.
This will occur even if the message was previously
clearedWARNING!
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 ªFull Offº 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
146 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

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
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
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:
²Vehicle must be stopped.
²Vehicle must be on a 8% grade or greater hill.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 147
3

²Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in R (Reverse) gear).
HSA will work in R (Reverse) and all forward gears when
the activation criteria have been met. The system will not
activate if the vehicle is placed in N (Neutral) or P (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.
WARNING!
²If 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 accelera-
tion, manually activate the trailer brake prior to
releasing the brake pedal. Always remember the
driver is responsible for braking the vehicle.
²HSA is not a parking brake. If you stop the
vehicle on a hill without putting the transmission
in P (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.
148 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

HSA Off
If you wish to turn off the HSA system, it can be done
using the Customer Programmable Features in the Elec-
tronic Vehicle Information Center (EVIC). Refer to ªElec-
tronic Vehicle Information Center (EVIC)º in Section 4 of
this manual.
HDC (Hill Descent Control) (4WD Models with
NV245 Two±Speed Transfer Case Only)
HDC maintains vehicle speed while descending hills
during off-road driving situations and is available in 4
LOW range only. To enable HDC (transfer case must be in
4 LOW range), press the HDC switch. If the HDC switch
is pressed when the vehicle is not in 4 LOW range, the
light in the switch will flash for 5 seconds and HDC will
not be enabled.When HDC is enabled properly, the message ªHILL
DESCENT CONTROLº will appear in the EVIC and the
light in the switch will be illuminated. HDC will auto-
matically apply the brakes to control downhill speed
when necessary. HDC has the capability to sense terrain
Hill Descent Switch
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 149
3

and will only activate when the vehicle is descending a
hill. It will usually not activate on level ground.
The HDC speed may be adjusted by the driver to suit the
driving conditions. The speed corresponds to the trans-
mission gear selected.
²1st = 1 mph (1.6 km/h)
²2nd = 2.5 mph (4 km/h)
²3rd = 4 mph (6 km/h)
²4th = 5.5 mph (9 km/h)
²5th = 7.5 mph (12 km/h)
²Reverse (R) = 1 mph (1.6 km/h)
²Neutral (N) = 2.5 mph (4 km/h)
²Park (P) Ð HDC will not functionHDC also has the capability to sense rough terrain, and
will automatically adjust to a slightly slower set speed
(about.3 mph (.5 km/h) than normal.
HDC operation can be overridden with brake application
to slow the vehicle down below the HDC control speed.
Conversely, if more speed is desired during HDC control,
the accelerator pedal will increase vehicle speed in the
usual manner. When either the brake or the accelerator is
released, HDC will control the vehicle back to the origi-
nal set speed.
HDC is intended for low speed off-road driving only.
At vehicle speeds above 30 mph (48 km/h), HDC will no
longer function. When the vehicle speed drops below 30
mph (48 km/h), HDC function will automatically resume
and the vehicle speed will return to the chosen set speed.
150 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

WARNING!
HDC is only intended to assist the driver in control-
ling vehicle speed when descending hills. The driver
must remain attentive to the driving conditions and
is responsible for maintaining a safe vehicle speed.
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 instrument
cluster 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.
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.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 151
3

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 RUN/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.
152 UNDERSTANDING THE FEATURES OF YOUR VEHICLE