2008 JEEP GRAND CHEROKEE Owners Manual

To Resume Speed
To resume a previously set speed, push the ªRESUME
ACCELº lever up and release. Resume can be used at any
speed above 25 mph (40 km/h) for 3.7L, 4.7L, and 5.7L
engines, and 14 mph (23 km/h) for 3.0L diesel engines.
To Vary The Speed Setting
When the speed control is ON, speed can be increased by
pushing up and holding ªRESUME ACCELº. Release the
lever when the desired speed is reached, and the new
speed will be set.
Tapping ªRESUME ACCELº once will result ina1mph
(2 km/h) (3.7L, 4.7L, 5.7L, and 3.0L Diesel models) speed
increase. Each time the lever is tapped, speed increases so
that tapping the lever three times will increase speed by
3 mph (5 km/h) (3.7L, 4.7L, 5.7L, and 3.0L Diesel
models).To decrease speed while speed control is ON, push down
and hold ªSET DECELº. Release the lever when the
desired speed is reached, and the new speed will be set.
Tapping the ªSET DECELº button once will result in a 1
mph (2 km/h) speed decrease. Each time the button is
tapped, speed decreases.
NOTE:The Speed Control system has been designed to
shut down if multiple speed control switch functions are
operated simultaneously in order to ensure proper op-
eration. If this occurs, the system can be reactivated by
pushing the speed control switch ON/OFF button and
re-setting the desired vehicle SET speed.
To Accelerate For Passing
Depress the accelerator as you would normally. When the
pedal is released, the vehicle will return to the set speed.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 137
3

Using Speed Control On Hills
The automatic transmission may downshift on hills to
maintain the vehicle set speed.
NOTE:The speed control system maintains speed up
and down hills. A slight speed change on moderate hills
is normal.
On steep hills a greater speed loss or gain may occur so
it may be preferable to drive without speed control.
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 ªAnti-Lock Brake Systemº in Section 5 of this
manual for more information about ABS.
138 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

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 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 ESP are in
either the ªPartial Offº or ªFull Offº modes. Refer to ªESP
(Electronic Stability Program)º in this section for more
information.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 139
3

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.
140 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 brake of the appropriate wheel 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.NOTE:Anytime the ESP system is in the ªFull Offº
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.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 141
3

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.
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.
142 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 3 available operating modes in 4WD
High Range, 2 available operating modes on 2WD ve-
hicles, and 1 operating mode in 4WD Low Range.
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 ªOnº mode. This mode should
be used for most driving situations. ESP should only be
turned to ªPartial Offº or ªFull Offº mode for specific
reasons as noted below.
Partial Off
This mode is entered by momentarily depressing the
9ESP OFFº switch. When in9Partial 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,
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 143
3

or gravel conditions and more wheel spin than ESP
would normally allow is required to gain traction. To
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 ªPartial Offº
mode by pressing the ESP switch. Once the situation
requiring ESP to be switched to the ªPartial Offº mode is
overcome, turn ESP back on by momentarily depressing
the ªESP OFFº 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 ªESP OFFº switch for 5
seconds when the vehicle is stopped and the engine is
running. After 5 seconds, the ªESP/TCS Indicator Lightº
will illuminate, and the9ESP OFF9message will appear in
the Electronic Vehicle Information Center (EVIC). Refer
to ªElectronic Vehicle Information Center (EVIC)º in
Section 4 of this manual for more information.
ESP OFF Switch
144 UNDERSTANDING THE FEATURES OF YOUR VEHICLE