2010 JEEP GRAND CHEROKEE lock

ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure, to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type, and tires must be properly inflated, to produce
accurate signals for the computer.
WARNING!
Significant over or under-inflation of tires or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.The ABS conducts a low-speed self-test at about 12 mph
(20 km/h). If you have your foot lightly on the brake
while this test is occurring, you may feel slight pedal
movement. The movement can be more apparent on ice
and snow. This is normal.
The ABS pump motor runs during the self-test at 12 mph
(20 km/h) and during an ABS stop. The pump motor
makes a low humming noise during operation, which is
normal.
WARNING!
•Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to an accident.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need
to slow down or stop.
(Continued)
268 STARTING AND OPERATING

WARNING! (Continued)
•The ABS cannot prevent the natural laws of phys-
ics from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that af-
forded by the condition of the vehicle brakes and
tires or the traction afforded.
•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.
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•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.
•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 the Anti-Lock BrakeSystem (ABS), Traction Control System (TCS), Brake
Assist System (BAS), Electronic Roll Mitigation (ERM),
and Electronic Stability Program (ESP). All five of these
systems work together to enhance vehicle stability and
control in various driving conditions.
Also, your vehicle is equipped with Trailer Sway Control
(TSC) and, if it has four-wheel drive with the NV245
two-speed transfer case, Hill Start Assist (HSA) and Hill
Descent Control (HDC).
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 “Starting and
Operating” for further information.
270 STARTING AND OPERATING

WARNING!
The ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase the
traction afforded by prevailing road conditions. The
ABS cannot prevent accidents, including those re-
sulting 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 jeopardize 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) 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
“Electronic Stability Program (ESP)” in this section for
more information.
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 the
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STARTING AND OPERATING 271

WARNING! (Continued)
•When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age to brakes, axle, engine, transmission, steering,
suspension, chassis structure or tires.
•Safety chains must always be used between your
vehicle and trailer. Always connect the chains to
the hook retainers of the vehicle hitch. Cross the
chains under the trailer tongue and allow enough
slack for turning corners.
•Vehicles with trailers should not be parked on a
grade. When parking, apply the parking brake on
the tow vehicle. Put the tow vehicle transmission
in PARK. For four-wheel drive vehicles, make sure
the transfer case is not in NEUTRAL. Always,
block orchockthe trailer wheels.
(Continued)
WARNING! (Continued)
•GCWR must not be exceeded.
•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
4. Trailer tongue weight rating for the trailer hitch
utilized (This requirement may limit the ability to
always achieve the 10% to 15% range of tongue
weight as a percentage of total trailer weight).
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STARTING AND OPERATING 333

WARNING!
If the driveshaft is removed, the vehicle can roll even
if the transmission is in PARK, which could cause
serious injury or death.
The parking brake must be firmly engaged and the
wheels chocked during driveshaft removal and installa-
tion. The parking brake must remain engaged unless the
vehicle is securely and properly connected to the tow
vehicle, or the driveshaft is completely reinstalled. See
your authorized dealer for proper driveshaft removal
and reinstallation procedures, including flange
orientation/alignment, use of thread-locking compound,
proper bolt torque specifications, etc.
Towing — Quadra-Trac I (Single-Speed Transfer
Case) Four-Wheel Drive Models
Recreational towing is not allowed. This model does not
have a NEUTRAL position in the transfer case.
Towing — Quadra–Trac II /Quadra–DriveII
Four-Wheel Drive Models
CAUTION!
Front or rear wheel lifts should not be used. Internal
damage to the transmission or transfer case will occur
if a front or rear wheel lift is used when recreational
towing.
NOTE: The transfer case must be in the NEUTRAL
position, and the transmission must be in the PARK
position for recreational towing.5
STARTING AND OPERATING 339

HAZARD WARNING FLASHERS
The Hazard Warning flasher switch is located on the
switch bank just above the climate controls.Press the switch to turn on the Hazard Warning
flasher. When the switch is activated, all directional
turn signals will flash on and off to warn oncoming
traffic of an emergency. Press the switch a second time to
turn off the Hazard Warning flasher.
This is an emergency warning system and should not be
used when the vehicle is in motion. Use it when your
vehicle is disabled and is creating a safety hazard for
other motorists.
If it is necessary to leave the vehicle to go for service, the
Hazard Warning flasher will continue to operate with the
ignition key removed and the vehicle locked.
NOTE: With extended use, the Hazard Warning flasher
may run down your battery.
IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce the
potential for overheating by taking the appropriate ac-
tion.
•On the highways — Slow down.
•In city traffic — While stopped, shift the transmission
to NEUTRAL, but do not increase the engine idle
speed.
346 WHAT TO DO IN EMERGENCIES

Spare Tire Stowage
The spare tire is stowed under the rear of the vehicle by
means of a cable winch mechanism. To remove or stow
the spare, use the jack handle to rotate the “spare tire
drive” nut. The nut is located under a plastic cover at the
center-rear of the cargo floor area, just inside the liftgate
opening.
CAUTION!
Do not use power tools to winch the tire up or down.
Impact type tools can damage the winch mechanism.
Spare Tire Removal
Fit the jack handle extension over the drive nut. Use the
lug wrench to rotate the nut counterclockwise until the
spare is on the ground with enough slack in the cable to
allow you to pull the tire out from under the vehicle.
Lowering/Raising Spare Tire
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WHAT TO DO IN EMERGENCIES 349