brake JEEP WRANGLER UNLIMITED 2009 Owners Manual

NOTE:If the RKE transmitter is equipped with a screw,
reinstall and tighten the screw until snug.
REMOTE STARTING SYSTEM — IF EQUIPPED
This system uses the Remote Keyless Entry
(RKE) transmitter to start the engine conve-
niently from outside the vehicle while still
maintaining security. The system has a range of
328 ft (100 m).
NOTE: The vehicle must be equipped with an auto-
matic transmission to be equipped with Remote Start.
How to Use Remote Start
All of the following conditions must be met before the
engine will remote start:
•Shift lever in PARK
•Doors closed
•Hood closed
•Hazard switch off
•Brake switch inactive (brake pedal not pressed)
•Ignition key removed from ignition switch
•Battery at an acceptable charge level
•RKE PANIC button not pressed

indicate that the parking brake is applied, that the brake
fluid level is low, or that there is a problem with the
anti-lock brake system reservoir.
If the light remains on when the parking brake has been
disengaged, and the fluid level is at the full mark on the
master cylinder reservoir, it indicates a possible brake
hydraulic system malfunction or that a problem with the
Brake Booster has been detected by the Anti-Lock Brake
System (ABS) / Electronic Stability Program (ESP) sys-
tem. In this case, the light will remain on until the
condition has been corrected. If the problem is related to
the brake booster, the ABS pump will run when applying
the brake and a brake pedal pulsation may be felt during
each stop.
The dual brake system provides a reserve braking capac-
ity in the event of a failure to a portion of the hydraulic
system. A leak in either half of the dual brake system isindicated by the Brake Warning Light, which will turn on
when the brake fluid level in the master cylinder has
dropped below a specified level.
The light will remain on until the cause is corrected.
NOTE:
The light may flash momentarily during sharp
cornering maneuvers, which change fluid level condi-
tions. The vehicle should have service performed, and
the brake fluid level checked.
If brake failure is indicated, immediate repair is neces-
sary.

WARNING!
•Never use the PARK position as a substitute for
the parking brake. Always apply the parking
brake fully when parked to guard against vehicle
movement and possible injury or damage.
•It is dangerous to move the shift lever out of PARK
or NEUTRAL if the engine speed is higher than
the idle speed. If your foot is not firmly on the
brake pedal, the vehicle could accelerate quickly
forward or in reverse. You could lose control of the
vehicle and hit someone or something. Only shift
into gear when the engine is idling normally and
when your right foot is firmly on the brake pedal.
REVERSE
This range is for moving the vehicle backward. Use only
after the vehicle has come to a complete stop. NEUTRAL
This range is used when vehicle is standing for pro-
longed periods with engine running. Engine may be
started in this range. Set the parking brake if you must
leave the vehicle.
NOTE:
Towing, coasting, or driving the vehicle for any
other reason with the shift lever in NEUTRAL can result
in severe transmission damage. Refer to “Recreational
Towing” in Section 5 and “Towing a Disabled Vehicle” in
Section 6 of this manual.
OVERDRIVE
This range is used for most city and highway driving.
The transmission contains an electronically-controlled
fourth gear Overdrive, and will automatically shift from
DRIVE to OVERDRIVE if the following conditions are
present:
•The shift lever is in DRIVE.
286 STARTING AND OPERATING

WARNING!
Always wear your seat belt and firmly tie down
cargo. Unsecured cargo can become projectiles in an
off-road situation.
When to Use 4L (Low) Range
When off-road driving, shift into 4L (Low) for additional
traction and control on slippery or difficult terrain,
ascending or descending steep hills, and to increase low
speed pulling power. This range should be limited to
extreme situations such as deep snow, mud, steep in-
clines, or sand where additional low speed pulling power
is needed. Vehicle speeds in excess of 25 mph (40 km/h)
should be avoided when in 4L (Low) range.
Simultaneous Brake and Throttle Operation
Many off-road driving conditions require the simulta-
neous use of the brake and throttle (two-footed driving).
When climbing rocks, logs, or other stepped objects,using light brake pressure with light throttle will keep the
vehicle from jerking or lurching. This technique is also
used when you need to stop and restart a vehicle on a
steep incline.
Driving In Snow, Mud and Sand
Snow
In heavy snow or for additional control and traction at
slower speeds, shift the transmission into a low gear and
the transfer case into 4L (Low) if necessary. Do not shift to
a lower gear than necessary to maintain headway. Over-
revving the engine can spin the wheels and traction will
be lost. If you start to slow to a stop, try turning your
steering wheel no more than a 1/4 turn quickly back and
forth, while still applying throttle. This will allow the
tires to get a fresh
biteand help maintain your momen-
tum.
300 STARTING AND OPERATING

CAUTION!
Reduced tire pressures may cause tire unseating and
total loss of air pressure. To reduce the risk of tire
unseating, while at a reduced tire pressure, reduce
your speed and avoid sharp turns or abrupt maneu-
vers.
Crossing Obstacles (Rocks and Other High
Points)
While driving off-road, you will encounter many types of
terrain. These varying types of terrain bring different
types of obstacles. Before proceeding, review the path
ahead to determine the correct approach and your ability
to safely recover the vehicle if something goes wrong.
Keeping a firm grip on the steering wheel, bring the
vehicle to a complete stop and then inch the vehicleforward until it makes contact with the object. Apply the
throttle lightly while holding a light brake pressure and
ease the vehicle up and over the object.

Driving Downhill
Before driving down a steep hill, you need to determine
if it is too steep for a safe descent. What is the surface
traction? Is the grade too steep to maintain a slow,
controlled descent? Are there obstacles? Is it a straight
descent? Is there plenty of distance at the base of the hill
to regain control if the vehicle descends to fast? If you feel
confident in your ability to proceed, then make sure you
are in 4L (Low) and proceed with caution. Allow engine
braking to control the descent and apply your brakes, if
necessary, but do not allow the tires to lock.

After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is
always a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
•After extended operation in mud, sand, water, or
similar dirty conditions, have the radiator, brake ro-
tors, wheels, brake linings, and axle yokes inspected
and cleaned as soon as possible.

WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also, be certain to leave an automatic
transmission in PARK, a manual transmission in
REVERSE or 1st gear. Failure to do so may allow
the vehicle to roll and cause damage or injury.
•Never leave children alone in a vehicle. Leaving
unattended children in a vehicle is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Do not leave the key in
the ignition. A child could operate power win-
dows, other controls, or move the vehicle.
When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade. The parking brake should always be applied whenever
the driver is not in the vehicle.
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.

benefit of the system, you must apply continuous brak-
ing pressure during the stopping sequence. Do not
reduce brake pedal pressure unless braking is no longer
desired. Once the brake pedal is released, the BAS is
deactivated.

speed of the vehicle. When ERM determines that the rate
of change of the steering wheel angle and vehicle’s speed
are sufficient to potentially cause wheel lift, it applies the
appropriate brake and may reduce engine power to
lessen the chance that wheel lift will occur. ERM will only
intervene during very severe or evasive driving maneu-
vers.
Electronic Roll Mitigation (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 road-
way or striking objects or other vehicles.
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.