brake JEEP COMMANDER 2009 1.G Owner's Guide

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.
•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 brake rotors, wheels,
brake linings, and axle yokes inspected and cleaned as
soon as possible.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might
not have full braking power when you need it to
prevent an accident. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
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WARNING!
Do not use Automatic Transmission Fluid (ATF), or
other types of power steering fluids, when servicing
the power steering system of this vehicle. Damage to
the power steering system can result from the use of
the wrong power steering fluid.
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through an autho-
rized dealer.
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to ensure accurate fluid level reading. Do
not overfill. Use only manufacturers recommended
power steering fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces.
PARKING BRAKE
To set the parking brake, pull the lever up as firmly as
possible. When the parking brake is applied with the
ignition ON, the Brake Warning Light in the instrument
cluster will light. To release the parking brake, pull up
slightly, press the center button, then lower the lever
completely.
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NOTE:The Brake Warning Light indicates only that the
parking brake is applied. It does not indicate the degree
of brake application.
Be sure the parking brake is firmly set when parked and
the shift lever is in the PARK position. When parking on
a hill, you should apply the parking brake before placingthe shift lever in PARK, otherwise the load on the
transmission locking mechanism may make it difficult to
move the shift lever out of PARK.
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 the transmission
in PARK. Failure to do so may allow the vehicle to
roll and cause damage or injury.
•Leaving unattended children in a vehicle is dan-
gerous for a number of reasons. A child or others
could be injured. Children should be warned not
to touch the parking brake or the shift lever. Do
not leave the key in the ignition. A child could
operate power windows, other controls, or move
the vehicle.
(Continued)
Parking Brake
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WARNING! (Continued)
•Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.
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 separatecomputer 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.
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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.
•The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can it increase braking or steering
efficiency beyond that afforded by the condition
of the vehicle brakes and tires or the traction
afforded.
(Continued)
WARNING! (Continued)
•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 Anti-Lock Brake System (ABS) is subject to
possible detrimental effects of electronic interference
caused by improperly installed aftermarket radios or
telephones.
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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.
WARNING!
To use your brakes and accelerator more safely,
follow these tips:
•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.
•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.
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MULTI-DISPLACEMENT SYSTEM (MDS) — 5.7L
ENGINE ONLY
This feature offers improved fuel economy by shutting
off four of the engine’s eight cylinders during light load
and cruise conditions. The system is automatic with no
driver inputs or additional driving skills required.
NOTE:The MDS system may take some time to return
to full functionality after a battery disconnect.
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 “Anti-Lock Brake System” in Section 5 of this
manual.
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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 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 “ESP
(Electronic Stability Program)” in this section for more
information.
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
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benefit of the system, you must applycontinuousbrak-
ing pressure during the stopping sequence (do not
“pump” 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.
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 vehicle 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.
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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.
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.
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.
•Oversteer - when the vehicle is turning more than
appropriate for the steering wheel position.
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