brakes JEEP WRANGLER 2015 JK / 3.G Owners Manual

Operation of the Brake Warning Light can be checked by
turning the ignition switch from the OFF position to the
ON/RUN position. The light should illuminate for ap-
proximately two seconds. The light should then turn off
unless the parking brake is applied or a brake fault is
detected. If the light does not illuminate, have the light
inspected by an authorized dealer.
The light also will turn on when the parking brake is
applied with the ignition switch in the ON/RUN posi-
tion.
NOTE:This light shows only that the parking brake is
applied. It does not show the degree of brake application.
11. High Beam Indicator
This indicator shows that the high beam head-
lights are on. Push the multifunction control lever
away from you to switch the headlights to high beam.
Pull the lever toward you to switch the headlights back to
low beam. If the driver’s door is open, and the headlights
or park lights are left on, the high beam indicator light
will remain illuminated and a chime will sound.
12. Anti-Lock Brake (ABS) Light
After the ignition is turned on, the Anti-Lock
Brake System (ABS) light illuminates to indicate
function check at vehicle startup. If the light remains on
after startup or comes on and stays on at road speeds, it
may indicate that the ABS has detected a malfunction or
has become inoperative. The system reverts to standard
non-anti-lock brakes.
If both the Brake Warning Light and the ABS Warning
Light are on, see an authorized dealer immediately. Refer
to “Anti-Lock Brake System” in “Starting And
Operating”.
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UNDERSTANDING YOUR INSTRUMENT PANEL 309

Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for both
fuel economy and performance, it should be upshifted as
listed in recommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When heavily
loaded or pulling a trailer these recommended up-shift
speeds may not apply.
Manual Transmission Shift Speeds in MPH (KM/H)
Engine Speeds 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6
3.6LAccel. 15 (24) 24 (39) 34 (55) 47 (76) 56 (90)
Cruise 10 (16) 19 (31) 27 (43) 37 (60) 41 (66)
NOTE:Vehicle speeds shown in the chart above are for
2H and 4H only, vehicle speeds in 4L would be signifi-
cantly less.
Downshifting
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving down
steep hills. In addition, downshifting at the right time
provides better acceleration when you desire to resume
speed. Downshift progressively. Do not skip gears to
avoid overspeeding the engine and clutch.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip, and the vehicle could skid.
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Key Ignition Park Interlock
This vehicle is equipped with a Key Ignition Park Inter-
lock which requires the transmission to be in PARK
before the ignition switch can be turned to the LOCK/
OFF (key removal) position. The key can only be re-
moved from the ignition when the ignition is in the
LOCK/OFF position, and once removed the transmission
is locked in PARK.
NOTE:If a malfunction occurs, the system will trap the
key in the ignition switch to warn you that this safety
feature is inoperable. The engine can be started and
stopped but the key cannot be removed until you obtain
service.
Brake/Transmission Shift Interlock System
This vehicle is equipped with a Brake Transmission Shift
Interlock System (BTSI) that holds the shift lever in PARK
unless the brakes are applied. To shift the transmission
out of PARK, the ignition switch must be turned to the
ON/RUN position (engine running or not) and the brake
pedal must be pressed.
Five-Speed Automatic Transmission — If
Equipped
The transmission gear position display (located in the
instrument cluster) indicates the transmission gear range.
You must press the brake pedal to move the shift lever
out of PARK (refer to “Brake/Transmission Shift Inter-
lock System” in this section). To drive, move the shift
lever from PARK or NEUTRAL to the DRIVE position.
The electronically-controlled transmission provides a
precise shift schedule. The transmission electronics are
self-calibrating; therefore, the first few shifts on a new
vehicle may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within a few
hundred miles (kilometers).
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You should now be able to drive out following the trench
you just created at a 45-degree angle.
WARNING!
There is an increased risk of rollover when crossing
an obstacle, at any angle, with steep sides.
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake and
accelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.
CAUTION!
Do not attempt to cross a log with a greater diameter
than the running ground clearance or the vehicle will
become high-centered.
Getting High-Centered
If you get hung up or high-centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody and
what is the best direction to recover the vehicle. Depend-
ing on what you are in contact with, jack the vehicle up
and place a few rocks under the tires so the weight is off
of the high point when you let the vehicle down. You can
also try rocking the vehicle or winching the vehicle off
the object.
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and maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a fresh#bite#into the surface and will usually
provide enough traction to complete the climb. If you do
not make it to the top, place the vehicle in REVERSE and
back straight down the grade using engine resistance
along with the vehicle brakes.
WARNING!
Never attempt to climb a hill at an angle or turn
around on a steep grade. Driving across an incline
increases the risk of a rollover, which may result in
severe injury.
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.
WARNING!
Do not descend a steep grade in NEUTRAL. Use
vehicle brakes in conjunction with engine braking.
Descending a grade too fast could cause you to lose
control and be seriously injured or killed.
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Driving Across An Incline
If at all possible, avoid driving across an incline. If it is
necessary, know your vehicle’s abilities. Driving across
an incline places more weight on the downhill wheels,
which increases the possibilities of a downhill slide or
rollover. Make sure the surface has good traction with
firm and stable soils. If possible, transverse the incline at
an angle heading slightly up or down.
WARNING!
Driving across an incline increases the risk of a
rollover , which may result in severe injury.
If You Stall Or Begin To Lose Headway
If you stall or begin to lose headway while climbing a
steep hill, allow your vehicle to come to a stop and
immediately apply the brake. Restart the engine and shift
into REVERSE. Back slowly down the hill allowing
engine braking to control the descent and apply your
brakes, if necessary, but do not allow the tires to lock.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle, which may result in
severe injury. Always back carefully straight down a
hill in REVERSE. Never back down a hill in NEU-
TRAL using only the vehicle brakes. Never drive
diagonally across a hill, always drive straight up or
down.
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Driving Through Water
Extreme care should be taken crossing any type of water.
Water crossings should be avoided, if possible, and only
be attempted when necessary in a safe, responsible
manner. You should only drive through areas which are
designated and approved. You should tread lightly and
avoid damage to the environment. You should know
your vehicle’s abilities and be able to recover it if
something goes wrong. You should never stop or shut a
vehicle off when crossing deep water unless you ingested
water into the engine air intake. If the engine stalls, do
not attempt to restart it. Determine if it has ingested
water first. The key to any crossing is low and slow. Shift
into first gear (manual transmission), or DRIVE (auto-
matic transmission), with the transfer case in the 4L
(Low) position and proceed very slowly with a constant
slow speed {3 to 5 mph (5 to 8 km/h) maximum} and
light throttle. Keep the vehicle moving; do not try to
accelerate through the crossing. After crossing any water
higher than the bottom of the axle differentials, you
should inspect all of the vehicle fluids for signs of water
ingestion.
CAUTION!
•Water ingestion into the axles, transmission, trans-
fer case, engine or vehicle interior can occur if you
drive too fast or through too deep of water. Water
can cause permanent damage to engine, driveline
or other vehicle components, and your brakes will
be less effective once wet and/or muddy.
•This vehicle is capable of crossing through water at
a depth of 30 inches (76 cm) at speeds no greater
than 5 mph (8 km/h). Water ingestion can occur
causing damage to your vehicle.
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•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, fan, 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 a collision. 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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In the event power assist is lost for any reason (for
example, repeated brake applications with the engine
OFF) the brakes will still function. The effort required to
brake the vehicle will be much greater than that required
with the power system operating.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Hill Start Assist (HSA), Electronic Roll
Mitigation (ERM), Electronic Stability Control (ESC),
Trailer Sway Control (TSC), and Hill Descent Control
(HDC). All of these systems work together to enhance
vehicle stability and control in various driving condi-
tions, and are commonly referred to as ESC.
Anti-Lock Brake System (ABS)
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.
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The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
WARNING!
•Pumping of the Anti-Lock Brakes will diminish
their effectiveness and may lead to a collision.
Pumping makes the stopping distance longer. Just
press firmly on your brake pedal when you need to
slow down or stop.
(Continued)
WARNING!(Continued)
•The Anti-Lock Brake System (ABS) cannot prevent
the natural laws of physics from acting on the
vehicle, nor can they increase braking or steering
efficiency beyond that afforded by the condition of
the vehicle brakes and tires or the traction afforded.
•The ABS cannot prevent collisions, including those
resulting from excessive speed in turns, following
another vehicle too closely, or hydroplaning.
•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.
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