engine JEEP WRANGLER UNLIMITED 2015 User Guide

WARNING!
•It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal.
(Continued)

WARNING!(Continued)
•Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the transmission gear selector.
• Do not leave the ignition key in or near the vehicle
(or in a location accessible to children). A child
could operate power windows, other controls, or
move the vehicle.
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.
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STARTING AND OPERATING 431

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 move-
ment and possible injury or damage.
• Your vehicle could move and injure you and others
if it is not completely in PARK. Check by trying to
move the shift lever out of PARK with the brake
pedal released. Make sure the transmission is in
PARK before leaving the vehicle.
• It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal.
(Continued)

The following indicators should be used to ensure that
you have engaged the transmission into the PARK posi-
tion:
•When shifting into PARK, firmly move the shift lever
all the way forward and to the left until it stops and is
fully seated.
• Look at the transmission gear position display and
verify that it indicates the PARK position.
• With brake pedal released, verify that the shift lever
will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward. Shift into
REVERSE only after the vehicle has come to a complete
stop.
NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.

rear wheels to rotate at the same speed. The 4H and 4L
positions are intended for loose, slippery road surfaces
only and not intended for normal driving. Driving in the
4H and 4L positions on hard-surfaced roads will cause
increased tire wear and damage to the driveline compo-
nents. Refer to “Shifting Procedures” in this section for
further information on shifting into 4H or 4L.
The “4WD Indicator Light” (located in the instrument
cluster) alerts the driver that the vehicle is in four-wheel
drive, and the front and rear driveshafts are locked
together. The light will illuminate when the transfer case
is shifted into the 4H position.
NOTE:Do not attempt to shift when only the front or
rear wheels are spinning. The transfer case is not
equipped with a synchronizer, and the front and rear
driveshaft speeds must be equal for a shift to take place.
Shifting while the front or rear wheels are spinning at
different speeds can cause damage to the transfer case. When operating your vehicle in 4L, the engine speed will
be approximately three times (four times for Rubicon
models) that of the 2H or 4H positions at a given road
speed. Take care not to overspeed the engine.
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type, and circumference on each
wheel. Any difference will adversely affect shifting and
cause damage to the transfer case.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.

branches or other obstacles on the path? Can you safely
recover the vehicle if something goes wrong? If every-
thing looks good and you feel confident, shift the trans-
mission into a lower gear with 4L (Low) engaged, and
proceed with caution, maintaining your momentum as
you climb the hill.
Driving Up Hill
Once you have determined your ability to proceed and
have shifted into the appropriate gear, line your vehicle
up for the straightest possible run. Accelerate with an
easy constant throttle and apply more power as you start
up the hill. Do not race forward into a steep grade; the
abrupt change of grade could cause you to lose control. If
the front end begins to bounce, ease off the throttle
slightly to bring all four tires back on the ground. As you
approach the crest of the hill, ease off the throttle and
slowly proceed over the top. If the wheels start to slip as
you approach the crest of a hill, ease off the acceleratorand maintain headway by turning the steering wheel no
more than a 1/4 turn quickly back and forth. This will
provide a fresh
biteinto 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.

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!
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.
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 knowyour 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.
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A feature of the TCS system, Brake Limited Differential
(BLD), 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 ESC are in either the “Partial Off” or “Full Off”
modes. Refer to “Electronic Stability Control (ESC)” in
this section for further 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 veryquickly results in the best BAS assistance. To receive the
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.

WARNING!
•When in ESC Partial Off mode, the TCS function-
ality of ESC, (except for the limited slip feature
described in the TCS section), has been disabled
and the “ESC Off Indicator Light” will be illumi-
nated. When in ESC Partial Off mode, the engine
power reduction feature of TCS is disabled, and
the enhanced vehicle stability offered by the ESC
system is reduced.
• Trailer Sway control (TSC) is disabled when the
ESC system is in the ESC Partial Offmode.
ESC Full Off
This mode is entered by pressing and holding momen-
tarily pressing the ESC OFF switch for five seconds. In the
ESC Full Off mode, the engine torque reduction
and stability features are disabled. Therefore, the en-
hanced vehicle stability offered by ESC is unavailable. In
an emergency evasive maneuver, the ESC system will not
engage to assist in maintaining stability. “ESC Full Off”
mode is intended for off-highway or off-road use only.