stop start JEEP WRANGLER UNLIMITED 2021 Owner handbook (in English)

85
The cluster icon and switch indicator light
will flash when HDC deactivates due to
overheated brakes. The flashing will stop
and HDC will activate again once the
brakes have cooled sufficiently.
Hill Start Assist (HSA)

The Hill Start Assist (HSA) system is designed to
mitigate roll back from a complete stop while on
an incline. If the driver releases the brake while
stopped on an incline, HSA will continue to hold
the brake pressure for a short period. If the driver
does not apply the throttle before this time
expires, the system will release brake pressure
and the vehicle will roll down the hill as normal.
The following conditions must be met in
order for HSA to activate:
The feature must be enabled
The vehicle must be stopped
Park brake must be off
Driver door must be closed. (If the doors
are attached, then the door must be
closed. If the doors are detached then the
driver's seatbelt must be buckled)
The vehicle must be on a sufficient grade
The gear selection must match vehicle
uphill direction (i.e., vehicle facing uphill
is in forward gear; vehicle backing uphill is
in REVERSE (R) gear)
HSA will work in REVERSE gear and all
forward gears. The system will not activate
if the transmission is in PARK (P) or
NEUTRAL (N). For vehicles equipped with
a manual transmission, if the clutch is
pressed, HSA will remain active.
Disabling And Enabling HSA
This feature can be turned on or turned off.
To change the current setting, refer to
“Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” for further
information.
WARNING!
HDC is only intended to assist the driver in
controlling vehicle speed when descending
hills. The driver must remain attentive to
the driving conditions and is responsible
for maintaining a safe vehicle speed.
WARNING!
There may be situations where the Hill
Start Assist (HSA) will not activate and
slight rolling may occur, such as on minor
hills or with a loaded vehicle, or while
pulling a trailer. HSA is not a substitute for
active driving involvement. It is always the
driver’s responsibility to be attentive to
distance to other vehicles, people, and
objects, and most importantly brake
operation to ensure safe operation of the
vehicle under all road conditions. Your
complete attention is always required
while driving to maintain safe control of
your vehicle. Failure to follow these
warnings can result in a collision or serious
personal injury.
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SAFETY
86
Towing With HSA
HSA will also provide assistance to mitigate
roll back while towing a trailer.
Ready Alert Braking (RAB)
Ready Alert Braking (RAB) may reduce the
time required to reach full braking during
emergency braking situations. It anticipates
when an emergency braking situation may
occur by monitoring how fast the throttle is
released by the driver. The Electronic Brake
Control (EBC) system will prepare the brake
system for a panic stop.
Rain Brake Support (RBS)
Rain Brake Support (RBS) may improve
braking performance in wet conditions. It
will periodically apply a small amount of
brake pressure to remove any water buildup
on the front brake rotors. It functions when
the windshield wipers are in LO or HI speed.
When RBS is active, there is no notification
to the driver and no driver interaction is
required.
Trailer Sway Control (TSC)
Trailer Sway Control (TSC) uses sensors in
the vehicle to recognize an excessively
swaying trailer and will take the appropriate
actions to attempt to stop the sway. TSC will
become active automatically once an exces-
sively swaying trailer is recognized.

NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda-
tions. Refer to “Trailer Towing” in “Starting
And Operating” for further information.

When TSC is functioning, the “ESC Activa -
tion/Malfunction Indicator Light” will flash,
the engine power may be reduced and you
may feel the brakes being applied to indi -
vidual wheels to attempt to stop the trailer
from swaying. TSC is disabled when the ESC
system is in the “Partial Off” or “Full Off”
modes.
WARNING!
If you use a trailer brake controller with
your trailer, the trailer brakes may be
activated and deactivated with the brake
switch. If so, there may not be enough
brake pressure to hold both the vehicle
and the trailer on a hill when the brake
pedal is released. In order to avoid
rolling down an incline while resuming
acceleration, manually activate the
trailer brake or apply more vehicle brake
pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the
transmission in PARK (P).
Failure to follow these warnings can
result in a collision or serious personal
injury. WARNING!
If TSC activates while driving, slow the
vehicle down, stop at the nearest safe
location, and adjust the trailer load to
eliminate trailer sway.
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SAFETY
100
(Continued)
(Continued)
equipped with Rear Seat BeltAlert). The
respective Seat Belt Reminder light will illu -
minate solid red. If the seat belt is not
buckled when the vehicle exceeds a speci -
fied speed, the Rear Seat Belt Reminder
light will flash red and a continuous chime
will sound for approximately 30 seconds if
there is no change of status of the rear seat
belt buckles. If a rear seat passenger
unbuckles a seat belt while the vehicle is
travelling, the warning sequence will start
again and the Rear Seat Belt Reminder Light
for that position will change from green to
red. This will alert the driver to stop the
vehicle until the rear seat passenger buckles
the seat belt again. All rear seat BeltAlert
lights will remain illuminated for approxi -
mately 60 seconds (if equipped with Rear
Seat BeltAlert).

The Belt Reminder light will indicate if a rear
seat is not occupied and the seat belt is
unbuckled . If the rear seat is removed (for
vehicles with a removable rear seat) the Belt
Reminder light will illuminate two dashes .

Driver and Front Passenger BeltAlert can be
activated or deactivated by an authorized
dealer. Rear Seat BeltAlert cannot be deacti -
vated. FCA does not recommend deacti -
vating BeltAlert. NOTE:
If Front BeltAlert has been deactivated, the
Front Seat Belt Reminder Light will turn on
and remain on until the driver and outboard
front seat passenger seat belts are buckled.
Lap/Shoulder Belts
All seating positions in your vehicle are
equipped with lap/shoulder belts.
The seat belt webbing retractor will lock only
during very sudden stops or collisions. This
feature allows the shoulder part of the seat
belt to move freely with you under normal
conditions. However, in a collision the seat
belt will lock and reduce your risk of striking
the inside of the vehicle or being thrown out
of the vehicle.
WARNING!
Relying on the air bags alone could lead
to more severe injuries in a collision. The
air bags work with your seat belt to
restrain you properly. In some collisions,
the air bags won’t deploy at all. Always
wear your seat belt even though you have
air bags.
In a collision, you and your passengers
can suffer much greater injuries if you
are not properly buckled up. You can
strike the interior of your vehicle or other
passengers, or you can be thrown out of
the vehicle. Always be sure you and
others in your vehicle are buckled up
properly.

It is dangerous to ride in a cargo area,
inside or outside of a vehicle. In a collision,
people riding in these areas are more likely
to be seriously injured or killed.

Do not allow people to ride in any area of
your vehicle that is not equipped with
seats and seat belts.

Be sure everyone in your vehicle is in a seat
and using a seat belt properly. Occupants,
including the driver, should always wear
their seat belts whether or not an air bag is
also provided at their seating position to
minimize the risk of severe injury or death
in the event of a crash.

WARNING! (Continued)
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SAFETY
116
(Continued)
NOTE:
After an accident, remember to cycle the
ignition to the STOP (OFF/LOCK) position
and remove the key from the ignition switch
to avoid draining the battery. Carefully check
the vehicle for fuel leaks in the engine
compartment and on the ground near the
engine compartment and fuel tank before
resetting the system and starting the engine.
If there are no fuel leaks or damage to the
vehicle electrical devices (e.g. headlights)
after an accident, reset the system by
following the procedure described below. If
you have any doubt, contact an authorized
dealer.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident
Response System functions after an event,
the ignition switch must be changed from
ignition START or ON/RUN to ignition OFF.
Carefully check the vehicle for fuel leaks in
the engine compartment and on the ground
near the engine compartment and fuel tank
before resetting the system and starting the
engine.
Maintaining Your Air Bag System
WARNING!

Modifications to any part of the air bag
system could cause it to fail when you need
it. You could be injured if the air bag
system is not there to protect you. Do not
modify the components or wiring,
including adding any kind of badges or
stickers to the steering wheel hub trim
cover or the upper passenger side of the
instrument panel. Do not modify the front
bumper, vehicle body structure, or add
aftermarket side steps or running boards.

It is dangerous to try to repair any part of
the air bag system yourself. Be sure to
tell anyone who works on your vehicle
that it has an air bag system.
Do not attempt to modify any part of your
air bag system. The air bag may inflate
accidentally or may not function properly
if modifications are made. Take your
vehicle to an authorized dealer for any air
bag system service. If your seat,
including your trim cover and cushion,
needs to be serviced in any way
(including removal or loosening/
tightening of seat attachment bolts),
take the vehicle to an authorized dealer.
Only manufacturer approved seat
accessories may be used. If it is
necessary to modify the air bag system
for persons with disabilities, contact an
authorized dealer.
WARNING! (Continued)
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138
STARTING AND OPERATING
STARTING THE ENGINE
Before starting your vehicle, adjust your seat,
adjust both inside and outside mirrors, and
fasten your seat belts.
Normal Starting — Gasoline Engine
To Turn On The Engine Using The ENGINE
START/STOP Button
1. The transmission must be in PARK (P) orNEUTRAL (N).
2. Press and hold the brake pedal while pushing the ENGINE START/STOP
button once.
3. The system takes over and attempts to start the vehicle. If the vehicle fails to
start, the starter will disengage automat -
ically after 10 seconds.
4. If you wish to stop the cranking of the engine prior to the engine starting, push
the ENGINE START/STOP button again.
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or
pressing the accelerator pedal.
To Turn Off The Engine Using ENGINE START/
STOP Button
1. Place the gear selector in PARK, then push and release the ENGINE START/
STOP button. 2. The ignition will return to the OFF mode.
3. If the gear selector is not in PARK (with
vehicle stopped) and the ENGINE
START/STOP button is pushed once, the
transmission will automatically select
PARK and the engine will turn off,
however the ignition will remain in the
ACC mode (NOT the OFF mode). Never
leave a vehicle out of the PARK position,
or it could roll.

4. If the gear selector is in NEUTRAL, and the vehicle speed is below 5 mph (8 km/h),
pushing the ENGINE START/STOP button
once will turn the engine off. The ignition
will remain in the ACC mode.

5. If the vehicle speed is above 5 mph (8 km/h), the ENGINE START/STOP
button must be held for two seconds (or
three short pushes in a row) to turn the
engine off. The ignition will remain in the
ACC mode (NOT the OFF mode) if the
engine is turned off when the transmis -
sion is not in PARK.
WARNING!
When exiting the vehicle, always remove
the key fob from the ignition and lock
your vehicle.
Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Allowing children to be in a vehicle unat -
tended is dangerous for a number of
reasons. A child or others could be seri -
ously or fatally injured. Children should
be warned not to touch the parking
brake, brake pedal or the gear selector.
Do not leave the key fob in or near the
vehicle, or in a location accessible to
children. A child could operate power
windows, other controls, or move the
vehicle.
Do not leave children or animals inside
parked vehicles in hot weather. Interior
heat build-up may cause serious injury or
death.
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139
NOTE:
The system will automatically time out and
the ignition will cycle to the OFF mode after
30 minutes of inactivity if the ignition is left
in the ACC or RUN (engine not running)
mode and the transmission is in PARK.
ENGINE START/STOP Button Functions — With
Driver’s Foot OFF The Brake Pedal (In PARK Or
NEUTRAL Position)
The ENGINE START/STOP button operates
similar to an ignition switch. It has three
modes: OFF, ACC, and RUN. To change the
ignition modes without starting the vehicle
and use the accessories, follow these steps:

1. Starting with the ignition in the OFF mode,

2. Push the ENGINE START/STOP button onceto place the ignition to the ACC mode (instru -
ment cluster will display “ACC”),

3. Push the ENGINE START/STOP button a second time to place the ignition to the
RUN mode (instrument cluster will
display “ON/RUN”),
4. Push the ENGINE START/STOP button a third time to return the ignition to the
OFF mode (instrument cluster will
display “OFF”).AutoPark
AutoPark is a supplemental feature to assist
in placing the vehicle in PARK should the
situations on the following pages occur. It is
a back up system and should not be relied
upon as the primary method by which the
driver shifts the vehicle into PARK.
The conditions under which AutoPark will
engage are outlined on the following pages. If the vehicle is not in PARK and the driver turns
off the engine, the vehicle may AutoPark.
AutoPark will engage when all of these
conditions are met:
Vehicle is equipped with an 8-speed trans-
mission
Driver’s door is ajar or in conditions where
driver door is removed an additional
trigger would be if the driver is off the seat
(seat pad sensor detects driver missing).
Vehicle is not in PARK
Vehicle speed is 0 mph (0 km/h)
Ignition switched from RUN to OFF
NOTE:
For Keyless Enter-N-Go equipped vehicles,
The engine will turn off and the ignition
switch will change to ACC mode. After
30 minutes the ignition switches to OFF
automatically, unless the driver turns the
ignition switch OFF.
WARNING!
Driver inattention could lead to failure to
place the vehicle in PARK. ALWAYS DO
A VISUAL CHECK that your vehicle is in
PARK by verifying that a solid (not
blinking) “P” is indicated in the instru -
ment cluster display and on the gear
selector. If the "P" indicator is blinking,
your vehicle is not in PARK. As an added
precaution, always apply the parking
brake when exiting the vehicle.
AutoPark is a supplemental feature. It is
not designed to replace the need to shift
your vehicle into PARK. It is a back up
system and should not be relied upon as
the primary method by which the driver
shifts the vehicle into PARK.
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STARTING AND OPERATING
142
Diesel Engine Idling — In Cold Weather
Avoid prolonged idling in ambient tempera-
tures below 0°F (-18°C). Long periods of
idling may be harmful to your engine
because combustion chamber temperatures
can drop so low that the fuel may not burn
completely. Incomplete combustion allows
carbon and varnish to form on piston rings
and injector nozzles. Also, the unburned fuel
can enter the crankcase, diluting the oil and
causing rapid wear to the engine.
Stopping the Engine
The following chart should be used as a
guide in determining the amount of engine
idle time required to sufficiently cool down
the turbocharger before shut down,
depending upon the type of driving and the
amount of cargo.
Before turning off your turbo diesel engine,
always allow the engine to return to normal idle
speed and run for several seconds. This
ensures proper lubrication of the turbocharger. This is particularly necessary after any period
of hard driving.
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five minutes before shutting
it down. This idle period will allow the lubri
-
cating oil and coolant to carry excess heat
away from the combustion chamber, bear -
ings, internal components, and turbo -
charger. This is especially important for
turbocharged, charge air cooled engines.
Turbocharger "Cool Down" Chart
Driving
Conditions Load
Turbocharger
Temperature Idle Time (In Minutes)
Before Shut Down
Stop & Go EmptyCoolLess than 1
Stop & Go Medium Warm1
Highway Speeds MediumWarm2
City Traffic Max. GCWR Warm3
Highway Speeds Max. GCWR Warm4
Uphill Grade Max. GCWR Hot5
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STARTING AND OPERATING
144
(Continued)
Ignition Park Interlock
This vehicle is equipped with an Ignition
Park Interlock which requires the transmis-
sion to be in PARK before the ignition can be
turned to the OFF mode. This helps the
driver avoid inadvertently leaving the vehicle
without placing the transmission in PARK.
This system also locks the transmission in
PARK whenever the ignition is in the OFF
mode. NOTE:
The transmission is NOT locked in PARK
when the ignition is in the ACC mode (even
though the engine will be off). Ensure that
the transmission is in PARK, and the ignition
is
OFF (not in ACC mode) before exiting the
vehicle.
Brake/Transmission Shift Interlock
System
This vehicle is equipped with a Brake Trans -
mission Shift Interlock system (BTSI) that
holds the transmission gear selector in PARK
unless the brakes are applied. To shift the
transmission out of PARK, the engine must
be running and the brake pedal must be
pressed. The brake pedal must also be
pressed to shift from NEUTRAL into DRIVE
or REVERSE when the vehicle is stopped or
moving at low speeds.
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
reverse. 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.
Unintended movement of a vehicle could
injure those in or near the vehicle. As
with all vehicles, you should never exit a
vehicle while the engine is running.
Before exiting a vehicle, always come to
a complete stop, then apply the parking
brake, shift the transmission into PARK,
and turn the ignition OFF. When the igni -
tion is in the OFF mode, the transmis-
sion is locked in PARK, securing the
vehicle against unwanted movement.
When exiting the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
WARNING! (Continued)
Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Allowing children to be in a vehicle unat -
tended is dangerous for a number of
reasons. A child or others could be seri -
ously or fatally injured. Children should
be warned not to touch the parking
brake, brake pedal or the transmission
gear selector.
Do not leave the key fob in or near the
vehicle (or in a location accessible to
children), and do not leave the ignition
in the ACC or ON/RUN mode. A child
could operate power windows, other
controls, or move the vehicle.
WARNING! (Continued)
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STARTING AND OPERATING
146
The transmission will automatically down-
shift to FIRST gear when coming to a stop.
After a stop, the driver should manually
upshift (+) the transmission as the vehicle
is accelerated.
You can start out, from a stop, in FIRST or
SECOND gear (or THIRD gear, in 4L
range). Tapping (+) (at a stop) will allow
starting in SECOND gear. Starting out in
SECOND or THIRD gear can be helpful in
snowy or icy conditions.
If a requested downshift would cause the
engine to over-speed, that shift will not
occur.
The system will ignore attempts to upshift
at too low of a vehicle speed.
Holding the gear selector in the (-) posi -
tion will downshift the transmission to the
lowest gear possible at the current speed.
Transmission shifting will be more notice-
able when AutoStick is enabled.
The system may revert to automatic shift
mode if a fault or overheat condition is
detected. NOTE:
When Hill Descent Control is enabled, Auto
-
Stick is not active.
To disengage AutoStick mode, return the
gear selector to the DRIVE position. You can
shift in or out of the AutoStick position at any
time without taking your foot off the acceler -
ator pedal.
FOUR–WHEEL DRIVE
OPERATION
Four-Position Transfer Case
Four-Wheel Drive Gear Selector
The transfer case provides four mode posi -
tions:
2H (Two-Wheel Drive High Range)
4H (Four-Wheel Drive High Range)
N (Neutral)
4L (Four-Wheel Drive Low Range)
For additional information on the appropriate
use of each transfer case mode position, see
the information below:
2H
Two-Wheel Drive High Range — This range is
for normal street and highway driving on dry,
hard surfaced roads.
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip and the
vehicle could skid, causing a collision or
personal injury.
WARNING!
Failure to engage a transfer case position
completely can cause transfer case
damage or loss of power and vehicle
control. You could have a collision. Do not
drive the vehicle unless the transfer case
is fully engaged.
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STARTING AND OPERATING
148
gage faster if you momentarily release the
accelerator pedal after completing the shift.
Do not accelerate while shifting the transfer
case. Apply a constant force when shifting
the transfer case lever.
NOTE:

Do not attempt to make a shift while only the
front or rear wheels are spinning. The front
and rear driveshaft speeds must be equal for
the shift to take place. Shifting while only
the front or rear wheels are spinning can
cause damage to the transfer case.

Delayed shifts out of four-wheel drive may
be experienced due to uneven tire wear,
low or uneven tire pressures, excessive
vehicle loading, or cold temperatures.
Shifting effort will increase with speed,
this is normal.
During cold weather, you may experience
increased effort in shifting until the transfer
case fluid warms up. This is normal.
4H To 4L Or 4L To 4H
With the vehicle rolling at 2 to 3 mph (3 to
5 km/h), shift the transmission into
NEUTRAL (N). While the vehicle is coasting
at 2 to 3 mph (3 to 5 km/h), shift the
transfer case lever firmly to the desired posi -
tion. Do not pause with the transfer case in
N (Neutral). Once the shift is completed,
place the transmission into DRIVE.
NOTE:
Shifting into or out of 4L is possible with the
vehicle completely stopped; however, diffi -
culty may occur due to the mating teeth not
being properly aligned. Several attempts may
be required for clutch teeth alignment and
shift completion to occur. The preferred
method is with the vehicle rolling at 2 to
3 mph (3 to 5 km/h). Avoid attempting to
engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
Five-Position Transfer Case
Four-Wheel Drive Gear Selector
The transfer case provides five mode posi -
tions:
2H (Two-Wheel Drive High Range)
4H AUTO (Four-Wheel Drive Auto High
Range)
4H PT (Four-Wheel Drive Part Time High
Range)
N (Neutral)
4L (Four-Wheel Drive Low Range)
WARNING!

Failure to engage a transfer case position
completely can cause transfer case damage or
loss of power and vehicle control. You could
have a collision. Do not drive the vehicle unless
the transfer case is fully engaged.

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