2021 JEEP WRANGLER UNLIMITED brake

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
140
If the vehicle is not in PARK and the driver exits
the vehicle with the engine running, 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
Driver’s door is removed
Vehicle speed is 1.2 mph (2.0 km/h) orless
Driver’s seat belt is unbuckled
Driver’s door is ajar
Brake pedal is not depressed
The MESSAGE “AutoPark Engaged Shift to P
then Shift to Gear ” will display in the instru -
ment cluster. NOTE:
In some cases the ParkSense graphic will be
displayed in the instrument cluster. In these
cases, the shifter must be returned to “P” to
select desired gear.
If the driver shifts into PARK while moving, the
vehicle may AutoPark.
AutoPark will engage
ONLY when vehicle
speed is 1.2 mph (2.0 km/h) or less.
The MESSAGE “Vehicle Speed is Too High to
Shift to P ” will be displayed in the instrument
cluster if vehicle speed is above 1.2 mph
(2.0 km/h). 4WD LOW
AutoPark will be disabled when operating the
vehicle in 4WD LOW.
The MESSAGE “
AutoPark Disabled ” will be
displayed in the instrument cluster.
Additional customer warnings will be given
when both of these conditions are met:
Vehicle is not in PARK
Driver’s door is ajar
The MESSAGE “ AutoPark Not Engaged ” will
be displayed in the instrument cluster. A
warning chime will continue until you shift
the vehicle into PARK or the driver’s door is
closed.
ALWAYS DO A VISUAL CHECK
that your vehicle
is in PARK by looking for the "P" in the
instrument cluster display and on the shifter.
As an added precaution, always apply the
parking brake when exiting the vehicle.
WARNING!
If vehicle speed is above 1.2 mph
(2.0 km/h), the transmission will default
to NEUTRAL until the vehicle speed drops
below 1.2 mph (1.9 km/h). A vehicle left
in the NEUTRAL position can roll. As an
added precaution, always apply the
parking brake when exiting the vehicle.
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143
(Continued)
ENGINE BREAK-IN
RECOMMENDATIONS
A long break-in period is not required for the
engine and drivetrain (transmission and axle)
in your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles
(100 km), speeds up to 50 or 55 mph (80 or
90 km/h) are desirable.
While cruising, brief full-throttle accelera-
tion within the limits of local traffic laws
contributes to a good break-in. Wide-open
throttle acceleration in low gear can be detri -
mental and should be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving
type lubricant. Oil changes should be consis -
tent with anticipated climate conditions
under which vehicle operations will occur.
For the recommended viscosity and quality
grades, refer to “Fluids And Lubricants” in
“Technical Specifications”. NOTE:
A new engine may consume some oil during
its first few thousand miles (kilometers) of
operation. This should be considered a
normal part of the break-in and not inter
-
preted as a problem.
AUTOMATIC
TRANSMISSION
NOTE:
You must press and hold the brake pedal
while shifting out of PARK. CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
CAUTION!
Shift into or out of PARK or REVERSE
only after the vehicle has come to a
complete stop.
Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
Before shifting into any gear, make sure
your foot is firmly pressing the brake
pedal.
WARNING!
Never use the PARK position as a substi -
tute for the parking brake. Always apply
the parking brake fully when exiting the
vehicle to guard against vehicle move-
ment and possible injury or damage.
Your vehicle could move and injure you
and others if it is not in PARK. Check by
trying to move the transmission gear
selector out of PARK with the brake
pedal released. Make sure the transmis-
sion is in PARK before exiting the
vehicle.
The transmission may not engage PARK
if the vehicle is moving. Always bring the
vehicle to a complete stop before
shifting to PARK, and verify that the
transmission gear position indicator
solidly indicates PARK (P) without
blinking. Ensure that the vehicle is
completely stopped, and the PARK posi -
tion is properly indicated, before exiting
the vehicle.
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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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147
4H
Four-Wheel Drive High Range — This range
maximizes torque to the front driveshaft,
forcing the front and rear wheels to rotate at
the same speed. This range provides addi-
tional traction for loose, slippery road
surfaces only.
NEUTRAL (N)
Neutral — This range disengages both the
front and rear driveshafts from the power -
train. To be used for flat towing behind
another vehicle.
Refer to “Recreational Towing” in this
chapter for further information. 4L
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maxi
-
mizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for
loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h).
The transfer case is intended to be driven in
the 2H position for normal street and
highway conditions, such as hard-surfaced
roads.
In the event that additional traction is
required, the transfer case 4H and 4L posi -
tions can be used to lock the front and rear
driveshafts together, forcing the front and
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 drive -
line components. Refer to “Shifting Proce -
dures” in this section for further information
on shifting into 4H or 4L. 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.
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.
Shifting Procedures
2H To 4H Or 4H To 2H
Shifting between 2H and 4H can be made
with the vehicle stopped or in motion. The
preferred shifting speed would be 0 to
45 mph (72 km/h). With the vehicle in
motion, the transfer case will engage/disen
-
WARNING!
You or others could be injured or killed if
you leave the vehicle unattended with the
transfer case in the NEUTRAL (N) position
without first fully engaging the parking
brake. The transfer case NEUTRAL (N)
position disengages both the front and rear
driveshafts from the powertrain, and will
allow the vehicle to roll, even if the
automatic transmission is in PARK. The
parking brake should always be applied
when the driver is not in the vehicle.
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149
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.
4H AUTO
Four-Wheel Drive Auto High Range — This
range sends power to the front wheels. The
four-wheel drive system will be automatically
engaged when the vehicle senses a loss of
traction. Additional traction for varying road
conditions.
4H PT
Four-Wheel Drive Part Time High Range —
This range maximizes torque to the front
driveshaft, forcing the front and rear wheels
to rotate at the same speed. This range
provides additional traction for loose, slip-
pery road surfaces only. NEUTRAL (N)
Neutral — This range disengages both the
front and rear driveshafts from the power
-
train. To be used for flat towing behind
another vehicle.
Refer to “Recreational Towing” in this
chapter for further information. 4L
Four-Wheel Drive Low Range — This range
provides low speed four-wheel drive. It maxi
-
mizes torque to the front driveshaft, forcing
the front and rear wheels to rotate at the
same speed. This range provides additional
traction and maximum pulling power for
loose, slippery road surfaces only. Do not
exceed 25 mph (40 km/h).
This transfer case is designed to be driven in
the 2H mode or 4H AUTO mode for normal
street and highway conditions on dry hard
surfaced roads. Driving the vehicle in 2H will
have greater fuel economy benefits as the
front axle is not engaged in 2H.
For variable driving conditions, the 4H AUTO
mode can be used. In this mode, the front
axle is engaged, but the vehicle's power is
sent to the rear wheels. Four-wheel drive will
be automatically engaged when the vehicle
senses a loss of traction. Because the front
axle is engaged, this mode will result in lower
fuel economy than the 2H mode.
WARNING!
You or others could be injured or killed if
you leave the vehicle unattended with the
transfer case in the NEUTRAL (N) position
without first fully engaging the parking
brake. The transfer case NEUTRAL (N)
position disengages both the front and rear
driveshafts from the powertrain, and will
allow the vehicle to roll, even if the
automatic transmission is in PARK. The
parking brake should always be applied
when the driver is not in the vehicle.
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153
NOTE:
The stabilizer/sway bar may be torque locked
due to left and right suspension height
differences. This condition is due to driving
surface differences or vehicle loading. In
order for the stabilizer/sway bar to discon-
nect/reconnect, the right and left halves of
the bar must be aligned. This alignment may
require that the vehicle be driven onto level
ground or rocked from side to side.
To return to on-road mode, push the SWAY
BAR switch again.
STOP/START SYSTEM —
AUTOMATIC TRANSMISSION
(IF EQUIPPED)

The Stop/Start function is developed to
reduce fuel consumption. The system will
stop the engine automatically during a
vehicle stop if the required conditions are
met. Releasing the brake pedal or pressing
the accelerator pedal will automatically
re-start the engine.
Engine Stop/Start (ESS) vehicles have been
upgraded with a heavy duty starter,
enhanced battery, and other upgraded
engine parts, to handle the additional engine
starts.
NOTE:
It is recommended that the Stop/Start
System be disabled during off-road use. Secondary Battery
Your vehicle may be equipped with a
secondary battery used to power the Stop/
Start system and the 12 Volt vehicle elec
-
trical system. The secondary battery is
located behind the wheel well for the front
driver’s side wheel.
Battery Locations
WARNING!
If the stabilizer/sway bar will not return to
on-road mode, the “Sway Bar Indicator
Light” will flash in the instrument cluster
and vehicle stability may be reduced. Do
not attempt to drive the vehicle over
18 mph (29 km/h). Driving faster than
18 mph (29 km/h) with a disconnected
stabilizer/sway bar may contribute to the
loss of vehicle control, which could result
in serious injury.
1 — Primary Battery
2 — Secondary Battery
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154
Automatic Mode
The Stop/Start feature is enabled
after every normal customer engine
start. At that time, the system will
go into STOP/START READY and if
all other conditions are met, can go into a
STOP/START AUTOSTOP ACTIVE
“Autostop” mode.
To Activate The Autostop Mode, The Following
Must Occur:
The system must be in STOP/START
READY state. A STOP/START READY
message will be displayed in the instru -
ment cluster display within the Stop/Start
section. Refer to “Instrument Cluster” in
“Getting To Know Your Instrument Panel”
in your Owner’s Manual for further infor -
mation.
The vehicle must be completely stopped.
The shifter must be in a forward gear and
the brake pedal depressed.
The engine will shut down, the tachometer
will move to the zero position and the Stop/
Start telltale will illuminate indicating you
are in Autostop. Customer settings will be
maintained upon return to an engine running
condition. Refer to the “Stop/Start System” in the
“Starting And Operating” section located in
your Owner’s Manual for further information.
Possible Reasons The Engine Does Not
Autostop
Prior to engine shut down, the system will
check many safety and comfort conditions to
see if they are fulfilled. Detailed information
about the operation of the Stop/Start system
may be viewed in the instrument cluster
display Stop/Start Screen. In the following
situations, the engine will not stop:
Driver’s seat belt is not buckled.
Driver’s door is not closed.
Battery temperature is too warm or cold.
Battery charge is low.
The vehicle is on a steep grade.
Cabin heating or cooling is in process and
an acceptable cabin temperature has not
been achieved.
HVAC is set to full defrost mode at a high
blower speed.
HVAC set to MAX A/C.
Engine has not reached normal operating
temperature.
Engine temperature too high.
The transmission is not in a forward gear.
Hood is open.
Transfer case is in 4L or Neutral.
Brake pedal is not pressed with sufficient
pressure.
Other Factors Which Can Inhibit Autostop
Include:
Accelerator pedal input.
Vehicle speed threshold not achieved from
previous auto-stop.
Steering angle beyond threshold. (ESS
Models Only)
ACC is on and speed is set.
Vehicle is at high altitude.
System fault present.
It may be possible for the vehicle to be driven
several times without the Stop/Start system
going into a STOP/START READY state
under more extreme conditions of the items
listed above.
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