2021 JEEP WRANGLER UNLIMITED engine

137
(Continued)
Periodic Safety Checks You Should Make
Outside The Vehicle
Tires

Examine tires for excessive tread wear and uneven
wear patterns. Check for stones, nails, glass, or
other objects lodged in the tread or sidewall.
Inspect the tread for cuts and cracks. Inspect side-
walls for cuts, cracks, and bulges. Check the wheel
nuts for tightness. Check the tires (including spare)
for proper cold inflation pressure.

Lights

Have someone observe the operation of brake
lights and exterior lights while you work the
controls. Check turn signal and high beam indi -
cator lights on the instrument panel.

Door Latches
Check for proper closing, latching, and
locking.
Fluid Leaks
Check area under vehicle after overnight
parking for fuel, coolant, oil, or other fluid
leaks. Also, if gasoline fumes are detected or
if fuel, or brake fluid leaks are suspected, the
cause should be located and corrected
immediately.
ALWAYS REMOVE THE EXISTING
FLOOR MAT FROM THE VEHICLE
before installing any other floor mat.
NEVER install or stack an additional
floor mat on top of an existing floor mat.
ONLY install floor mats designed to fit
your vehicle. NEVER install a floor mat
that cannot be properly attached and
secured to your vehicle. If a floor mat
needs to be replaced, only use a FCA
approved floor mat for the specific make,
model, and year of your vehicle.
ONLY use the driver’s side floor mat on
the driver’s side floor area. To check for
interference, with the vehicle properly
parked with the engine off, fully depress
the accelerator, the brake, and the
clutch pedal (if present) to check for
interference. If your floor mat interferes
with the operation of any pedal, or is not
secure to the floor, remove the floor mat
from the vehicle and place the floor mat
in your trunk.
ONLY use the passenger’s side floor mat
on the passenger’s side floor area.
WARNING! (Continued)
ALWAYS make sure objects cannot fall
or slide into the driver’s side floor area
when the vehicle is moving. Objects can
become trapped under accelerator,
brake, or clutch pedals and could cause
a loss of vehicle control.
NEVER place any objects under the floor
mat (e.g., towels, keys, etc.). These
objects could change the position of the
floor mat and may cause interference
with the accelerator, brake, or clutch
pedals.
If the vehicle carpet has been removed
and re-installed, always properly attach
carpet to the floor and check the floor
mat fasteners are secure to the vehicle
carpet. Fully depress each pedal to
check for interference with the acceler -
ator, brake, or clutch pedals then
re-install the floor mats.
It is recommended to only use mild soap
and water to clean your floor mats. After
cleaning, always check your floor mat
has been properly installed and is
secured to your vehicle using the floor
mat fasteners by lightly pulling mat.
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
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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141
NORMAL STARTING —
DIESEL ENGINE
1. The gear selector must be in theNEUTRAL or PARK position before you
can start the engine.
2. Place the ignition in the ON position.
3. Watch for the “Wait To Start Light” in the instrument cluster. Refer to “Instrument
Cluster” in “Getting To Know Your Instru -
ment Panel” for further review. It will
glow for two to ten seconds or more,
depending on engine temperature. When
the “Wait To Start Light” goes out, the
engine is ready to start.
4. After the engine starts, allow it to idle for approximately 30 seconds before driving.
This allows oil to circulate and lubricate
the turbocharger. Tip Start Feature:

5.
Do not press the accelerator. Cycle the igni -
tion to the START position and then release
it. The starter motor will continue to run,
and it will automatically disengage when
the engine is running. If the engine fails to
start, the starter will disengage automati -
cally in 25 seconds. If this occurs, cycle
the ignition to the LOCK position, wait 25
to 30 seconds, then repeat the “Normal
Starting” procedure.

NOTE:
The starter motor may run up to 30 seconds
in very cold conditions until the engine is
started. The starter can be disengaged by
cycling the ignition to the OFF position, if
required.
Diesel Engine Warm-Up
Avoid full throttle operation when the engine
is cold. When starting a cold engine, bring
the engine up to operating speed slowly to
allow the oil pressure to stabilize as the
engine warms up.
NOTE:
High-speed, no-load running of a cold engine
can result in excessive white smoke and poor
engine performance. No-load engine speeds
should be kept under 1,200 RPM during the
warm-up period, especially in cold, ambient
temperature conditions.
If temperatures are below 32°F (0°C),
operate the engine at moderate speeds for
5 minutes before full loads are applied.
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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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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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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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