2021 JEEP WRANGLER Owner handbook (in English)

After Starting
The idle speed is controlled automatically,
and it will decrease as the engine warms up.
Normal Starting — Diesel Engine
1. The gear selector must be in the NEU-
TRAL or PARK position before you can
start the engine.
2. Turn the ignition key to 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. Tip Start Feature (Automatic Transmission
Only)
Do notpress the accelerator. Turn the
ignition key 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 willdisengage automatically in 25 seconds.
If this occurs, turn the ignition switch to
the LOCK position, wait 25 to 30 sec-
onds, then repeat the “Normal Starting”
procedure.
NOTE:
The starter motor may run up to 30 sec-
onds in very cold conditions until the
engine is started. The starter can be dis-
engaged by turning the ignition key to
the OFF position, if required.
5. Without Tip Start Feature (Manual Trans-
mission Only)
Turn the ignition switch to the START
position and release when the engine
starts. If the engine fails to start within
10 seconds, turn the ignition switch to
the LOCK position, wait 10 to 15 sec-
onds, then repeat the “Normal Starting”
procedure.
6. After the engine starts, allow it to idle for
approximately 30 seconds before driving.
This allows oil to circulate and lubricate
the turbocharger.
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), oper-
ate the engine at moderate speeds for five
minutes before full loads are applied.
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
119

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 assures
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 itdown. This idle period will allow the lubricat-
ing oil and coolant to carry excess heat away
from the combustion chamber, bearings, in-
ternal components, and turbocharger. This is
especially important for turbocharged,
charge air cooled engines.
TURBOCHARGER "COOL DOWN" CHART
Driving
ConditionsLoad Turbocharger
TemperatureIdle Time (In Minutes)
Before Shut Down
Stop & Go Empty Cool Less than 1
Stop & Go Medium Warm 1
Highway Speeds Medium Warm 2
City Traffic Max. GCWR Warm 3
Highway Speeds Max. GCWR Warm 4
Uphill Grade Max. GCWR Hot 5
STARTING AND OPERATING
120

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 acceleration
within the limits of local traffic laws contrib-
utes to a good break-in. Wide-open throttle
acceleration in low gear can be detrimental
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 un-
der which vehicle operations will occur. For
the recommended viscosity and quality
grades, refer to “Dealer Service” in “Servic-
ing And Maintenance”.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.
NOTE:
A new engine may consume some oil during
its first few thousand miles (kilometers) of
operation. This should be considered a nor-
mal part of the break-in and not interpreted
as a problem.
PARKING BRAKE
Before exiting the vehicle, make sure that the
parking brake is fully applied. Also, be cer-
tain to leave an automatic transmission in
PARK, or manual transmission in REVERSE
or FIRST gear.
The parking brake lever is located in the
center console. To apply the parking brake,
pull the lever up as firmly as possible. To
release the parking brake, pull the lever up
slightly, push the center button, then lower
the lever completely.When the parking brake is applied with the
ignition switch ON, the “Brake Warning Light”
in the instrument cluster will illuminate.
NOTE:
• When the parking brake is applied and the
automatic transmission is placed in gear,
the “Brake Warning Light” will flash. If
vehicle speed is detected, a chime will
sound to alert the driver. Fully release the
parking brake before attempting to move
the vehicle.
Parking Brake Lever
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• This light only shows that the parking brake
is applied. It does not show the degree of
brake application.
When parking on a hill, it is important to turn
the front wheels toward the curb on a down-
hill grade and away from the curb on an uphill
grade. For vehicles equipped with an auto-
matic transmission, apply the parking brake
before placing the gear selector in PARK,
otherwise the load on the transmission lock-
ing mechanism may make it difficult to move
the gear selector out of PARK. The parking
brake should always be applied whenever the
driver is not in the vehicle.
WARNING!
• Never use the PARK position on an au-
tomatic transmission as a substitute for
the parking brake. Always apply the
parking brake fully when parked to guard
WARNING!
against vehicle movement and possible
injury or damage.
• 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 un-
attended 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.
• Be sure the parking brake is fully disen-
gaged before driving; failure to do so can
lead to brake failure and a collision.
WARNING!
• Always fully apply the parking brake
when leaving your vehicle or it may roll
and cause damage or injury. Also, be
certain to leave an automatic transmis-
sion in PARK, a manual transmission in
REVERSE or first gear. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the “Brake Warning Light” remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.
STARTING AND OPERATING
122

MANUAL TRANSMISSION —
IF EQUIPPED
WARNING!
You or others could be injured if you leave
the vehicle unattended without having the
parking brake fully applied. The parking
brake should always be applied when the
driver is not in the vehicle, especially on an
incline.
CAUTION!
Never drive with your foot resting on the
clutch pedal, or attempt to hold the ve-
hicle on a hill with the clutch pedal par-
CAUTION!
tially engaged, as this will cause abnormal
wear on the clutch.
NOTE:
During cold weather, you may experience
increased effort in shifting until the transmis-
sion fluid warms up. This is normal.
Shifting
Fully press the clutch pedal before shifting
gears. As you release the clutch pedal, lightly
press the accelerator pedal.
You should always use first gear when starting
from a standing position.
NOTE:
A certain amount of noise from the transmis-
sion is normal. This noise can be most notice-
able when the vehicle is idling in NEUTRAL
with the clutch engaged (clutch pedal re-
leased), but it may also be heard when driv-
ing. The noise may also be more noticeable
when the transmission is warm. This noise is
normal and is not an indication of a problem
with your clutch or transmission.
Shift Pattern
123

Recommended Vehicle Shift Speeds
To utilize your manual transmission effi-
ciently for both fuel economy and perfor-
mance, it should be upshifted as listed inrecommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When
heavily loaded or pulling a trailer these rec-
ommended 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 significantly less.
Downshifting
Moving from a high gear down to a lower gear
is recommended to preserve brakes when
driving down steep hills. In addition, down-
shifting at the right time provides better ac-
celeration 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 ve-
hicle could skid.
CAUTION!
• Skipping gears and downshifting into
lower gears at higher vehicle speeds can
damage the engine and clutch systems,
Any attempt to shift into lower gear with
clutch pedal depressed may result dam-
age to the clutch system. Shifting into
CAUTION!
lower gear and releasing the clutch may
result in engine damage.
• When descending a hill, be very careful
to downshift one gear at a time to pre-
vent overspeeding the engine which can
cause engine damage, and/or clutch
damage, even if the clutch pedal is
pressed. If transfer case is in low range
the vehicle speeds to cause engine and
clutch damage are significantly lower.
• Failure to follow the maximum recom-
mended downshifting speeds may cause
the engine damage and/or damage the
STARTING AND OPERATING
124

CAUTION!
clutch, even if the clutch pedal is
pressed.
• Descending a hill in low range with
clutch pedal depressed could result in
clutch damage.
Maximum Recommended Downshift Speeds
CAUTION!
Failure to follow the maximum recom-
mended downshifting speeds may cause
the engine to overspeed and/or damage the
clutch disc, even if the clutch pedal is
pressed.
Manual Transmission Downshift Speeds in MPH (KM/H)
Gear Selection 6 to 5 5 to 4 4 to 3 3 to 2 2 to 1
Maximum Speed 80 (129) 70 (113) 50 (81) 30 (48) 15 (24)
NOTE:
Vehicle speeds shown in the chart above are
for 2H and 4H only, vehicle speeds in 4L
would be significantly less.Reverse Shifting
To shift into REVERSE, bring the vehicle to a
complete stop. Press the clutch and pause
briefly to allow the gear train to stop rotating.
Beginning from the NEUTRAL position, move
the gear selector in one quick, smooth motion
straight across and into the REVERSE area
(the driver will feel a firm “click” as the
shifter passes the “knock-over”). Complete
the shift by pulling the gear selector into
REVERSE.The “knock-over” provides a resistance to the
driver from accidentally entering the RE-
VERSE shift area and warns the driver that
they are about to shift the transmission into
REVERSE. Due to this feature, a slow shift to
REVERSE can be perceived as a high shift
effort.
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AUTOMATIC
TRANSMISSION — IF
EQUIPPED
CAUTION!
Damage to the transmission may occur if
the following precautions are not ob-
served:
• 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.
NOTE:
You must press and hold the brake pedal
while shifting out of PARK.
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 gear selector out of
PARK with the brake pedal released.
Make sure the transmission is in PARK
before exiting 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
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
WARNING!
exit a vehicle while the engine is run-
ning. Before exiting a vehicle always
come to a complete stop, then apply the
parking brake, shift the transmission
into PARK, turn the engine OFF, and
remove the ignition key. Once the key is
removed, the transmission is locked in
PARK, securing the vehicle against un-
wanted movement.
• When exiting the vehicle, always remove
the ignition key from the vehicle and
lock the vehicle.
• Never leave children alone in a vehicle,
or with access to an unlocked vehicle.
Allowing children to be in a vehicle un-
attended 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 ignition key in or near
the vehicle (or in a location accessible to
children). A child could operate power
STARTING AND OPERATING
126