2021 JEEP WRANGLER UNLIMITED oil

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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181
Bulb Replacement
NOTE:
Lens fogging can occur under certain atmo-
spheric conditions. This will usually clear as
atmospheric conditions change to allow the
condensation to change back into a vapor.
Turning the lamps on will usually accelerate
the clearing process.
Halogen Headlamps
NOTE:
We advise referring to an authorized dealer
for service.
1. Open hood and support using prop rod.
2. Remove the front grille. Turn the retainers along the top a quarter turn
counterclockwise and remove.
3. Pull the bottom of the grille away starting at one side and working toward the other.
4. Remove the three screws holding the headlamp to the vehicle.
5. Remove lamp from the vehicle.
6. Remove the lamp from the collar. 7. Grasp the bulb and turn a quarter turn
counterclockwise.
8. Pull the bulb from the housing.
9. Push connector locking tab to the unlock position.
10. Remove connector from bulb.
11. Push connector onto new bulb base, and push the connector locking tab to the
lock position.
12. Reinstall bulb housing. Rotate the bulb a quarter turn clockwise.
Front Park/Turn Signal
NOTE:
We advise referring to an authorized dealer
for service.
1. Remove the front wheel liner fasteners toaccess bulb sockets.
Wheel Liner
2. Turn the socket assembly a quarter turn counterclockwise and remove from
housing. Pull the bulb straight from the
socket to replace.
LED Front Side Marker
Please see an authorized dealer for service.
CAUTION!
Do not touch the new bulb with your
fingers. Oil contamination will severely
shorten bulb life. If the bulb comes in
contact with any oily surface, clean the
bulb with rubbing alcohol.
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IN CASE OF EMERGENCY
182
Halogen Front Fog Lamp
NOTE:
We advise referring to an authorized dealer
for service.
1. Reach under the vehicle to access theback of the front fog lamp.
2. Disconnect the wire harness connector from the front fog lamp connector recep -
tacle.
3. Firmly grasp the bulb by the two latch features and squeeze them together to
unlock the bulb from the back of the
front fog lamp housing.
4. Pull the bulb straight out from the keyed opening in the housing and then connect
the replacement bulb. LED Front Fog Lamp
Please see an authorized dealer for service.
Rear Tail, Stop, Turn Signal, And Backup
Lamp
1. Remove interior trim panel cap to access
single retaining screw for tail lamp
assembly.
Trim Cap
2. Remove retaining screw and disconnect electrical connector, then remove tail
lamp assembly from the vehicle.
NOTE:
If necessary, push in on the assembly tab
located inboard behind the lamp housing. Retaining Screw
3. Remove the three screws from assembly bracket to access bulb sockets.
Assembly Bracket
4. Rotate the appropriate socket a quarter turn counterclockwise, then remove it
from the housing.

5. Pull the bulb straight from the socket to replace.

CAUTION!
Do not touch the new bulb with your
fingers. Oil contamination will severely
shorten bulb life. If the bulb comes in
contact with any oily surface, clean the
bulb with rubbing alcohol.
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183
(Continued)
Center High Mounted Stop Lamp (CHMSL)
Please see an authorized dealer for service.
License Plate Lamps
1. Reach under the vehicle to access theback of the lamp.
2. Firmly grasp the bulb by the two latch features and squeeze them together to
unlock the bulb from the back of the
lamp housing.
Rear Fog Lamp
NOTE:
We advise referring to an authorized dealer
for service.
1. Reach under the vehicle to access theback of the fog lamp.
2. Disconnect the wire harness connector from the fog lamp connector receptacle.
3. Rotate the socket a quarter turn counter -
clockwise, then remove it from the
housing.
4. Pull the bulb straight out from the keyed opening in the housing and then connect
the replacement bulb and reassemble.
FUSES
General Information
The fuses protect electrical systems against
excessive current.
When a device does not work, you must
check the fuse element inside the blade fuse
for a break/melt.
Also, please be aware that when using power
outlets for extended periods of time with the
engine off may result in vehicle battery
discharge.
CAUTION!
Do not touch the new bulb with your
fingers. Oil contamination will severely
shorten bulb life. If the bulb comes in
contact with any oily surface, clean the
bulb with rubbing alcohol.
WARNING!
When replacing a blown fuse, always use
an appropriate replacement fuse with
the same amp rating as the original fuse.
Never replace a fuse with another fuse of
higher amp rating. Never replace a blown
fuse with metal wires or any other mate-
rial. Failure to use proper fuses may
result in serious personal injury, fire and/
or property damage.
Before replacing a fuse, make sure that
the ignition is off and that all the other
services are switched off and/or disen -
gaged.
If the replaced fuse blows again, contact
an authorized dealer.
If a general protection fuse for safety
systems (air bag system, braking
system), power unit systems (engine
system, gearbox system) or steering
system blows, contact an authorized
dealer.
CAUTION!
If it is necessary to wash the engine
compartment, take care not to directly hit
the fuse box, and the windshield wiper
motors with water.
WARNING! (Continued)
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189
F69–5 Amp Tan Motor Generator Unit MGU Belt Starter Generator (BSG) — If
Equipped
(*)
F70 –25 Amp Clear INJ/IGN COIL (GAS)/GLO PLUG MOD (DSL)
(*)
F71 – –Spare
F72 –10 Amp Red HD ELEC ACC PKG — If Equipped
(*)
F73 20 Amp Blue –PWR TOP LT
(*)
F74 20 Amp Blue –PWR TOP RT
(*)
F75 –10 Amp Red Power Pack Unit - Battery Pack Control Module & Auxiliary
Power Module (PPU-BPCM & APM) Belt Starter Generator
(BSG) — If Equipped
(*)
F76 –20 Amp Yellow ECM (GAS)/PCM (DSL)
(*)
F77 –10 Amp Red HTD MIRRORS
F78 –10 Amp Red COMP/INTRUSION/SIREN/INTRUSION SENSORS
F79 –20 Amp Yellow SMART BAR CTRL MOD
(*)
F80 –15 Amp Blue Powertrain Control Module (PCM)
(*)
F81 30 Amp Pink –REAR DEFROSTER (EBL)
Cavity Cartridge Fuse Micro Fuse Description
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210
SERVICING AND MAINTENANCE
SCHEDULED SERVICING
Correct servicing is crucial for guaranteeing a
long life for the car under the best condi-
tions. For this reason, Jeep has planned a
series of checks and services at fixed
distance intervals and, where provided, at
fixed time intervals, as described in the
Scheduled Servicing plan. To keep the car’s
efficiency in tip-top condition, in the
following Scheduled Service plan pages a
few additional checks are listed that should
be carried out more frequently with respect
to the normal coupon redemption schedule.
Scheduled Servicing is offered by all autho -
rized dealerships according to fixed time or
mileage intervals. If, during each operation,
in addition to the ones scheduled, the need
arises for further replacements or repairs,
these may be carried out with the owner's
explicit agreement only.
The technicians at your dealership know your
vehicle best, and have access to factory
trained information, genuine Mopar parts,
and specially designed electronic and
mechanical tools that can help prevent
future costly repairs. If your car is used
frequently for towing, the interval between
one scheduled servicing operation and the next should be reduced. More frequent main
-
tenance may be needed for vehicles in severe
operating conditions, such as dusty areas
and very short trip driving.
NOTE:
Scheduled Servicing interventions are set
out by the Manufacturer. Failure to have
them carried out may invalidate the
warranty. It is advised to inform an autho -
rized dealership of any small operating irreg -
ularities without waiting for the next service.
Scheduled Servicing — Gasoline Engine
The oil change indicator system (if
equipped) will remind you that it is time to
take your vehicle in for engine oil replace -
ment.
On vehicles equipped with instrument
cluster display, “Oil Change Required” will
be displayed and a single chime will sound,
indicating that an oil change is necessary.
On non-instrument cluster display equipped
vehicles, “Change Oil” will flash in the
instrument cluster odometer and a single
chime will sound, indicating that an oil
change is necessary. The oil change indicator message will illumi
-
nate approximately 7,000 miles
(11,200 km) after the most recent oil
change was performed. Have your vehicle
serviced as soon as possible, within
500 miles (800 km). However, an earlier oil
change at 4,500 miles (7,500 km) may be
required if the vehicle is operated under
“Severe Duty Conditions” later in this
section.
NOTE:
The oil change indicator message will not
monitor the time since the last oil change.
Change your vehicle's oil if it has been
12 months since your last oil change even
if the oil change indicator message is NOT
illuminated.
Change your engine oil more often if you
drive your vehicle off-road for an extended
period of time.
Under no circumstances should oil change
intervals exceed 7,500 miles
(12,000 km) or 12 months, whichever
comes first.
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change.
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