2020 JEEP WRANGLER UNLIMITED oil temperature

67
— Engine Coolant Temperature Warning
Light
This warning light warns of an overheated
engine condition. If the engine coolant
temperature is too high, this indicator will
illuminate and a single chime will sound. If
the temperature reaches the upper limit, a
continuous chime will sound for four
minutes or until the engine is able to cool;
whichever comes first.
If the light turns on while driving, safely pull
over and stop the vehicle. If the A/C system
is on, turn it off. Also, shift the transmission
into Park and allow the vehicle to sit idle
(propulsion system active). If the tempera -
ture reading does not return to normal, turn
the engine off immediately and call for
service.
Refer to “If Your Engine Overheats” in “In
Case Of Emergency” for further information.
— Hood Open Warning Light
This indicator will illuminate when the hood
is ajar/open or not fully closed.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Oil Pressure Warning Light
This warning light will illuminate to indicate
low engine oil pressure. If the light turns on
while driving, stop the vehicle, shut off the
engine as soon as possible, and contact an
authorized dealer. A chime will sound when
this light turns on.
Do not operate the vehicle until the cause is
corrected. This light does not indicate how
much oil is in the engine. The engine oil level
must be checked under the hood.
— Oil Temperature Warning Light
This warning light will illuminate to indicate
the engine oil temperature is high. If the
light turns on while driving, stop the vehicle
and shut off the engine as soon as possible.
Wait for oil temperature to return to normal
levels.
— Seat Belt Reminder Warning Light
This warning light indicates when the driver
or passenger seat belt is unbuckled. When
the ignition is first placed in the ON/RUN or
ACC/ON/RUN position and if the driver’s
seat belt is unbuckled, a chime will sound
and the light will turn on. When driving, if the driver or front passenger seat belt
remains unbuckled, the Seat Belt Reminder
Light will flash or remain on continuously
and a chime will sound.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
— Rear Seat Belt Reminder Warning Light
— If Equipped
This light indicates when a rear seat belt is
unbuckled in the second row. When the igni -
tion is first placed in the ON/RUN or ACC/
ON/RUN position, and if a seat belt in the
second row is unbuckled, a light corre -
sponding to the specific seat will turn on in
the upper right portion of the instrument
cluster display, momentarily replacing the
configurable corner information. If a second
row seat belt that was buckled at the start of
the trip is unbuckled, the Rear Seat Belt
Reminder Light will change from green to red
and a single chime will sound.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
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GETTING TO KNOW YOUR INSTRUMENT PANEL
68
— Swing Gate Open Warning Light
This warning light will illuminate when the
swing gate is open.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Transmission Temperature Warning
Light — If Equipped
This warning light will illuminate to warn of
a high transmission fluid temperature. This
may occur with strenuous usage such as
trailer towing. If this light turns on, stop the
vehicle and shift the transmission into Park
and allow the vehicle to sit idle (propulsion
system active), until the light turns off. Once
the light turns off, you may continue to drive
normally.
— Vehicle Security Warning Light — If
Equipped
This light will flash at a fast rate for approxi -
mately 15 seconds when the vehicle security
alarm is arming, and then will flash slowly
until the vehicle is disarmed.
Yellow Warning Lights
— Anti-Lock Brake (ABS) Warning Light
This warning light monitors the Anti-Lock
Brake System (ABS). The light will turn on
when the ignition is placed in the ON/RUN or
ACC/ON/RUN position and may stay on for as
long as four seconds.
If the ABS light remains on or turns on while
driving, then the Anti-Lock portion of the
brake system is not functioning and service
is required as soon as possible. However, the conventional brake system will continue to
operate normally, assuming the Brake
Warning Light is not also on.
If the ABS light does not turn on when the
ignition is placed in the ON/RUN or ACC/ON/
RUN position, have the brake system
inspected by an authorized dealer.
— Electronic Stability Control (ESC)
Active Warning Light — If Equipped
This warning light will indicate when the
Electronic Stability Control system is Active.
The “ESC Indicator Light” in the instrument
cluster will come on when the ignition is
placed in the ON/RUN or ACC/ON/RUN posi -
tion, and when ESC is activated. It should go
out with the engine running. If the “ESC
Indicator Light” comes on continuously with
the engine running, a malfunction has been
detected in the ESC system. If this warning
light remains on after several ignition cycles,
and the vehicle has been driven several miles
(kilometers) at speeds greater than 30 mph
(48 km/h), see an authorized dealer as soon
as possible to have the problem diagnosed
and corrected.
WARNING!
If you continue operating the vehicle when
the Transmission Temperature Warning
Light is illuminated you could cause the
fluid to boil over, come in contact with hot
engine or exhaust components and cause a
fire.
CAUTION!
Continuous driving with the Transmission
Temperature Warning Light illuminated
will eventually cause severe transmission
damage or transmission failure.
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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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SERVICING AND MAINTENANCE
216
Severe Duty Conditions
Change the engine oil and engine oil filter at
every 4,500 miles (7,500 km) or 6 months
if using your vehicle under any of the
following severe duty conditions:
Stop and go driving.
Driving in dusty conditions.
Short trips of less than 10 miles (16 km).
Trailer towing.
Taxi, police, or delivery service (commer-
cial service).
Off-road or desert operation.
Scheduled Servicing — Diesel Engine
Your vehicle is equipped with an automatic
oil change indicator system. The oil change
indicator system will remind you that it is
time to take your vehicle in for engine oil
replacement.
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.

Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures will influence when the
“Oil Change Required” message is displayed. Severe Operating Conditions can cause the
change oil message to illuminate as earlier than
specified. Have your vehicle serviced as soon
as possible, within the next 500 miles
(805 km).

NOTE:
The actual interval for changing engine oil
and replacing the engine oil filter depends
on the vehicle usage conditions, and is
signaled by the warning light or message
in the instrument panel. In any case, it
must never exceed 12,500 miles
(20,000 km) or 1 year
Flush and replace the engine coolant at
120 months or 150,000 miles (240,000 km)
whichever comes first.
The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance trav-
eled. The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use
(dusty areas, severe weather conditions,
very low or very high temperatures for
extended periods, city driving, long periods
of idling). Under no circumstances should
these intervals be exceeded.
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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SERVICING AND MAINTENANCE
220
(*) The actual interval for changing engine
oil and replacing the engine oil filter
depends on the vehicle usage conditions,
and is signaled by the warning light or
message in the instrument panel. In any
case, it must never exceed 12,500 miles
(20,000 km) or 1 year.
(**) The brake fluid interval is time based
only, mileage intervals do not apply.(***) The maximum mileage is 75,000 mi
(120,000 km). The belt must be replaced
every 5 years regardless of distance traveled.
The timing and accessory belts must be
changed every 37,500 miles (60,000 km) or
3 years for particularly demanding use (dusty
areas, severe weather conditions, very low or
very high temperatures for extended periods,
city driving, long periods of idling). Under no
circumstances should these intervals be
exceeded.
(°) Consumption of additive AdBlue®
(UREA) depends on the condition of use of
the vehicle and is indicated by LED and/or
message on the instrument panel. WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge
and the right equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe-
tent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an
accident.
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SERVICING AND MAINTENANCE
224
(Continued)
Checking Oil Level — Gasoline Engine
To ensure proper lubrication of your vehicle's
engine, the engine oil must be maintained at
the correct level. The engine oil level should
be checked five minutes after a warmed up
engine has been shut off.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil
level readings. Always maintain the oil level
within the SAFE zone on the dipstick. Adding
1 quart (0.95 liters) of oil when the reading
is at the bottom of the crosshatch zone will
result in a reading at the top of the cross-
hatch zone on these engines.
Adding Washer Fluid
The fluid reservoir for the windshield
washers and the rear window washer (if
equipped) is shared. The fluid reservoir is
located in the engine compartment. Be sure
to check the fluid level at regular intervals.
Fill the reservoir with windshield washer
solvent only (not radiator antifreeze). When
refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel
and wipe clean the wiper blades; this will
help blade performance.
To prevent freeze-up of your windshield
washer system in cold weather, select a solu -
tion or mixture that meets or exceeds the
temperature range of your climate. This
rating information can be found on most
washer fluid containers. WARNING!

Never smoke while working in the engine
compartment: gas and inflammable vapors
may be present, with the risk of fire.

Be very careful when working in the
engine compartment when the engine is
hot: you may get burned. Do not get too
close to the radiator cooling fan: the
electric fan may start; danger of injury.
Scarves, ties and other loose clothing
might be pulled by moving parts.
CAUTION!
Be careful not to confuse the various
types of fluids while topping up: they are
not compatible with each other! Topping
up with an unsuitable fluid could
severely damage your car.
The oil level must never exceed the MAX
mark.
Always top up using engine oil of the
same specifications as that already in
the engine.
If the engine oil is being topped up, wait
for the engine to cool down before loos-
ening the filler cap, particularly for vehi -
cles with aluminium cap (if equipped).
WARNING: risk of burns!
Overfilling or underfilling the crankcase
will cause aeration or loss of oil pressure.
This could damage your engine.
CAUTION! (Continued)
WARNING!
Commercial windshield washer solvents
are flammable. They could ignite and burn
you. Care must be exercised when filling or
working around the washer solution.
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279
Pitch & Roll
The Pitch & Roll page displays the vehicle’s
current pitch (angle up and down) and roll
(angle side to side) in degrees. The pitch and
roll gauges provide a visualization of the
current vehicle angle.Pitch & Roll Menu 2WD/4WD
Accessory Gauge
The Accessory Gauge page displays the
current status of the vehicle’s Coolant
Temperature, Oil Temperature, Oil Pressure
(Gas Vehicles Only), Transmission Tempera -
ture, and Battery Voltage.
Accessory Gauges Menu 2WD/4WD
STEERING WHEEL AUDIO
CONTROLS
The remote sound system controls are
located on the rear surface of the steering
wheel. Reach behind the wheel to access the
switches.Audio Controls (Back View Of Steering Wheel)
The right-hand control is a rocker-type
switch with a push-button in the center and
controls the volume and mode of the sound
system. Pushing the top of the rocker switch
increases the volume, and pushing the
bottom of the rocker switch decreases the
volume.
Pushing the center button mutes the radio.
1 — Current Pitch
2 — Current Roll
1 — Coolant Temperature
2 — Oil Temperature
3 — Oil Pressure (Gas Vehicles Only)
4 — Battery Voltage
5 — Transmission Temperature (Automatic
Transmissions Only)
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