2018 JEEP WRANGLER UNLIMITED oil temperature

into NEUTRAL and idle the vehicle. If the
temperature reading does not return to nor-
mal, 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 and 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 unbuck-
led, 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 corresponding to the
specific seat will turn on in the upper right
portion of the instrument cluster display, mo-
mentarily replacing the configurable corner
information. If a second row seat belt that
was buckled at the start of the trip is unbuck-
led, 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.
— 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
69

vehicle and run the engine at idle or slightly
faster, with the transmission in PARK or
NEUTRAL, until the light turns off. Once the
light turns off, you may continue to drive
normally.
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.
— 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 Warn-
ing 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 in-
spected 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.
• The “ESC Off Indicator Light” and the
“ESC Indicator Light” come on momen-
tarily each time the ignition is placed in the
ON/RUN or ACC/ON/RUN position.
GETTING TO KNOW YOUR INSTRUMENT PANEL
70

ALWAYS DO A VISUAL CHECKthat 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.
Normal Starting — Diesel Engine
1. The gear selector must be in the NEU-
TRAL 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. Tip Start Feature
Do notpress the accelerator. Cycle the
ignition 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 disengageautomatically in 25 seconds. If this oc-
curs, cycle the ignition to the LOCK posi-
tion, wait 25 to 30 seconds, 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 cycling the ignition to the
OFF position, if required.
5. 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
nozzles. Also, the unburned fuel can enter
the crankcase, diluting the oil and causing
rapid wear to the engine.
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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 theengine three to five minutes before shutting it
down. 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
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.
STARTING AND OPERATING
146

**** The spark plug change interval is mile-
age based only, yearly intervals do not apply.
***** This maintenance is recommended by
the manufacturer to the owner, but is not
required to maintain emissions warranty.
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 com-
petent 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.
Severe Duty Conditions
Change the engine oil and engine oil filter at
every 4500 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 (commercial
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 dis-
played and a single chime will sound, indi-
cating that an oil change is necessary.
On non-instrument cluster display equipped
vehicles, “Change Oil” will flash in the instru-
ment 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 fre-
quent 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 instru-
ment cluster. In any case, it must never ex-
ceed two years. If the vehicle is used mainly
for city driving, change the engine oil and
filter every year.
•Flush and replace the engine coolant at
120 months or 150,000 miles (240,000 km)
whichever comes first.
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•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.
Once A Month Or Before A Long Trip
• Check engine oil level.
• Check windshield washer fluid level.
• Check tire pressure and look for unusual
wear or damage. Rotate tires at the first
sign of irregular wear, even if it occurs
before the oil indicator system turns on.
• Check the fluid levels of the coolant reser-
voir and brake master cylinder, fill as
needed.
• Check function of all interior and exterior
lights.
• Control and recovery of additive level for
AdBlue Diesel emissions (UREA) (if
equipped).Demanding Vehicle Use
• Restore additive level for AdBlue Diesel
emissions (UREA) (if equipped), when the
lamp is illuminated or the message on the
instrument panel.
CAUTION!
Failure to perform the required mainte-
nance items may result in damage to the
vehicle.
Maintenance Plan — Diesel Engine
Required Maintenance Intervals
Refer to the maintenance plan on the follow-
ing pages for the required maintenance inter-
vals.
At Every Oil Change Interval As Indicated By Oil
Change Indicator System:
•
Change oil and filter
•
Rotate the tires
Rotate at the first sign of irregular wear, even
if it occurs before the oil indicator system
turns on
At Every Oil Change Interval As Indicated By Oil
Change Indicator System:
• Inspect battery and clean and tighten ter-
minals as required
• Inspect brake pads, shoes, rotors, drums,
hoses and park brake
• Inspect engine cooling system protection
and hoses
•
Inspect exhaust system
• Inspect engine air cleaner if using in dusty
or off-road conditions
• Inspect all door latches for presence of
grease, reapply if necessary.
•
Inspect coolant level.
NOTE:
Once you have carried out the last interven-
tion in the table, continue with the scheduled
servicing, maintaining the frequency indi-
cated in the plan by marking each operation
with a dot or dedicated note. Simply restart-
ing the maintenance from the start of the
plan may cause the allowed interval to be
exceeded for some operations.SERVICING AND MAINTENANCE
214

Mileage or time passed (whichever comes first)12,500
25,000
37,500
50,000
62,500
75,000
87,500
100,000
112,500
125,000
137,500
150,000
162,500
175,000
187,500
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
180,000
200,000
220,000
240,000
260,000
280,000
300,000
Flush and replace the engine coolant at 10 years or
150,000 miles (240,000 km) whichever comes first.XX
Replace timing drive belt. (***) X X
(*) 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 instru-
ment cluster. In any case, it must never
exceed two years. If the vehicle is used
mainly for city driving, change the engine oil
and filter every year.
(**) The brake fluid interval is time based
only, mileage intervals do not apply.
(***) 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 orvery high temperatures for extended periods,
city driving, long periods of idling). Under no
circumstances should these intervals be ex-
ceeded.
(°) Consumption of additive AdBlue (UREA)
depends on the condition of use of the ve-
hicle 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
WARNING!
service job, take your vehicle to a com-
petent 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.
SERVICING AND MAINTENANCE
216

Checking Oil Level — Gasoline Engine
WARNING!
• Never smoke while working in the engine
compartment: gas and inflammable va-
pors 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 se-
verely 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.
CAUTION!
• If the engine oil is being topped up, wait
for the engine to cool down before loos-
ening the filler cap, particularly for ve-
hicles with aluminium cap (if
equipped). WARNING: risk of burns!
• Overfilling or underfilling the crankcase
will cause aeration or loss of oil pres-
sure. This could damage your 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 reser-
voir 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 perfor-
mance.
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 rat-
ing information can be found on most washer
fluid containers.
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.
SERVICING AND MAINTENANCE
220