service JEEP WRANGLER UNLIMITED 2020 Owner handbook (in English)

SERVICING AND MAINTENANCE
230(Continued)
Coolant Checks
Check the engine and, intercooler (if
equipped) coolant (antifreeze) protection
every 12 months (before the onset of
freezing weather, where applicable). If the
engine and, intercooler (if equipped) is dirty
or rusty in appearance, the system should be
drained, flushed and refilled with fresh OAT
coolant (conforming to MS.90032) by an
authorized dealer. Check the front of the A/C
condenser (if equipped) or radiator for any
accumulation of bugs, leaves, etc. If dirty,
clean by gently spraying water from a garden
hose vertically down the face of the A/C
condenser (if equipped) or the back of the
radiator core.Check the engine and, intercooler (if
equipped) cooling system hoses for brittle
rubber, cracking, tears, cuts, and tightness
of the connection at the coolant recovery
bottle and radiator. Inspect the entire system
for leaks. DO NOT REMOVE THE COOLANT
PRESSURE CAP WHEN THE COOLING
SYSTEM IS HOT.
Brake System
In order to ensure brake system perfor
-
mance, all brake system components should
be inspected periodically. Refer to the
“Maintenance Plan” in this section for the
proper maintenance intervals.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should
be checked whenever the vehicle is serviced,
or immediately if the brake system warning
light is on. If necessary, add fluid to bring
level within the designated marks on the side
of the reservoir of the brake master cylinder.
Be sure to clean the top of the master
cylinder area before removing cap. With disc
brakes, fluid level can be expected to fall as
the brake pads wear. Brake fluid level should
be checked when pads are replaced. If the
brake fluid is abnormally low, check the
system for leaks.
Refer to “Fluids And Lubricants” in “Tech -
nical Specifications” for further information.When working near the radiator cooling
fan, turn the ignition to the OFF mode.
The fan is temperature controlled and
can start at any time the ignition is in the
ON mode.
WARNING! (Continued)
WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your
foot resting or riding on the brake pedal
can result in abnormally high brake
temperatures, excessive lining wear, and
possible brake damage. You would not
have your full braking capacity in an
emergency. WARNING!
Use only manufacturer's recommended
brake fluid. Refer to “Fluids And Lubri -
cants” in “Technical Specifications” for
further information. Using the wrong
type of brake fluid can severely damage
your brake system and/or impair its
performance. The proper type of brake
fluid for your vehicle is also identified on
the original factory installed hydraulic
master cylinder reservoir.
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SERVICING AND MAINTENANCE
232
(Continued)
Fluid Level Check
The fluid level is preset at the factory and
does not require adjustment under normal
operating conditions. Routine fluid level
checks are not required; therefore the trans-
mission has no dipstick. An authorized
dealer can check your transmission fluid
level using special service tools. If you notice
fluid leakage or transmission malfunction,
visit an authorized dealer immediately to
have the transmission fluid level checked.
Operating the vehicle with an improper fluid
level can cause severe transmission damage.
RAISING THE VEHICLE
In the case where it is necessary to raise the
vehicle, go to an authorized dealer or service
station.
TIRES
Tires — General Information
Tire Pressure
Proper tire inflation pressure is essential to
the safe and satisfactory operation of your
vehicle. Four primary areas are affected by
improper tire pressure:
Safety
Fuel Economy
Tread Wear
Ride Comfort and Vehicle Stability
Safety Both underinflation and overinflation affect
the stability of the vehicle and can produce
a feeling of sluggish response or over respon
-
siveness in the steering.
NOTE:
Unequal tire pressures from side to side
may cause erratic and unpredictable
steering response.
Unequal tire pressure from side to side
may cause the vehicle to drift left or right.
Fuel Economy

Underinflated tires will increase tire rolling
resistance resulting in higher fuel consumption.

CAUTION!
If a transmission fluid leak occurs, visit an
authorized dealer immediately. Severe
transmission damage may occur. An
authorized dealer has the proper tools to
adjust the fluid level accurately.
WARNING!
Improperly inflated tires are dangerous
and can cause collisions.
Underinflation increases tire flexing and
can result in overheating and tire failure.
Overinflation reduces a tire's ability to
cushion shock. Objects on the road and
chuckholes can cause damage that
result in tire failure.

Overinflated or underinflated tires can affect
vehicle handling and can fail suddenly,
resulting in loss of vehicle control.

Unequal tire pressures can cause
steering problems. You could lose
control of your vehicle.
Unequal tire pressures from one side of
the vehicle to the other can cause the
vehicle to drift to the right or left.

Always drive with each tire inflated to the
recommended cold tire inflation pressure.

WARNING! (Continued)
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SERVICING AND MAINTENANCE
234
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe
speeds and within posted speed limits.
Where speed limits or conditions are such
that the vehicle can be driven at high speeds,
maintaining correct tire inflation pressure is
very important. Increased tire pressure and
reduced vehicle loading may be required for
high-speed vehicle operation. Refer to an
authorized tire dealer or original equipment
vehicle dealer for recommended safe oper-
ating speeds, loading and cold tire inflation
pressures.
Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be
repaired if it meets the following criteria:
The tire has not been driven on when flat.

The damage is only on the tread section of
your tire (sidewall damage is not repairable).

The puncture is no greater than a ¼ of an
inch (6 mm).
Consult an authorized tire dealer for tire
repairs and additional information.
Damaged Run Flat tires, or Run Flat tires
that have experienced a loss of pressure
should be replaced immediately with another
Run Flat tire of identical size and service
description (Load Index and Speed Symbol).
Replace the tire pressure sensor as well as it
is not designed to be reused.
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to
drive 50 miles (80 km) at 50 mph (80 km/h)
after a rapid loss of inflation pressure. This
rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs
when the tire inflation pressure is of/or below
14 psi (96 kPa). Once a Run Flat tire reaches
the run flat mode it has limited driving capa -
bilities and needs to be replaced immedi -
ately. A Run Flat tire is not repairable. When
a run flat tire is changed after driving with
underinflated tire condition, please replace
the TPM sensor as it is not designed to be
reused when driven under run flat mode 14
psi (96 kPa) condition.
NOTE:
TPM Sensor must be replaced after driving
the vehicle on a flat tire condition.
It is not recommended driving a vehicle
loaded at full capacity or to tow a trailer
while a tire is in the run flat mode.
See the tire pressure monitoring section for
more information.
WARNING!
High speed driving with your vehicle under
maximum load is dangerous. The added
strain on your tires could cause them to
fail. You could have a serious collision. Do
not drive a vehicle loaded to the maximum
capacity at continuous speeds above
75 mph (120 km/h).
WARNING!
Combining radial ply tires with other types
of tires on your vehicle will cause your
vehicle to handle poorly. The instability
could cause a collision. Always use radial
ply tires in sets of four. Never combine
them with other types of tires.
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235
Tire Spinning
When stuck in mud, sand, snow, or ice
conditions, do not spin your vehicle's wheels
above 30 mph (48 km/h) or for longer than
30 seconds continuously without stopping.
Refer to “Freeing A Stuck Vehicle” in “In
Case Of Emergency” for further information.
Tread Wear Indicators
Tread wear indicators are in the original
equipment tires to help you in determining
when your tires should be replaced.Tire Tread
These indicators are molded into the bottom
of the tread grooves. They will appear as
bands when the tread depth becomes a 1/16
of an inch (1.6 mm). When the tread is worn
to the tread wear indicators, the tire should
be replaced.
Refer to “Replacement Tires” in this section
for further information.
Life Of Tire
The service life of a tire is dependent upon
varying factors including, but not limited to:
Driving style
Tire pressure - Improper cold tire inflation
pressures can cause uneven wear patterns
to develop across the tire tread. These
abnormal wear patterns will reduce tread
life, resulting in the need for earlier tire
replacement
Distance driven
Performance tires, tires with a speed
rating of V or higher, and Summer tires
typically have a reduced tread life. Rota-
tion of these tires per the vehicle sched -
uled maintenance is highly recommended
WARNING!
Fast spinning tires can be dangerous.
Forces generated by excessive wheel
speeds may cause tire damage or failure. A
tire could explode and injure someone. Do
not spin your vehicle's wheels faster than
30 mph (48 km/h) for more than 30
seconds continuously when you are stuck,
and do not let anyone near a spinning
wheel, no matter what the speed.1 — Worn Tire
2 — New Tire
WARNING!
Tires and the spare tire should be replaced
after six years, regardless of the remaining
tread. Failure to follow this warning can
result in sudden tire failure. You could lose
control and have a collision resulting in
serious injury or death.
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237
Tire Types
All Season Tires — If Equipped
All Season tires provide traction for all
seasons (Spring, Summer, Autumn, and
Winter). Traction levels may vary between
different all season tires. All season tires can
be identified by the M+S, M&S, M/S or MS
designation on the tire sidewall. Use all
season tires only in sets of four; failure to do
so may adversely affect the safety and
handling of your vehicle.

Summer Or Three Season Tires — If Equipped

Summer tires provide traction in both wet
and dry conditions, and are not intended to
be driven in snow or on ice. If your vehicle is
equipped with Summer tires, be aware these
tires are not designed for Winter or cold
driving conditions. Install Winter tires on
your vehicle when ambient temperatures are
less than 40°F (5°C) or if roads are covered
with ice or snow. For more information,
contact an authorized dealer.

Summer tires do not contain the all season desig-
nation or mountain/snowflake symbol on the tire
sidewall. Use Summer tires only in sets of four;
failure to do so may adversely affect the safety
and handling of your vehicle.

Snow Tires
Some areas of the country require the use of
snow tires during the Winter. Snow tires can
be identified by a “mountain/snowflake”
symbol on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the
original equipment tires. Use snow
tires only in sets of four; failure to
do so may adversely affect the safety and
handling of your vehicle.
Snow tires generally have lower speed ratings
than what was originally equipped with your
vehicle and should not be operated at
sustained speeds over 75 mph (120 km/h).
For speeds above 75 mph (120 km/h) refer
to original equipment or an authorized tire
dealer for recommended safe operating
speeds, loading and cold tire inflation pres -
sures. While studded tires improve performance on
ice, skid and traction capability on wet or dry
surfaces may be poorer than that of
non-studded tires. Some states prohibit
studded tires; therefore, local laws should be
checked before using these tire types.
Spare Tires — If Equipped
NOTE:
For vehicles equipped with Tire Service Kit
instead of a spare tire, please refer to “Tire
Service Kit” in “In Case Of Emergency” in
the Owner’s Manual for further information.
Refer to the “Towing Requirements - Tires”
in “Starting And Operating” in the Owner’s
Manual for restrictions when towing with a
spare tire designated for temporary emer
-
gency use.
WARNING!
Do not use Summer tires in snow/ice
conditions. You could lose vehicle control,
resulting in severe injury or death. Driving
too fast for conditions also creates the
possibility of loss of vehicle control.
CAUTION!
Because of the reduced ground clearance,
do not take your vehicle through an
automatic car wash with a compact or
limited use temporary spare installed.
Damage to the vehicle may result.
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SERVICING AND MAINTENANCE
242
If you are storing your vehicle for more than
21 days, we recommend that you take the
following steps to minimize the drain on your
vehicle's battery:
Disconnect the negative cable from
battery.
If your vehicle is equipped with Stop/Start
system then disconnect both the main and
supplemental negative battery cables.
Any time you store your vehicle or keep it
out of service (i.e., vacation) for two weeks
or more, run the air conditioning system at
idle for about five minutes in the fresh air
and high blower setting. This will ensure
adequate system lubrication to minimize
the possibility of compressor damage
when the system is started again.
If assistance is needed to disconnect the
battery system, see your authorized dealer.Battery Cable Disconnect
NOTE:
You must isolate the supplemental battery
connection point, as well as the main
battery terminal from the post, as shown in
the image, to fully de-energize both
batteries for storage. If assistance is
needed to disconnect the battery system,
see an authorized dealer.
Do not disconnect the Intelligent Battery
Sensor (IBS), or your Stop/Start system
may not function for up to 24 hours, due
to the IBS being set into learn mode.
BODYWORK
Body And Underbody Maintenance
Cleaning Headlights
Your vehicle is equipped with plastic head -
lights and fog lights that are lighter and less
susceptible to stone breakage than glass
headlights.
Plastic is not as scratch resistant as glass
and therefore different lens cleaning proce -
dures must be followed.
To minimize the possibility of scratching the
lenses and reducing light output, avoid
wiping with a dry cloth. To remove road dirt,
wash with a mild soap solution followed by
rinsing.
Do not use abrasive cleaning components,
solvents, steel wool or other aggressive mate -
rial to clean the lenses.
CAUTION!
If the negative battery cables are not
isolated properly it can cause a potential
power spike or surge in the system,
resulting in damage to essential electrical
components.
1 — Supplemental Negative Battery Cable
2 — Main Negative Battery Cable
3 — Intelligent Battery Sensor (IBS)
4 — Main Negative Battery Terminal
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TECHNICAL SPECIFICATIONS
248
Tighten the lug nuts/bolts in a star pattern
until each nut/bolt has been tightened twice.
Ensure that the socket is fully engaged on
the lug nut/bolt (do not insert it halfway).Torque Patterns
After 25 miles (40 km), check the lug nut/
bolt torque to be sure that all the lug nuts/
bolts are properly seated against the wheel.WHEELS
Refer to the tire placard label located on the
door sill of the vehicle or to the Registration
Document for the tire size and pressure.
Refer to “Tires” in “Servicing And Mainte -
nance” chapter for further information.
WEIGHTS
For further information refer to “Vehicle
Loading” in the “Starting And Operating”
chapter.
FUEL REQUIREMENTS —
GASOLINE ENGINE
2.0L Engine
This engine is designed to meet all emission
regulations, and provide satisfactory fuel
economy and performance when using
high-quality unleaded gasoline with a recom -
mended RON of 95.
While operating on gasoline with the
required octane number, hearing a light
knocking sound from the engine is not a
cause for concern. However, if the engine is
heard making a heavy knocking sound, see
your dealer immediately. Use of gasoline
with a lower than recommended octane
number can cause engine failure and may
void or not be covered by the New Vehicle
Limited Warranty.
Poor quality gasoline can cause problems
such as hard starting, stalling, and hesita -
tions. If you experience these symptoms, try
another brand of gasoline before considering
service for the vehicle.
WARNING!
To avoid the risk of forcing the vehicle off
the jack, do not tighten the lug nuts/bolts
fully until the vehicle has been lowered.
Failure to follow this warning may result in
personal injury.
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249
3.6L Engine
This engine is designed to meet all emissions
regulations and provide excellent fuel
economy and performance when using
high-quality unleaded gasoline with a
minimum Research Octane Number (RON)
of 91.
Light spark knock at low engine speeds is not
harmful to your engine. However, continued
heavy spark knock at high speeds can cause
damage, and immediate service is required.
Poor quality gasoline can cause problems
such as hard starting, stalling, and hesita-
tions. If you experience these symptoms, try
another brand of gasoline before considering
service for the vehicle. Besides using unleaded gasoline with the
proper octane rating, gasolines that contain
detergents, corrosion and stability additives
are recommended. Using gasolines that have
these additives may help improve fuel
economy, reduce emissions, and maintain
vehicle performance.
Poor quality gasoline can cause problems
such as hard starting, stalling, and hesita
-
tions. If you experience these symptoms, try
another brand of gasoline before considering
service for the vehicle.
Materials Added To Fuel
Indiscriminate use of fuel system cleaning
agents should be avoided. Many of these
materials intended for gum and varnish
removal may contain active solvents or
similar ingredients. These can harm fuel
system gasket and diaphragm materials.
Fuel Icon Identification Compliant To
EN16942
The following symbols make it easier to
recognize the correct type of fuel to be used
on your vehicle. Before proceeding with the
supply, check the symbols placed inside the
fuel filler flap (if present) and compare them
with the symbol on the fuel pump (if
present).
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MULTIMEDIA
264
Loudness — If Equipped
Press the On button on the touchscreen to
activate Loudness. Press the Off button to
deactivate this feature. When Loudness is
On, the sound quality at lower volumes
improves.
AUX Volume Offset
Press the AUX Volume Offset button on
the touchscreen to activate the AUX
Volume Offset screen. The AUX Volume
Offset is adjusted by pressing the + and –
buttons. This alters the AUX input audio
volume. The level value, which spans
between plus or minus three, is displayed
above the adjustment bar.
Auto Play
Press the Auto Play button on the touch -
screen to activate the Auto Play screen.
The Auto Play feature has two settings
“On” and “Off”. With Auto Play On, music
begins playing from a connected device,
immediately after it is connected to the
radio. Auto On Radio — If Equipped
The Radio turns on always when the igni
-
tion is ON/RUN regardless if the radio was
turned Off or On in the last ignition Off
state OR will recall whether it was On or
Off at the last ignition state.
Radio Off With Door — If Equipped
Press the Radio Off With Door button on
the touchscreen to activate the Radio Off
With Door screen. The Radio Off With Door
feature, when activated, keeps the radio
on until the driver or passenger door is
opened or when the Radio Off Delay
selected time has expired.
Drag & Drop Menu Bar
The Uconnect features and services in the
main menu bar are easily changed for your
convenience. Simply follow these steps:
Uconnect 4 Main Menu
1. Press the Apps button to open the App screen.
2. Press and hold, then drag the selected App to replace an existing shortcut in the
main menu bar.
The new app shortcut, that was dragged
down onto the main menu bar, will now be an
active App/shortcut.
NOTE:
This feature is only available if the vehicle is
in PARK (P).
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269
Press + or – next to “Set Time Hours” and
“Set Time Minutes” to adjust the time.
If these features are not available,
uncheck the “Sync Time” box.
Press X to save your settings and exit out
of the Clock Setting screen.
Background Themes
Screen background themes are selectable
from a preloaded list of themes. If you’d like
to set a theme, follow the instructions below.
1. Press the Settings button on the touch -
screen and select the display menu.
2. Press the Set Theme button on the touchscreen and select a theme.
Audio Settings
Press the Audio button on the touchscreen
to activate the Audio settings screen to
adjust Balance\Fade, Equalizer, and
Speed Adjusted Volume.
You can return to the Radio screen by
pressing the X located at the top right. Balance/Fade
Press the Balance/Fade button on the
touchscreen to Balance audio between the
front speakers or fade the audio between
the rear and front speakers.
Pressing the Front, Rear, Left, or Right
buttons on the touchscreen or press and
drag the Speaker Icon to adjust the
Balance/Fade.
Equalizer
Press the Equalizer button on the touch -
screen to activate the Equalizer screen.
Press the + or – buttons on the touch -
screen, or press and drag over the level bar
for each of the equalizer bands. The level
value, which spans between plus or minus
nine, is displayed at the bottom of each of
the Bands.
Speed Adjusted Volume
Press the Speed Adjusted Volume button
on the touchscreen to activate the Speed
Adjusted Volume screen. The Speed
Adjusted Volume is adjusted by pressing
the volume level indicator. This alters the
automatic adjustment of the audio volume
with variation to vehicle speed.
Drag & Drop Menu Bar
The Uconnect features and services in the
main menu bar are easily changed for your
convenience. Simply follow these steps:
1. Press the Apps button to open the App screen.
2. Press and hold, then drag the selected App to replace an existing shortcut in the
main menu bar.
The new app shortcut, that was dragged
down onto the main menu bar, will now
be an active App/shortcut.
NOTE:
This feature is only available if the vehicle is
in PARK.
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