warning JEEP WRANGLER 2021 Owner handbook (in English)

WARNING!
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 follow-
ing 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
At Each Stop for Fuel
• Check the engine oil level about five min-
utes after a fully warmed engine is shut off.
Checking the oil level while the vehicle is
on level ground will improve the accuracy of
the oil level reading. Add oil only when the
level is at or below the ADD or MIN mark.
• Check the windshield washer solvent, add
as required.
Once a Month
• 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.
• Inspect the battery; clean and tighten the
terminals as required.
• Check the fluid levels of engine coolant/
antifreeze deaeration bottle, and brake
master cylinder, add as needed.
• Check all lights and all other electrical
items for correct operation.At Each Oil Change
• Change the engine oil filter.
• Inspect the exhaust system.
• Inspect brake hoses.
• Check the engine coolant/antifreeze level,
hoses, and clamps.
• Inspect engine accessory drive belts. Re-
place as necessary.
• Inspect for the presence of water in the fuel
filter/water separator unit.
Inspection and service should be performed
anytime a malfunction is observed or sus-
pected. Retain all receipts.
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* The actual interval for changing engine oil
and replacing the engine oil filter depends on
the vehicle usage conditions and is signalled
by the warning light or message in the instru-
ment panel. In all cases, never exceed 1 year/
15,000 miles (24,000 km).
** DOT 4 brake fluid is time based only;
mileage intervals do not apply.
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.
179

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.
CAUTION!
Overfilling or underfilling the crankcase
will cause aeration or loss of oil pressure.
This could damage your engine.
Checking Oil Level — Diesel Engine
To assure proper engine lubrication, the en-
gine oil must be maintained at the correct
level. Check the oil level at regular intervals,
such as every fuel stop.For vehicles equipped with a Diesel Particu-
late Filter (DPF), it is acceptable to have an
oil level up to 3/8 inch (10 mm) above the
MAX line. Beyond 3/8 inch (10 mm) it is
recommended to change the oil.
The best time to check the engine oil level is
about five minutes after a fully warmed en-
gine is shut off.
Checking the oil while the vehicle is on level
ground will improve the accuracy of the oil
level readings. Maintain the oil level between
the MIN and MAX markings on the dipstick.
Adding 1 U.S. Quart (0.95 L) of oil when the
reading is at the MIN mark will result in a
MAX reading on these engines.
Cooling System
WARNING!
• You or others can be badly burned by hot
engine coolant (antifreeze) or steam
from your radiator. If you see or hear
steam coming from under the hood, do
not open the hood until the radiator has
had time to cool. Never open a cooling
WARNING!
system pressure cap when the radiator
or coolant bottle is hot.
• Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts auto-
matically and may start at any time,
whether the engine is running or not.
• When working near the radiator cooling
fan, disconnect the fan motor lead or
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.
Engine Coolant Checks
Check the engine coolant (antifreeze) protec-
tion every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant (antifreeze) is dirty or rusty in
appearance, the system should be drained,
flushed and refilled with fresh engine coolant
(antifreeze). Check the front of the A/C con-
denser (if equipped) or radiator for any accu-
mulation of bugs, leaves, etc. If dirty, clean
SERVICING AND MAINTENANCE
182

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 cooling system hoses for
brittle rubber, cracking, tears, cuts, and
tightness of the connection at the coolant
recovery bottle and radiator. Inspect the en-
tire system for leaks. DO NOT REMOVE THE
COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
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 radia-
tor 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 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.
Brake System
In order to assure brake system performance,
all brake system components should be in-
spected periodically. Refer to the “Mainte-
nance Plan” in this section for the proper
maintenance intervals.
WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your
foot resting or riding on the brake pedal
WARNING!
can result in abnormally high brake tem-
peratures, excessive lining wear, and pos-
sible brake damage. You would not have
your full braking capacity in an emergency.
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 cylin-
der 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 sys-
tem for leaks.
Refer to “Fluids And Lubricants” in “Techni-
cal Specifications” for further information.
183

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 per-
formance. The proper type of brake fluid
for your vehicle is also identified on the
original factory installed hydraulic mas-
ter cylinder reservoir.
• To avoid contamination from foreign
matter or moisture, use only new brake
fluid or fluid that has been in a tightly
closed container. Keep the master cylin-
der reservoir cap secured at all times.
Brake fluid in a open container absorbs
moisture from the air resulting in a lower
boiling point. This may cause it to boil
unexpectedly during hard or prolonged
braking, resulting in sudden brake fail-
ure. This could result in a collision.
• Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot en-
gine parts, causing the brake fluid to
WARNING!
catch fire. Brake fluid can also damage
painted and vinyl surfaces, care should
be taken to avoid its contact with these
surfaces.
• Do not allow petroleum based fluid to
contaminate the brake fluid. Brake seal
components could be damaged, causing
partial or complete brake failure. This
could result in a collision.
Manual Transmission
Fluid Level Check
Check the fluid level by removing the fill
plug. The fluid level should be between the
bottom of the fill hole and a point not more
than 3/16 of an inch (4.76 mm) below the
bottom of the hole.
Add fluid, if necessary, to maintain the
proper level.
Automatic Transmission
Fluid Level Check — Gasoline Engine
It is best to check the fluid level when the
transmission is at normal operating tempera-
ture (approximately 180°F/82°C). This oc-
curs after at least 15 miles (25 km) of driv-
ing. At normal operating temperature, the
fluid cannot be held comfortably between the
fingertips.
Use the following procedure to check the
transmission fluid level properly:
1. Park the vehicle on level ground.
2. Remove the engine cover by pulling it up
off the mounting studs (two in the front
and two in the rear).
3. Run the engine at normal idle speed for at
least 60 seconds, and leave the engine
running for the rest of this procedure.
4. Fully apply the parking brake, and press
the brake pedal.
SERVICING AND MAINTENANCE
184

If you notice fluid leakage or transmission
malfunction, visit an authorized dealer im-
mediately to have the transmission fluid level
checked. Operating the vehicle with an im-
proper fluid level can cause severe transmis-
sion damage.
Maintenance-Free Battery
Your vehicle is equipped with a maintenance-
free battery. You will never have to add water,
nor is periodic maintenance required.
WARNING!
• Battery fluid is a corrosive acid solution
and can burn or even blind you. Do not
allow battery fluid to contact your eyes,
skin, or clothing. Do not lean over a
battery when attaching clamps. If acid
splashes in eyes or on skin, flush the
area immediately with large amounts of
water. Refer to “Jump Starting Proce-
dure” in “In Case Of Emergency” for
further information.
• Battery gas is flammable and explosive.
Keep flame or sparks away from the
battery. Do not use a booster battery or
WARNING!
any other booster source with an output
greater than 12 Volts. Do not allow cable
clamps to touch each other.
• Battery posts, terminals, and related ac-
cessories contain lead and lead com-
pounds. Wash hands after handling.
CAUTION!
• It is essential when replacing the cables
on the battery that the positive cable is
attached to the positive post and the
negative cable is attached to the nega-
tive post. Battery posts are marked posi-
tive (+) and negative (-) and are identi-
fied on the battery case. Cable clamps
should be tight on the terminal posts
and free of corrosion.
• If a “fast charger” is used while the
battery is in the vehicle, disconnect both
vehicle battery cables before connecting
the charger to the battery. Do not use
a “fast charger” to provide starting volt-
age.
Air Conditioner Maintenance
For best possible performance, your air con-
ditioner should be checked and serviced by
an authorized dealer at the start of each warm
season. This service should include cleaning
of the condenser fins and a performance test.
Drive belt tension should also be checked at
this time.
WARNING!
• Use only refrigerants and compressor
lubricants approved by the manufac-
turer for your air conditioning system.
Some unapproved refrigerants are flam-
mable and can explode, injuring you.
Other unapproved refrigerants or lubri-
cants can cause the system to fail, re-
quiring costly repairs. Refer to Warranty
Information Book, located in your own-
er’s information kit, for further warranty
information.
• The air conditioning system contains re-
frigerant under high pressure. To avoid
risk of personal injury or damage to the
system, adding refrigerant or any repair
SERVICING AND MAINTENANCE
186

WARNING!
requiring lines to be disconnected
should be done by an experienced tech-
nician.
CAUTION!
Do not use chemical flushes in your air
conditioning system as the chemicals can
damage your air conditioning components.
Such damage is not covered by the New
Vehicle Limited Warranty.
Refrigerant Recovery And Recycling R-134a
— If Equipped
R-134a Air Conditioning Refrigerant is a
hydrofluorocarbon (HFC) that is an ozone-
friendly substance. The manufacturer recom-
mends that air conditioning service be per-
formed by an authorized dealer or other
service facilities using recovery and recycling
equipment.NOTE:
Use only manufacturer approved A/C system
PAG compressor oil and refrigerants.
Refrigerant Recovery And Recycling —
R–1234yf
R–1234yf Air Conditioning Refrigerant is a
hydrofluoroolefin (HFO) that is endorsed by
the Environmental Protection Agency and is
an ozone-friendly substance with a low
global-warming potential. The manufacturer
recommends that air conditioning service be
performed by an authorized dealer using re-
covery and recycling equipment.
NOTE:
Use only manufacturer approved A/C system
PAG compressor oil, and refrigerants.
Air Conditioning Filter Replacement (A/C Air
Filter)
WARNING!
Do not remove the cabin air filter while the
vehicle is running, or while the ignition is
in the ACC or ON/RUN mode. With the
cabin air filter removed and the blower
operating, the blower can contact hands
and may propel dirt and debris into your
eyes, resulting in personal injury.
The A/C air filter is located in the fresh air
inlet behind the glove compartment. Perform
the following procedure to replace the filter:
1. Open the glove compartment and remove
all contents.
2. Push in on the sides of the glove compart-
ment and lower the door.
187

CAUTION!
The cabin air filter is identified with an
arrow to indicate airflow direction through
the filter. Failure to properly install the
filter will result in the need to replace it
more often.
8. Close A/C Air Filter access doors and se-
cure retaining tabs.
9. Rotate the glove compartment door back
into position.
Refer to the “Maintenance Plan” for the
proper maintenance intervals.
DEALER SERVICE
An authorized dealer has the qualified service
personnel, special tools, and equipment to
perform all service operations in an expert
manner. Service Manuals are available which
include detailed service information for your
vehicle. Refer to these Service Manuals be-
fore attempting any procedure yourself.NOTE:
Intentional tampering with emissions control
systems may void your warranty and could
result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or
around a motor vehicle. Only do service
work for which you have the knowledge
and the proper equipment. If you have any
doubt about your ability to perform a ser-
vice job, take your vehicle to a competent
mechanic.
Windshield Wiper Blades
Clean the rubber edges of the wiper blades
and the windshield periodically with a sponge
or soft cloth and a mild nonabrasive cleaner.
This will remove accumulations of salt or road
film.Operation of the wipers on dry glass for long
periods may cause deterioration of the wiper
blades. Always use washer fluid when using
the wipers to remove salt or dirt from a dry
windshield.
Avoid using the wiper blades to remove frost
or ice from the windshield. Keep the blade
rubber out of contact with petroleum prod-
ucts such as engine oil, gasoline, etc.
NOTE:
Life expectancy of wiper blades varies de-
pending on geographical area and frequency
of use. Poor performance of blades may be
present with chattering, marks, water lines or
wet spots. If any of these conditions are
present, clean the wiper blades or replace as
necessary.
The wiper blades and wiper arms should be
inspected periodically, not just when wiper
performance problems are experienced. This
inspection should include the following
points:
• Wear Or Uneven Edges
• Foreign Material
189

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 and Vehicle Stability
• Economy
• Tread Wear
• Ride Comfort
Safety
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 re-
sult in tire failure.
WARNING!
• Overinflated or underinflated tires can
affect vehicle handling and can fail sud-
denly, resulting in loss of vehicle control.
• Unequal tire pressures can cause steer-
ing 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.
Both under-inflation and over-inflation 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 steer-
ing response.
• Unequal tire pressure from side to side may
cause the vehicle to drift left or right.Fuel EconomyUnderinflated tires will increase tire rolling re-
sistance resulting in higher fuel consumption.
Tread Wear
Improper cold tire inflation pressures can
cause abnormal wear patterns and reduced
tread life, resulting in the need for earlier tire
replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfort-
able ride. Over-inflation produces a jarring
and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is
listed on the driver's side B-Pillar or rear edge
of the driver's side door.
At least once a month:
• Check and adjust tire pressure with a good
quality pocket-type pressure gauge. Do not
make a visual judgement when determining
proper inflation. Tires may look properly
inflated even when they are under-inflated.
193

• Inspect tires for signs of tire wear or visible
damage.
CAUTION!
After inspecting or adjusting the tire pres-
sure, always reinstall the valve stem cap.
This will prevent moisture and dirt from
entering the valve stem, which could dam-
age the valve stem.
Inflation pressures specified on the placard
are always “cold tire inflation pressure”. Cold
tire inflation pressure is defined as the tire
pressure after the vehicle has not been driven
for at least three hours, or driven less than
1 mile (1.6 km) after sitting for a minimum of
three hours. The cold tire inflation pressure
must not exceed the maximum inflation pres-
sure molded into the tire sidewall.
Check tire pressures more often if subject to
a wide range of outdoor temperatures, as tire
pressures vary with temperature changes.Tire pressures change by approximately 1 psi
(7 kPa) per 12°F (7°C) of air temperature
change. Keep this in mind when checking
tire pressure inside a garage, especially in the
Winter.
Example: If garage temperature = 68°F
(20°C) and the outside temperature = 32°F
(0°C) then the cold tire inflation pressure
should be increased by 3 psi (21 kPa), which
equals 1 psi (7 kPa) for every 12°F (7°C) for
this outside temperature condition.
Tire pressure may increase from 2 to 6 psi
(13 to 40 kPa) during operation. DO NOT
reduce this normal pressure build up or your
tire pressure will be too low.
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 anauthorized tire dealer or original equipment
vehicle dealer for recommended safe operat-
ing speeds, loading and cold tire inflation
pressures.
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).
Radial Ply Tires
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.
SERVICING AND MAINTENANCE
194