2023 JEEP WRANGLER check engine

SERVICING AND MAINTENANCE329
Coolant Checks
Check the engine, battery (if equipped), intercooler (if
equipped), and Motor Generator Unit (MGU) (if equipped)
coolant (antifreeze) protection every 12 months (before
the onset of freezing weather, where applicable). If the
engine, battery (if equipped), intercooler (if equipped), and
MGU (if equipped) coolant 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, battery (if equipped), intercooler (if
equipped), and MGU (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.
Cooling System — Drain, Flush And Refill
NOTE:Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could lead to severe internal engine damage. If any coolant is needed
to be added to the system please contact an authorized
dealer.
If the engine coolant (antifreeze) is dirty or contains visible
sediment, have an authorized dealer clean and flush with
OAT coolant (conforming to MS.90032).
For the proper maintenance intervals, see
Úpage 307 for
gasoline engines or Úpage 311 for diesel engines.
Selection Of Coolant
For further information Úpage 374.
NOTE:
 Mixing of engine coolant (antifreeze) other than speci-
fied Organic Additive Technology (OAT) engine coolant,
may result in engine damage and may decrease corro -
sion protection. OAT engine coolant is different and
should not be mixed with Hybrid Organic Additive Tech -
nology (HOAT) engine coolant or any “globally compat -
ible” coolant. If a non-OAT engine coolant is introduced
into the cooling system in an emergency, the cooling
system will need to be drained, flushed, and refilled
with fresh OAT coolant (conforming to MS.90032), by
an authorized dealer as soon as possible.
 Do not use water alone or alcohol-based engine
coolant (antifreeze) products. Do not use additional
rust inhibitors or anti-rust products, as they may not be
compatible with the radiator engine coolant and may
plug the radiator.
 This vehicle has not been designed for use with
propylene glycol-based engine coolant. Use of
propylene glycol-based engine coolant is not recom -
mended. 
Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could
lead to severe internal engine damage. If any coolant is
needed to be added to the system please contact an
authorized dealer.
Adding Coolant

Your vehicle has been built with an improved engine coolant
(OAT coolant conforming to MS.90032) that allows
extended maintenance intervals. This engine coolant
(antifreeze) can be used up to 10 years or 150,000 miles
(240,000 km) before replacement. To prevent reducing this
extended maintenance period, it is important to use the
same engine coolant (OAT coolant conforming to
MS.90032) throughout the life of your vehicle.

Please review these recommendations for using Organic
Additive Technology (OAT) engine coolant that meets the
requirements of the manufacturer Material Standard
MS.90032. When adding engine coolant (antifreeze):
We recommend using Mopar® Antifreeze/Coolant
10 Year/150,000 Mile (240,000 km) Formula OAT
(Organic Additive Technology) that meets the require -
ments of the manufacturer Material Standard
MS.90032.
 Mix a minimum solution of 50% OAT engine coolant
that meets the requirements of the manufacturer
Material Standard MS.90032 and distilled water. Use
higher concentrations (not to exceed 70%) if tempera -
tures below −34°F (−37°C) are anticipated. Please
contact an authorized dealer for assistance.
 Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.
The use of lower quality water will reduce the amount
of corrosion protection in the engine cooling system.

When working near the radiator cooling fan, discon -
nect 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.
WARNING!
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330SERVICING AND MAINTENANCE
NOTE:
It is the owner's responsibility to maintain the proper
level of protection against freezing according to the
temperatures occurring in the area where the vehicle is
operated.
 Use care when filling under hood fluids such as engine
oil, washer fluid, antifreeze, etc., to minimize spillage
onto the top of the engine. Any excess fluid that is
spilled onto the top of the engine should be removed
using compressed air or an absorbent cloth.
 Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could
lead to severe internal engine damage. If any coolant is
needed to be added to the system, please contact an
authorized dealer.
 Mixing engine coolant types is not recommended and
can result in cooling system damage. If HOAT and OAT
coolant are mixed in an emergency, have an authorized
dealer drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that engine coolant will
return to the radiator from the coolant expansion bottle/
recovery tank if so equipped.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze) OAT or
HOAT, is a regulated substance requiring proper disposal.
Check with your local authorities to determine the disposal
rules for your community. To prevent ingestion by animals
or children, do not store ethylene glycol-based coolant in
open containers or allow it to remain in puddles on the
ground, clean up any ground spills immediately. If
ingested, seek emergency assistance immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine OFF and cold, the level of the engine coolant
(antifreeze) in the bottle should be between the ranges
indicated on the bottle. The radiator normally remains completely full, so there is
no need to remove the radiator/coolant pressure cap
unless checking for engine coolant freeze point or
replacing coolant. Advise your service attendant of this. As
long as the engine operating temperature is satisfactory,
the coolant bottle need only be checked once a month.
When additional engine coolant is needed to maintain the
proper level, only OAT coolant that meets the
requirements of the manufacturer Material Standard
MS.90032 should be added to the coolant bottle. Do not
overfill.
Engine Coolant Level — 2.0L
WARNING!

Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is over -
heated. Do not loosen or remove the cap to cool an
overheated engine. Heat causes pressure to build up
in the cooling system. To prevent scalding or injury,
do not remove the pressure cap while the system is
hot or under pressure.
 Do not use a pressure cap other than the one speci -
fied for your vehicle. Personal injury or engine
damage may result.
WARNING!
 Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is over -
heated. Do not loosen or remove the cap to cool an
overheated engine. Heat causes pressure to build up
in the cooling system. To prevent scalding or injury,
do not remove the pressure cap while the system is
hot or under pressure.
 Do not use a pressure cap other than the one speci -
fied for your vehicle. Personal injury or engine
damage may result.

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SERVICING AND MAINTENANCE331
(Continued)
With the engine OFF and cold, the level of the engine
coolant should be within the OK range between the ADD
and FULL range on the dipstick.

1. Remove the cap with level dipstick from the engine
coolant bottle.

2. Clean off the coolant from the dipstick.
3. Rest the cap on the opening of the coolant bottle without tightening the cap.
4. Remove the cap with dipstick and check the coolant level on the dipstick.
The radiator normally remains completely full, so there is
no need to remove the radiator/coolant pressure cap
unless checking for engine coolant freeze point or
replacing coolant. Advise your service attendant of this. As
long as the engine operating temperature is satisfactory,
the coolant bottle need only be checked once a month.
When additional engine coolant is needed to maintain the
proper level, only OAT coolant that meets the
requirements of the manufacturer Material Standard
MS.90032 should be added to the coolant bottle. Do not
overfill.
Cooling System Notes
NOTE:When the vehicle is stopped after a few miles/kilometers
of operation, you may observe vapor coming from the front
of the engine compartment. This is normally a result of
moisture from rain, snow, or high humidity accumulating
on the radiator and being vaporized when the thermostat
opens, allowing hot engine coolant (antifreeze) to enter
the radiator. If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.

Do not overfill the coolant expansion bottle.
 Check the coolant freeze point in the radiator and in
the coolant expansion bottle. If engine coolant needs
to be added, the contents of the coolant expansion
bottle must also be protected against freezing.
 If frequent engine coolant additions are required, the
cooling system should be pressure tested for leaks.
 Maintain engine coolant concentration at a minimum
of 50% OAT coolant (conforming to MS.90032) and
distilled water for proper corrosion protection of your
engine which contains aluminum components.
 Make sure that the coolant expansion bottle overflow
hoses are not kinked or obstructed.
 Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
 Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory engine cooling performance,
poor gas mileage, and increased emissions.BRAKE SYSTEM
In order to ensure brake system performance, all brake
system components should be inspected periodically. For
the proper maintenance intervals
Úpage 307.
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
Úpage 376.
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 the manufacturer recommended brake fluid Úpage 376. 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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332SERVICING AND MAINTENANCE
FRONT/REAR AXLE FLUID
For normal service, periodic fluid level checks are not
required. When the vehicle is serviced for other reasons
the exterior surfaces of the axle assembly should be
inspected. If gear oil leakage is suspected inspect the fluid
level.
Fluid Level Check
Lubricant should be approximately 1/8 inch (3 mm) below
the bottom edge of the oil fill hole.
NOTE:Make sure that the vehicle is level and supported by the
axles.
Adding Fluid
Add lubricant only at the fill hole and only to the level
specified above.
Selection Of Lubricant
Use only manufacturer recommended fluid Úpage 376.
TRANSFER CASE
Fluid Level Check
The fluid level should be to the bottom edge of the fill hole
when the vehicle is in a level position.

Transfer Case

Drain And Refill
For the proper maintenance intervals Úpage 307.
Selection Of Lubricant
Use only the manufacturer recommended fluid Úpage 376.
MANUAL TRANSMISSION — IF EQUIPPED
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.
Frequency Of Fluid Change
Under normal operating conditions, the fluid installed at
the factory will give satisfactory lubrication for the life of
the vehicle. If the fluid becomes contaminated with water,
it should be changed immediately. Otherwise, change the
fluid as recommended in the Maintenance Plan. Refer to
the Maintenance Plan for the proper maintenance
intervals
Úpage 307.
Selection Of Lubricant
Use only the manufacturer recommended manual
transmission fluid Úpage 376.

To avoid contamination from foreign matter or mois -
ture, use only new brake fluid or fluid that has been
in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in an 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 failure. This could
result in a collision.
 Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing the
brake fluid to 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.
WARNING!
1 — Fill hole
2 — Drain hole

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SERVICING AND MAINTENANCE333
(Continued)
AUTOMATIC TRANSMISSION —
I
F EQUIPPED
Special Additives
It is strongly recommended against using any special
additives in the transmission. Automatic Transmission
Fluid (ATF) is an engineered product and its performance
may be impaired by supplemental additives. Therefore, do
not add any fluid additives to the transmission. Avoid
using transmission sealers as they may adversely affect
seals.
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
transmission 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.
Fluid And Filter Changes
Under normal operating conditions, the fluid installed at
the factory will provide satisfactory lubrication for the life
of the vehicle.
Routine fluid and filter changes are not required. However,
change the fluid and filter if the fluid becomes
contaminated (with water, etc.), or if the transmission is
disassembled for any reason.
Selection Of Lubricant
It is important to use the proper transmission fluid to
ensure optimum transmission performance and life. Use
only the manufacturer specified transmission fluid
Úpage 376. It is important to maintain the transmission
fluid at the correct level using the recommended fluid.
NOTE:No chemical flushes should be used in any transmission;
only the approved lubricant should be used.
FUSES
General Information
CAUTION!
Do not use chemical flushes in your transmission as the
chemicals can damage your transmission components.
Such damage is not covered by the New Vehicle Limited
Warranty.
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.
CAUTION!
Using a transmission fluid other than the manufacturer
recommended fluid may cause deterioration in
transmission shift quality and/or torque converter
shudder
Úpage 376.
WARNING!
 When replacing a blown fuse, always use an appro -
priate replacement fuse with the same amp rating as
the original fuse. Never replace a fuse with another
fuse of higher amp rating. The use of a fuse with a
rating other than indicated may result in a dangerous
electrical system overload. If a properly rated fuse
continues to blow, it indicates a problem in the circuit
that must be corrected. Never replace a blown fuse
with metal wires or any other material. 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 disengaged.
 If the replaced fuse blows again, contact an autho -
rized dealer.
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334SERVICING AND MAINTENANCE
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 using power outlets for
extended periods of time with the engine off may result in
vehicle battery discharge.

Blade Fuses

Power Distribution Center (PDC)
The Power Distribution Center is located in the engine
compartment near the battery. This center contains
cartridge fuses, mini fuses, and relays. The PDC top cover
is labeled with each serviceable fuse/relay location,
function, and size.

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.WARNING!
1 — Fuse Element
2 — Blade Fuse with a good/functional fuse element
3 — Blade fuse with a bad/not functional fuse element
(blown fuse)
CAUTION!
When installing the power distribution center cover, it is
important to ensure the cover is properly positioned
and fully latched. Failure to do so may allow water to get
into the power distribution center and possibly result in
an electrical system failure.

23_JL_OM_EN_USC_t.book Page 334

TECHNICAL SPECIFICATIONS369

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.
FUEL REQUIREMENTS — GASOLINE ENGINE
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 a dealer
immediately. Use of gasoline with an octane number lower
than recommended can cause engine failure and may
void the New Vehicle Limited Warranty. Poor quality gasoline can cause problems such as hard
starting, stalling, and hesitations. If you experience these
symptoms, try another brand of gasoline before
considering service for the vehicle.
2.0L ENGINE
This engine is designed to meet all emissions
requirements, and provide satisfactory fuel
economy and performance, when using
high-quality unleaded regular gasoline having
an octane rating of 87, as specified by the (R+M)/
2 method. The use of 91 or higher octane premium
gasoline will allow these engines to operate to optimal
performance. This increase in performance is most
noticeable in hot weather or under heavy load conditions
such as while towing.
3.6L ENGINE
This engine is designed to meet all emissions
regulations and provide satisfactory fuel
economy and performance when using
high-quality unleaded regular gasoline having
an octane rating of 87 as specified by the (R+M)/
2 method. The use of higher octane premium gasoline will
not provide any benefit over regular gasoline in these
engines.
REFORMULATED GASOLINE
Many areas of the country require the use of cleaner
burning gasoline referred to as “reformulated gasoline”.
Reformulated gasoline contains oxygenates and are
specifically blended to reduce vehicle emissions and
improve air quality. The use of reformulated gasoline is recommended.
Properly blended reformulated gasoline will provide
improved performance and durability of engine and fuel
system components.
MATERIALS ADDED TO FUEL
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 will help improve fuel economy,
reduce emissions, and maintain vehicle performance.
Designated TOP TIER Detergent Gasoline
contains a higher level of detergents to further
aide in minimizing engine and fuel system
deposits. When available, the usage of TOP
TIER Detergent gasoline is recommended. Visit
www.toptiergas.com for a list of TOP TIER Detergent
Gasoline retailers.
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.
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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382
INDEX
AAbout Your Brakes ....................................................... 368
Adaptive Cruise Control (ACC)
(Cruise Control) ................................................... 151
, 152
Adding Engine Coolant (Antifreeze) ............................ 329
Adding Fuel.......................................................... 165
, 166
Additives, Fuel .............................................................. 369
Advance Phone Connectivity ....................................... 220
Air Bag Air Bag Operation.................................................... 269
Air Bag Warning Light .................................... 267
, 269
Enhanced Accident Response ...................... 276, 305
Event Data Recorder (EDR).................................... 305 Front Air Bag .................................................. 268
, 269
If Deployment Occurs ............................................. 275
Knee Impact Bolsters ............................................. 274
Maintaining Your Air Bag System .......................... 277
Maintenance ........................................................... 277
Redundant Air Bag Warning Light ......................... 267
Transporting Pets.................................................... 288
Air Bag Light ...............................................117
, 267, 289
Air Cleaner, Engine (Engine Air Cleaner Filter) ........... 319
Air Conditioner Maintenance ...................................... 324
Air Conditioner Refrigerant ................................. 324
, 325
Air Conditioner System ................................................ 324
Air Conditioning Filter ........................................... 59
, 325
Air Conditioning System..................................................59 Air Conditioning, Operating Tips ..................................... 59Air Filter......................................................................... 319
Air Pressure Tires ......................................................................... 352 Alarm
Arm The System......................................................... 20
Disarm The System ................................................... 20
Security Alarm...................................................19
, 119
Alterations/Modifications Vehicle.......................................................................... 8
Android Auto........................................................ 222
, 223
Android Auto™
S
....................................................... 222
Antifreeze (Engine Coolant) ............................... 329, 373
Disposal ...................................................................330
Anti-Lock Brake System (ABS) ..................................... 244
Anti-Lock Warning Light................................................ 119
Apple CarPlay ...................................................... 222
, 225
Apple CarPlay®
S
...................................................... 224
Assist, Hill Start ............................................................. 249
Audio Settings ............................................................... 208
Audio Systems (Radio) ................................................. 184
Auto Down Power Windows............................................ 66
Automatic Dimming Mirror ............................................. 45 Automatic Door Locks .................................................... 23Automatic Headlights ..................................................... 51Automatic High Beams ................................................... 51
Automatic Temperature Control (ATC) .......................... 59
Automatic Transmission ............................................... 138 Adding Fluid ............................................................. 333
Fluid And Filter Change ...........................................333
Fluid Change ............................................................333Fluid Level Check ....................................................333Fluid Type ....................................................... 333
, 376
Gear Ranges ............................................................138 Special Additives ..................................................... 333 Automatic Transmission Limp Home Mode ............... 139
AutoPark ....................................................................... 127
Auxiliary Electrical Outlet (Power Outlet) ...................... 62
Auxiliary Power Outlet .................................................... 62
Auxiliary Switches ........................................................... 64
Axle Fluid....................................................................... 376
Axle Lock ....................................................................... 144
BBattery..................................................................117, 317
Charging System Light ............................................ 117
Keyless Key Fob Replacement................................. 14
Belts, Seat..................................................................... 288
Blind Spot Monitoring .................................................. 252
Bluetooth Connecting To A Particular Mobile Phone OrAudio Device After Pairing ................................. 216
Body Mechanism Lubrication ...................................... 326
B-Pillar Location ........................................................... 349
Brake Assist System..................................................... 245
Brake Control System .................................................. 245
Brake Fluid...........................................................331
, 376
Brake System ......................................................331, 368
Anti-Lock (ABS) ........................................................ 368 Fluid Check .............................................................. 331Master Cylinder ....................................................... 331Parking..................................................................... 133Warning Light .......................................................... 117
Brake/Transmission Interlock ..................................... 138

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