2023 JEEP WRANGLER radiator cap

100GETTING TO KNOW YOUR VEHICLE
5. Reinstall the protective caps over the wiper arm hex
bolts and push gently until they snap into place.

Step Five

6. After completing the steps above:
If your vehicle is equipped with a Soft Top, reinstall
the Door Rails and raise the top.
 If your vehicle is equipped with a Hard Top, rein -
stall the Freedom Panels.
HOOD
OPENING THE HOOD
If applicable, refer to the “Hybrid Supplement” for
additional information.
Release both of the outside hood latches.

Hood Latch Locations

Raise the hood slightly, and place a hand palm-side down
in the center of the hood opening. Locate the safety latch
in the middle, and push the latch to the right to open.

Place Hand In Hood Opening

Remove the support rod from the hood, and insert it into
the radiator crossmember.

Hood Prop Rod Slot

1 — Hex Bolt Cover Installed
2 — Hex Bolt Cover Removed

23_JL_OM_EN_USC_t.book Page 100

IN CASE OF EMERGENCY299

Positive (+) Battery Post – Diesel Engine

NOTE:The positive (+) battery post is covered with a protective
cap. Lift up on the cap to gain access to the post.
If your vehicle is equipped with a Stop/Start system, it will
be equipped with two batteries
Úpage 147.
See the following steps to prepare for jump starting:

1. Apply the parking brake, shift the automatic transmission into PARK (P) (manual transmission in
NEUTRAL) and turn the ignition OFF.

2. Turn off the heater, radio, and all electrical accessories.
3. Pull upward and remove the protective cover over the positive (+) battery post.
4. If using another vehicle to jump start the battery, park the vehicle within the jumper cable’s reach, apply the
parking brake and make sure the ignition is OFF.
JUMP STARTING PROCEDURE
Connecting The Jumper Cables

1. Connect the positive
(+) end of the jumper cable to
the positive (+)
post of the discharged vehicle.

2. Connect the opposite end of the positive (+) jumper
cable to the positive (+) post of the booster battery.
3. Connect the negative (-) end of the jumper cable to
the negative (-) post of the booster battery.
4. Connect the opposite end of the negative (-) jumper
cable to a good engine ground. A “ground” is an
exposed metallic/unpainted part of the engine, frame
or chassis, such as an accessory bracket or large bolt.
The ground must be away from the battery and the
fuel injection system.

Jump Starting Label

WARNING!
 Take care to avoid the radiator cooling fan whenever
the hood is raised. It can start anytime the ignition
switch is ON. You can be injured by moving fan
blades.
 Remove any metal jewelry such as rings, watch
bands and bracelets that could make an inadvertent
electrical contact. You could be seriously injured.
 Batteries contain sulfuric acid that can burn your
skin or eyes and generate hydrogen gas which is
flammable and explosive. Keep open flames or
sparks away from the battery.
WARNING!
Do not allow vehicles to touch each other as this could
establish a ground connection and personal injury
could result.
WARNING!
Failure to follow this jump starting procedure could
result in personal injury or property damage due to
battery explosion.
WARNING!
Do not connect the jumper cable to the negative (-) post
of the discharged battery. The resulting electrical spark
could cause the battery to explode and could result in
personal injury.
7

23_JL_OM_EN_USC_t.book Page 299

300IN CASE OF EMERGENCY
5. Start the engine in the vehicle that has the booster
battery, let the engine idle a few minutes, and then
start the engine in the vehicle with the discharged
battery.
6. Once the engine is started, remove the jumper cables in the reverse sequence.
Disconnecting The Jumper Cables

1. Disconnect the negative
(-)
end of the jumper cable
from the engine ground of the vehicle with the
discharged battery.

2. Disconnect the opposite end of the negative (-)
jumper cable from the negative (-) post of the booster
battery.
3. Disconnect the positive (+) end of the jumper cable
from the positive (+) post of the booster battery. 4. Disconnect the opposite end of the positive
(+)
jumper cable from the positive (+) post of the
discharged vehicle.
5. Reinstall the protective cover over the positive (+)
post of the discharged vehicle.
NOTE:If frequent jump starting is required to start your vehicle
you should have the battery and charging system tested at
an authorized dealer.
IF YOUR ENGINE OVERHEATS
If the vehicle is overheating, it will need to be serviced by
an authorized dealer.
Potential signs of vehicle overheating:
 Temperature gauge is at HOT (H)
 Strong smell of coolant
 White smoke coming from engine or exhaust
 Coolant bottle coolant has bubbles present In the event it is observed that the temperature gauge is
moving towards or close to the HOT (H) position, you can
reduce the potential for overheating by taking the
appropriate action.

On the highways — slow down.
 In city traffic — while stopped, place the transmission in
NEUTRAL (N), but do not increase the engine idle speed
while preventing vehicle motion with the brakes.
 If your Air Conditioner (A/C) is on, turn it off. The A/C
system adds heat to the engine cooling system and
turning the A/C off can help remove this heat.
 You can also turn the temperature control to maximum
heat, the mode control to floor and the blower control
to high. This allows the heater core to act as a supple -
ment to the radiator and aids in removing heat from the
engine cooling system.
CAUTION!
Make sure at all times that unused ends of jumper
cables are not contacting each other or either vehicle
while making connections. Failure to follow these
procedures could result in damage to the charging
system of the booster vehicle or the discharged vehicle.
CAUTION!

Do not run the booster vehicle engine above 2,000 RPM
since it provides no charging benefit, wastes fuel, and
can damage booster vehicle engine.

CAUTION!
Accessories plugged into the vehicle power outlets draw
power from the vehicle’s battery, even when not in use
(i.e., cellular devices, etc.). Eventually, if plugged in long
enough without engine operation, the vehicle’s battery
will discharge sufficiently to degrade battery life and/or
prevent the engine from starting.
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 try to open a cooling system pressure cap when
the radiator or coolant bottle is hot.

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328SERVICING AND MAINTENANCE
(Continued)
(Continued)
Installing The Rear Wiper

1. Lift the wiper arm off of the glass.

2. Insert the wiper blade pivot pin into the opening on
the end of the wiper arm and rotate the wiper in to
place.
3. Place with wiper on the glass and close the tail gate.
EXHAUST SYSTEM
The best protection against carbon monoxide entry into
the vehicle body is a properly maintained engine exhaust
system.
If you notice a change in the sound of the exhaust system;
or if the exhaust fumes can be detected inside the vehicle;
or when the underside or rear of the vehicle is damaged;
have an authorized technician inspect the complete
exhaust system and adjacent body areas for broken,
damaged, deteriorated, or mispositioned parts. Open
seams or loose connections could permit exhaust fumes
to seep into the passenger compartment. In addition, have
the exhaust system inspected each time the vehicle is
raised for lubrication or oil change. Replace as required.
Under normal operating conditions, the catalytic converter
will not require maintenance. However, it is important to
keep the engine properly tuned to ensure proper catalyst
operation and prevent possible catalyst damage.
NOTE:Intentional tampering with emissions control systems can
result in civil penalties being assessed against you.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop the
vehicle, turn off the engine and allow it to cool. Service,
including a tune-up to manufacturer's specifications,
should be obtained immediately.
To minimize the possibility of catalytic converter damage:
Do not interrupt the ignition when the transmission is
in gear and the vehicle is in motion.
 Do not try to start the vehicle by pushing or towing the
vehicle.
 Do not idle the engine with any ignition components
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough idle
or malfunctioning operating conditions.
COOLING SYSTEM
WARNING!
Exhaust gases can injure or kill. They contain Carbon
Monoxide (CO), which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you
Úpage 288.
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your
exhaust system. Do not park or operate your vehicle
in areas where your exhaust system can contact
anything that can burn.
CAUTION!
The catalytic converter requires the use of unleaded
fuel only. Leaded gasoline will destroy the effective -
ness of the catalyst as an emissions control device
and may seriously reduce engine performance and
cause serious damage to the engine.
 Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly
involving engine misfire or other apparent loss of
performance, have your vehicle serviced promptly.
Continued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and
vehicle.
WARNING!
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 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 automatically and may start at any time,
whether the engine is running or not.

23_JL_OM_EN_USC_t.book Page 328

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!
8

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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.

23_JL_OM_EN_USC_t.book Page 330

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.
8

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383
Bulb Replacement .............................................. 342, 343
Bulbs, Light.......................................................... 290, 342
Bumper End Cap Removal .......................................... 178
CCamera, Rear ............................................................... 163
Capacities, Fluid ........................................................... 373
Caps, Filler Fuel .......................................................................... 165
Oil (Engine) .............................................................. 314
Radiator (Coolant Pressure)................................... 330
Car Washes .................................................................. 361
Carbon Monoxide Warning .......................................... 290
Cargo Load Floor .......................................................... 102
Cargo Tie-Downs .......................................................... 102
Carpeting ...................................................................... 363
CD.................................................................................. 210
Cellular Phone .............................................................. 240
Center High Mounted Stop Light................................. 345
Certification Label ........................................................ 169
Chains, Tire................................................................... 357
Chart, Tire Sizing .......................................................... 346
Check Engine Light (Malfunction Indicator Light) ...... 125
Checking Your Vehicle For Safety ............................... 288
Checks, Safety.............................................................. 288
Child Restraint.............................................................. 277
Child Restraints Booster Seats.......................................................... 279
Child Seat Installation ............................................ 286
How To Stow An unused ALR Seat Belt ................. 284
Infant And Child Restraints .................................... 278Locating The LATCH Anchorages ........................... 282Lower Anchors And Tethers For Children .............. 280 Older Children And Child Restraints....................... 278
Seating Positions ..................................................... 280
Clean Air Gasoline ........................................................ 369
Cleaning Wheels .....................................................................356
Climate Control Automatic ................................................................... 54
Manual ....................................................................... 57
Cold Weather Operation ............................................... 128
Compact Spare Tire ...................................................... 355
Connected Services ................ 225
, 226, 227, 228, 237
Connector UCI .............................................................................. 61
Universal Consumer Interface (UCI) ......................... 61
Console............................................................................ 60 Floor ........................................................................... 60
Contract, Service .......................................................... 379
Controls ......................................................................... 201
Cooling Pressure Cap (Radiator Cap) ..........................330
Cooling System ............................................................. 328 Adding Coolant (Antifreeze) ....................................329
Coolant Level ...........................................................330
Cooling Capacity ...................................................... 373
Disposal Of Used Coolant ....................................... 330Drain, Flush, And Refill............................................329
Inspection ...................................................... 329
, 330
Points To Remember............................................... 331
Pressure Cap ...........................................................330
Radiator Cap ............................................................330 Selection Of Coolant (Antifreeze) ........ 329
, 373, 374
Corrosion Protection ..................................................... 360
Cruise Control (Speed Control) .......................... 151
, 152
Cruise Light ......................................................... 123, 124 Customer Assistance ................................................... 377
Customer Programmable Features ............................. 184
Cybersecurity ................................................................ 184
DDaytime Running Lights ................................................. 51
Dealer Service .............................................................. 318
Defroster, Windshield .................................................. 289
Delay (Intermittent) Wipers............................................ 53
Deleting A Phone .......................................................... 216
Diagnostic System, Onboard ....................................... 124
Diesel Display Messages ................................................... 115
Diesel Fuel .................................................................... 371
Diesel Fuel Requirements ........................................... 371 Bulk Storage Of ....................................................... 167
Diesel Fuel System, Re-Priming .................................. 323
Dimmer Switch Headlight ................................................................... 51
Dipsticks Oil (Engine) .............................................................. 317
Disable Vehicle Towing ................................................ 303
Disc Drive ...................................................................... 210
Disconnecting ............................................................... 216
Disposal Antifreeze (Engine Coolant) .................................... 330
Disturb........................................................................... 219
Door Ajar .............................................................. 117
, 119
Door Ajar Light ..................................................... 117, 119
Door Frame ..................................................................... 95 Installation ................................................................. 95
Removal..................................................................... 95
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