2023 JEEP WRANGLER fuel cap

168STARTING AND OPERATING
System Overview
This vehicle is equipped with a Diesel Exhaust Fluid (DEF)
injection system and a Selective Catalytic Reduction (SCR)
catalyst to meet the emission requirements.
The DEF injection system consists of the following
components:
DEF tank
 DEF pump
 DEF injector
 Electronically-heated DEF Lines
 NOx sensors
 Temperature sensors
 SCR catalyst
The DEF injection system and SCR catalyst enable the
achievement of diesel emission requirements; while
maintaining outstanding fuel economy, drivability, torque
and power ratings.
For system messages and warnings see
Úpage 108.
NOTE:
 Your vehicle is equipped with a DEF injection system.
You may occasionally hear an audible clicking noise
from under the vehicle at a stop. This is normal opera -
tion.
 The DEF pump will run for a period of time after engine
shutdown to purge the DEF system. This is normal
operation and may be audible from the rear of the
vehicle.
Diesel Exhaust Fluid Storage
Diesel Exhaust Fluid (DEF) is considered a very stable
product with a long shelf life. If DEF is kept in
temperatures between 10° and 90°F (-12° and 32°C), it
will last a minimum of one year.
DEF is subject to freezing at the lowest temperatures. For
example, DEF may freeze at temperatures at or below
12°F (-11°C). The system has been designed to operate
in this environment.
NOTE:When working with DEF, it is important to know that:
Any containers or parts that come into contact with DEF
must be DEF compatible (plastic or stainless steel).
Copper, brass, aluminum, iron or non-stainless steel
should be avoided as they are subject to corrosion by
DEF.
 If DEF is spilled, it should be wiped up completely.
Adding Diesel Exhaust Fluid
The DEF gauge (located on the instrument cluster display)
will display the level of DEF remaining in the tank
Úpage 108.
NOTE:Driving conditions (altitude, vehicle speed, load, etc.) will
affect the amount of DEF that is used in your vehicle.
DEF FILL PROCEDURE
NOTE:
For the correct DEF fluid type see Úpage 374.

1. Remove cap from DEF fill inlet (located in fuel door).

Fuel and Diesel Exhaust Fluid Fill Location

2. Insert DEF fill adapter/nozzle into DEF fill inlet.
NOTE:
 The DEF gauge may take up to five seconds to
update after adding a gallon or more of Diesel
Exhaust Fluid (DEF) to the DEF tank. If you have a
fault related to the DEF system, the gauge may not
update to the new level. See an authorized dealer
for service.
 The DEF gauge may also not immediately update
after a refill if the temperature of the DEF fluid is
below 12°F (-11°C). The DEF tank heater will
1 — Diesel Fuel Filler
2 — Diesel Exhaust Fluid Filler

23_JL_OM_EN_USC_t.book Page 168

STARTING AND OPERATING169
possibly warm up the DEF fluid and allow the
gauge to update after a period of run time. Under
very cold conditions, it is possible that the gauge
may not reflect the new fill level for several drives.
 Excessive overfilling of the DEF tank can result in
a MIL lamp/fault code and inaccurate level read -
ings.
Refilling With Nozzles
You can fill up at any DEF distributor.
Proceed as follows:
 Insert the DEF nozzle in the filler, start refilling and
stop refilling at the first shut-off (the shut-off indi -
cates that the DEF tank is full). Do not proceed
with the refilling, to prevent spillage of DEF.
 Extract the nozzle.
Refilling With Containers
Proceed as follows:
 Check the expiration date.
 Read the advice for use on the label before
pouring the content of the bottle into the DEF tank.
 If systems which cannot be screwed in (e.g. tanks)
are used for refilling, after the indication appears
on the instrument panel display
Úpage 104 fill
the DEF tank with no more than 2 gal (8 L).
 If containers which can be screwed to the filler are
used, the reservoir is full when the DEF level in the
container stops pouring out. Do not proceed
further. 3. Stop filling the DEF tank immediately when any of the
following happen: DEF stops flowing from the fill
bottle into the DEF fill inlet, DEF splashes out the fill
inlet, or a DEF pump nozzle automatically shuts off.
4. Reinstall cap onto DEF fill inlet.
VEHICLE LOADING
CERTIFICATION LABEL
As required by National Highway Traffic Safety
Administration regulations, your vehicle has a certification
label affixed to the driver's side door or pillar.
This label contains the month and year of manufacture,
Gross Vehicle Weight Rating (GVWR), Gross Axle Weight
Rating (GAWR) front and rear, and Vehicle Identification
Number (VIN). A Month-Day-Hour (MDH) number is
included on this label and indicates the Month, Day and
Hour of manufacture. The bar code that appears on the
bottom of the label is your VIN.
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and
rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
CAUTION!
 To avoid DEF spillage, and possible damage to the
DEF tank from overfilling, do not “top off” the DEF
tank after filling.
 DO NOT OVERFILL. DEF will freeze below 12ºF
(-11ºC). The DEF system is designed to work in
temperatures below the DEF freezing point, however,
if the tank is overfilled and freezes, the system could
be damaged.
 When DEF is spilled, clean the area immediately with
water and use an absorbent material to soak up the
spills on the ground.
 Do not attempt to start your engine if DEF is acciden -
tally added to the diesel fuel tank as it can result in
severe damage to your engine, including but not
limited to failure of the fuel pump and injectors.
 Never add anything other than DEF to the tank –
especially any form of hydrocarbon such as diesel
fuel, fuel system additives, gasoline, or any other
petroleum-based product. Even a very small amount
of these, less than 100 parts per million or less than
1 oz. per 78 gal (295 L) will contaminate the entire
DEF system and will require replacement. If owners
use a container, funnel or nozzle when refilling the
tank, it should either be new or one that has only
been used for adding DEF. Mopar® provides an
attachable nozzle with its DEF for this purpose.
4

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170STARTING AND OPERATING
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the driver,
all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for
increased durability do not necessarily increase the
vehicle's GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents
the actual tire size on your vehicle. Replacement tires
must be equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
Loading
The actual total weight and the weight of the front and rear
of your vehicle at the ground can best be determined by
weighing it when it is loaded and ready for operation.
The entire vehicle should first be weighed on a commercial
scale to ensure that the GVWR has not been exceeded.
The weight on the front and rear of the vehicle should then
be determined separately to be sure that the load is
properly distributed over the front and rear axle. Weighing
the vehicle may show that the GAWR of either the front or
rear axles has been exceeded but the total load is within
the specified GVWR. If so, weight must be shifted from
front to rear or rear to front as appropriate until the
specified weight limitations are met. Store the heavier
items down low and be sure that the weight is distributed
equally. Stow all loose items securely before driving.
Improper weight distributions can have an adverse effect
on the way your vehicle steers and handles and the way
the brakes operate.
TRAILER TOWING
In this section you will find safety tips and information on
limits to the type of towing you can reasonably do with your
vehicle. Before towing a trailer, carefully review this
information to tow your load as efficiently and safely as
possible.
To maintain the New Vehicle Limited Warranty coverage,
follow the requirements and recommendations in this
manual concerning vehicles used for trailer towing.
COMMON TOWING DEFINITIONS
The following trailer towing related definitions will assist
you in understanding the following information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your vehicle.
This includes driver, passengers, cargo and tongue
weight. The total load must be limited so that you do not
exceed the GVWR
Úpage 169.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the weight of all
cargo, consumables and equipment (permanent or
temporary) loaded in or on the trailer in its "loaded and
ready for operation" condition.
The recommended way to measure GTW is to put your fully
loaded trailer on a vehicle scale. The entire weight of the
trailer must be supported by the scale.
WARNING!
Do not load your vehicle any heavier than the GVWR or
the maximum front and rear GAWR. If you do, parts on
your vehicle can break, or it can change the way your
vehicle handles. This could cause you to lose control.
Overloading can shorten the life of your vehicle.

23_JL_OM_EN_USC_t.book Page 170

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

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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.

23_JL_OM_EN_USC_t.book Page 300

322SERVICING AND MAINTENANCE

1. Ensure engine is turned off.

2. Remove the fuel filter protective cover to access the
fuel filter assembly.

Fuel Filter Assembly

3. Place drain pan under the fuel filter assembly.
4. Open the water drain valve, and let any accumulated water and fuel drain.
5. Close the water drain valve.

Fuel Filter Assembly

6. Wipe clean the underside of the filter housing to prevent contamination from entering fuel system
during service.
7. Remove the fuel filter cap and filter from the housing using a socket. Rotate counterclockwise for removal.

Fuel Filter Assembly

8. Remove the used fuel filter cartridge from the cap and dispose of according to your local regulations.
9. Wipe clean the sealing surfaces of the cap and housing.
1 — Retainers
2 — Fuel Filter Protective Cover
1 — Water Drain Valve1 — Fuel Filter Cap
2 — Socket Adapter
CAUTION!
Take care when handling the new fuel filter to prevent
contamination from entering the fuel system.

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SERVICING AND MAINTENANCE323
10. Lubricate o-ring on the cap with clean engine oil.
11. Install the new fuel filter cartridge onto the cap.
12. Insert the cap and filter into the housing with
clockwise rotation, use a socket to tighten.
13. Push the ignition switch twice without your foot on the brake to place vehicle in RUN position. This will
activate the in tank fuel pump for approximately 30
seconds. Repeat this process twice to prime the fuel
system. Start the engine using the Normal Starting
procedure. After engine start, verify the fuel filter cap
does not leak.
PRIMING IF THE ENGINE HAS RUN OUT
O
F FUEL — DIESEL ENGINE

1. Add a substantial amount of fuel to the tank, approx -
imately 2 to 5 gal (8L to 19L).

2. Push ignition switch twice without your foot on brake to put vehicle in RUN position. This will activate the in
tank fuel pump for approximately 30 seconds.
Repeat this process twice to prime the fuel system.
3. Start the engine using the Normal Starting procedure
Úpage 130.
NOTE:The engine may run rough until the air is forced from all
the fuel lines.
NOTE:
 Use of biodiesel mixture in excess of 20% can nega -
tively impact the fuel filter's ability to separate water
from the fuel, resulting in high pressure fuel system
corrosion or damage.
 In addition, commercially available fuel additives are
not necessary for the proper operation of your diesel
engine.
 For extreme cold conditions, "Mopar® Premium Diesel
Fuel Treatment" is recommended to assist with cold
starting.
INTERVENTION REGENERATION
S
TRATEGY — MESSAGE PROCESS FLOW
This engine meets all required diesel engine emissions
standards. To achieve these emissions standards, your
vehicle is equipped with a state-of-the-art engine and
exhaust system. These systems are seamlessly integrated
into your vehicle and managed by the Powertrain Control
Module (PCM). The PCM manages engine combustion to
allow the exhaust system’s catalyst to trap and burn
Particulate Matter (PM) pollutants, with no input or
interaction on your part.
Additionally, your vehicle has the ability to alert you to
additional maintenance required on your vehicle or
engine.
Refer to Instrument Cluster Display for further information
Úpage 108.
DIESEL EXHAUST FLUID
Diesel Exhaust Fluid (DEF) sometimes known simply by
the name of its active component, UREA—is a key
component of Selective Catalytic Reduction (SCR)
systems, which help diesel vehicles meet stringent
emission regulations. DEF is a liquid reducing agent that
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
CAUTION!
The starter motor will engage for approximately
30 seconds at a time. Allow two minutes between
cranking intervals.
WARNING!
Do not use alcohol or gasoline as a fuel blending agent.
They can be unstable under certain conditions and be
hazardous or explosive when mixed with diesel fuel.
CAUTION!
Due to lack of lubricants in alcohol or gasoline, the use
of these fuels can cause damage to the fuel system.WARNING!
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.
8

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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.

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