catalytic converter JEEP WRANGLER 2023 Owners Manual

116GETTING TO KNOW YOUR INSTRUMENT PANEL
Your vehicle has the ability to alert you to additional
maintenance required on your vehicle or engine. Refer to
the following messages that may be displayed on your
instrument cluster display:
Exhaust Filter Nearing Full Safely Drive at Consistent
Speeds to Clear — This message will be displayed if the
exhaust particulate filter reaches 80% of its maximum
storage capacity. Under conditions of exclusive short
duration and low speed driving cycles, your diesel
engine and exhaust after-treatment system may never
reach the conditions required to cleanse the filter to
remove the trapped PM. If this occurs, the “Exhaust Filter XX% Full Safely Drive at Highway Speeds to
Remedy” message will be displayed. If this message is
displayed, you will hear one chime to assist in alerting
you of this condition. By simply driving your vehicle at
highway speeds for up to 20 minutes, you can remedy
the condition in the particulate filter system and allow
your diesel engine and exhaust after-treatment system
to cleanse the filter to remove the trapped PM and
restore the system to normal operating condition.
 Exhaust System Regeneration in Process Continue
Driving — This message indicates that the DPF is
self-cleaning. Maintain your current driving condition
until regeneration is completed.
 Exhaust System — Regeneration Completed — This
message indicates that the DPF self-cleaning is
completed. If this message is displayed, you will hear
one chime to assist in alerting you of this condition.
 Exhaust System Service Required — See Dealer — This
messages indicates regeneration has been disabled
due to a system malfunction. At this point the engine
Powertrain Control Module (PCM) will register a fault
code, the instrument panel will display a Malfunction
Indicator Light (MIL).
 Exhaust Filter Full — Power Reduced See Dealer — This
message indicates the PCM has derated the engine to
limit the likelihood of permanent damage to the
after-treatment system. If this condition is not
corrected and a dealer service is not performed, exten -sive exhaust after-treatment damage can occur. To
correct this condition it will be necessary to have your
vehicle serviced by an authorized dealer.
NOTE:Failing to follow the oil change indicator, changing your oil
and resetting the oil change indicator by 0 miles (0 kilo
-
meters) remaining will prevent the diesel exhaust filter
from performing its cleaning routine. This will shortly result
in a Malfunction Indicator Light (MIL) and reduced engine
power. Only an authorized dealer will be able to correct
this condition.
FUEL SYSTEM MESSAGES
The following chart contains a list of different messages
that may appear in the instrument cluster, depending on
different system or fuel conditions. Use the descriptions to
interpret what the message means and determine the
best action to take.
WARNING LIGHTS AND MESSAGES
The warning/indicator lights will illuminate in the
instrument panel together with a dedicated message and/
or acoustic signal when applicable. These indications are
indicative and precautionary and as such must not be
considered as exhaustive and/or alternative to the
information contained in the Owner’s Manual, which you
are advised to read carefully in all cases. Always refer to
WARNING!
A malfunctioning catalytic converter, as previously
referenced, can reach higher temperatures than in
normal operating conditions. This can cause a fire if you
drive slowly or park over flammable substances such as
dry plants, wood, cardboard, etc. This could result in
death or serious injury to the driver, occupants or
others.
CAUTION!
The engine may be switched off even if the warning
light is on: repeated interruptions of the regeneration
process could cause an early deterioration of engine oil.
For this reason it is always advisable to wait for the
symbol to go off before turning off the engine, following
the previously mentioned instructions. Do not complete
the DPF regeneration process when the vehicle is
stopped.
CAUTION!
See an authorized dealer, as damage to the exhaust
system could occur soon with continued operation.
CAUTION!
See an authorized dealer, as damage to the exhaust
system could occur soon with continued operation.

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120GETTING TO KNOW YOUR INSTRUMENT PANEL
Electronic Stability Control (ESC) OFF
Warning Light — If Equipped
This warning light indicates the ESC is off.
Each time the ignition is turned to ON/RUN or
ACC/ON/RUN, the ESC system will be on, even
if it was turned off previously.
Loose Fuel Filler Cap Warning Light —
If Equipped
This warning light will illuminate when the fuel
filler cap is loose. Properly close the filler cap to
disengage the light. If the light does not turn
off, please see an authorized dealer.
Low Fuel Warning Light
When the fuel level reaches approximately 2.0
gal (7.5 L), this light will turn on and a chime will
sound. The light will remain on until fuel is
added.
Low Washer Fluid Warning Light —
If Equipped
This warning light will illuminate when the
windshield washer fluid is low Úpage 314.
Engine Check/Malfunction Indicator
Warning Light (MIL)
The MIL is a part of an Onboard Diagnostic
System called OBD II that monitors engine and
automatic transmission control systems. This
warning light will illuminate when the ignition is in the ON/RUN position before engine start. If the bulb
does not come on when turning the ignition switch from
OFF to ON/RUN, have the condition checked promptly.
Certain conditions, such as a loose or missing gas cap,
poor quality fuel, etc., may illuminate the light after engine
start. The vehicle should be serviced if the light stays on
through several typical driving styles. In most situations,
the vehicle will drive normally and will not require towing.
When the engine is running, the MIL may flash to alert
serious conditions that could lead to immediate loss of
power or severe catalytic converter damage. The vehicle
should be serviced by an authorized dealer as soon as
possible if this occurs.
AdBlue® (UREA) Injection System Failure
Warning Light — If Equipped
This warning light will illuminate along with a
dedicated message on the display (if equipped)
if an unknown fluid not conforming with
acceptable characteristics is inserted, or if an
average consumption of AdBlue® (UREA) over 50% is
detected. Contact an authorized dealer as soon as
possible.
If the problem is not solved, a specific message will appear
on the instrument cluster display whenever a certain
threshold is reached until it will no longer be possible to
start the engine.
When about 125 miles (200 km) are remaining before the
AdBlue® (UREA) tank is empty, a continuous dedicated
message will appear on the instrument panel,
accompanied by a chime.
Service 4WD Warning Light — If Equipped
This warning light will illuminate to signal a fault
with the 4WD system. If the light stays on or
comes on during driving, it means that the 4WD
system is not functioning properly and that
service is required. We recommend you drive to the
nearest service center and have the vehicle serviced
immediately.
Service Adaptive Cruise Control Warning
Light — If Equipped
This light will turn on when a ACC is not
operating and needs service Úpage 152.
WARNING!
A malfunctioning catalytic converter, as previously
referenced, can reach higher temperatures than in
normal operating conditions. This can cause a fire if you
drive slowly or park over flammable substances such as
dry plants, wood, cardboard, etc. This could result in
death or serious injury to the driver, occupants or
others.
CAUTION!
Prolonged driving with the Malfunction Indicator Light
(MIL) on could cause damage to the vehicle control
system. It also could affect fuel economy and
driveability. If the MIL is flashing, severe catalytic
converter damage and power loss will soon occur.
Immediate service is required.

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124GETTING TO KNOW YOUR INSTRUMENT PANEL
Selec-Speed Control Indicator Light —
If Equipped
This light will turn on when “Selec-Speed
Control” is activated.
To activate “Selec-Speed Control”, ensure the vehicle is in
4WD Low and push the button on the Instrument Panel.
NOTE:If the vehicle is not in 4WD Low, “To Enter Selec-Speed
Shift to 4WD Low” will appear in the instrument cluster
display.
Cruise Control Ready Indicator Light —
If Equipped With A Premium Instrument
Cluster
This light will turn on when the Cruise Control
has been turned on, but not set.
Cruise Control SET Indicator Light —
If Equipped With Base Instrument Cluster
This indicator light will illuminate when the
Cruise Control is set.
BLUE INDICATOR LIGHTS
High Beam Indicator Light
This indicator light will illuminate to indicate
that the high beam headlights are on. With the
low beams activated, push the multifunction
lever forward (toward the front of the vehicle) to
turn on the high beams. Pull the multifunction lever
rearward (toward the rear of the vehicle) to turn off the
high beams. If the high beams are off, pull the lever toward
you for a temporary high beam on, "flash to pass"
scenario.
GRAY INDICATOR LIGHTS
Cruise Control Ready Indicator Light — If
Equipped With Base Instrument Cluster
This light will turn on when the Cruise Control
has been turned on, but not set.
ONBOARD DIAGNOSTIC SYSTEM — OBD II
Your vehicle is equipped with a sophisticated Onboard
Diagnostic system called OBD II. This system monitors the
performance of the emissions, engine, and transmission
control systems. When these systems are operating
properly, your vehicle will provide excellent performance
and fuel economy, as well as engine emissions well within
current government regulations.
If any of these systems require service, the OBD II system
will turn on the Malfunction Indicator Light (MIL). It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Although
your vehicle will usually be drivable and not need towing,
see an authorized dealer for service as soon as possible.
CAUTION!
 Prolonged driving with the MIL on could cause further
damage to the emission control system. It could also
affect fuel economy and driveability. The vehicle
must be serviced before any emissions tests can be
performed.
 If the MIL is flashing while the vehicle is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.

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128STARTING AND OPERATING
4L
AutoPark will be disabled when operating the vehicle in
4L.
The message “AutoPark Disabled ” will be displayed in the
instrument cluster.
Additional customer warnings will be given when both of
these conditions are met:
 Vehicle is not in PARK
 Driver’s door is ajar
The message “ AutoPark Not Engaged ” will be displayed in
the instrument cluster. A warning chime will continue until
you shift the vehicle into PARK or the driver’s door is
closed.
ALWAYS DO A VISUAL CHECK
that your vehicle is in PARK
by looking for the "P" in the instrument cluster display and
on the gear selector. As an added precaution, always apply
the parking brake when exiting the vehicle.
EXTENDED PARK STARTING
NOTE:Extended Park condition occurs when the vehicle has not
been started or driven for at least 30 days.
1. Install a battery charger or jumper cables to the
battery to ensure a full battery charge during the
crank cycle.

2. Place the ignition in the START position and release it when the engine starts. For vehicles equipped with
the ENGINE START/STOP button, press and hold the
brake pedal while pushing the ENGINE START/STOP
button once.
3. If the engine fails to start within 10 seconds, place the ignition in the OFF position, wait 10 to 15 seconds
to allow the starter to cool, then repeat the “Extended
Park Starting” procedure.
4. If the engine fails to start after eight attempts, allow the starter to cool for at least 10 minutes, then repeat
the procedure.
IF ENGINE FAILS TO START
If the engine fails to start after following the “Normal
Starting” procedure and the vehicle has not experience an
extended park condition, as previously defined, it may be
flooded. Push the accelerator pedal all the way to the floor
and hold it there. Crank the engine for no more than 10 to
15 seconds. This should clear any excess fuel in case the
engine is flooded. Leave the ignition in the RUN position,
release the accelerator pedal and repeat the “Normal
Starting” procedure.
EXTREME COLD WEATHER
(B
ELOW –22°F OR −30°C)
To ensure reliable starting at these temperatures, use of
an externally powered electric engine block heater
(available from an authorized dealer) is recommended.
WARNING!
If vehicle speed is above 1.2 mph (1.9 km/h), the
transmission will default to NEUTRAL until the vehicle
speed drops below 1.2 mph (1.9 km/h). A vehicle left in
the NEUTRAL position can roll. As an added precaution,
always apply the parking brake when exiting the vehicle.
CAUTION!
To prevent damage to the starter, do not crank
continuously for more than 10 seconds at a time. Wait
10 to 15 seconds before trying again.
WARNING!
 Never pour fuel or other flammable liquid into the
throttle body air inlet opening in an attempt to start
the vehicle. This could result in flash fire causing
serious personal injury.
 Do not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic trans -
mission cannot be started this way. Unburned fuel
could enter the catalytic converter and once the
engine has started, ignite and damage the converter
and vehicle.
 If the vehicle has a discharged battery, booster
cables may be used to obtain a start from a booster
battery or the battery in another vehicle. This type of
start can be dangerous if done improperly
Úpage 298.
CAUTION!
To prevent damage to the starter, do not continuously
crank the engine for more than 10 to 15 seconds at a
time. Wait 10 to 15 seconds before trying again.

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STARTING AND OPERATING179
(Continued)
The Basics Of Off-Road Driving
You will encounter many types of terrain driving off-road.
You should be familiar with the terrain and area before
proceeding. There are many types of surface conditions:
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
and ice. Every surface has a different effect on your
vehicle's steering, handling and traction. Controlling your
vehicle is one of the keys to successful off-road driving, so
always keep a firm grip on the steering wheel and
maintain a good driving posture. Avoid sudden
accelerations, turns or braking. In most cases, there are
no road signs, posted speed limits or signal lights.
Therefore, you will need to use your own good judgment on
what is safe and what is not. When on a trail, you should
always be looking ahead for surface obstacles and
changes in terrain. The key is to plan your future driving
route while remembering what you are currently driving
over.
NOTE:It is recommended that the Stop/Start system and the
Forward Collision Warning (FCW) system (if equipped) be
disabled during off-road use.
When To Use 4L Range
When off-road driving, shift into 4L for additional traction
and control on slippery or difficult terrain, ascending or
descending steep hills, and to increase low speed pulling
power. This range should be limited to extreme situations
such as deep snow, mud, steep inclines, or sand where
additional low speed pulling power is needed. Vehicle
speeds in excess of 25 mph (40 km/h) should be avoided
when in 4L.
Simultaneous Brake And Throttle
Operation
Many off-road driving conditions require the simultaneous
use of the brake and throttle (two-footed driving). When
climbing rocks, logs, or other stepped objects, using light
brake pressure with light throttle will keep the vehicle from
jerking or lurching. This technique is also used when you
need to stop and restart a vehicle on a steep incline.
Driving In Snow, Mud And Sand
SNOW
In heavy snow or for additional control and traction at
slower speeds, shift the transmission into a low gear and
the transfer case into 4L if necessary. Do not shift to a
lower gear than necessary to maintain headway.
Over-revving the engine can spin the wheels and traction
will be lost. If you start to slow to a stop, try turning your
steering wheel no more than a 1/4 turn quickly back and
forth, while still applying throttle. This will allow the tires to
get fresh traction and help maintain your momentum.
MUD
Deep mud creates a great deal of suction around the tires
and is very difficult to get through. You should use DRIVE,
with the transfer case in the 4L position to maintain your
momentum. If you start to slow to a stop, try turning your
steering wheel no more than a 1/4 turn quickly back and
forth for additional traction. Mud holes pose an increased
threat of vehicle damage and getting stuck. They are
normally full of debris from previous vehicles getting
stuck. As a good practice before entering any mud hole,
get out and determine how deep it is, if there are any
hidden obstacles and if the vehicle can be safely
recovered if stuck.
WARNING!
 Always wear your seat belt and firmly tie down cargo.
Unsecured cargo can become projectiles in an
off-road situation.
A malfunctioning catalytic converter can reach higher
temperatures than in normal operating conditions.
This can cause a fire if you drive slowly or park over
flammable substances such as dry plants, wood,
cardboard, etc. This could result in death or serious
injury to the driver, occupants or others.
CAUTION!
Do not use 4L when operating the vehicle on dry
pavement. Driveline hardware damage can result.
WARNING!
CAUTION!
On icy or slippery roads, do not downshift at high engine
RPM or vehicle speeds, because engine braking may
cause skidding and loss of control.
4

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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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370TECHNICAL SPECIFICATIONS
GASOLINE/OXYGENATE BLENDS
Some fuel suppliers blend unleaded gasoline with
oxygenates such as ethanol.
Problems that result from using gasoline containing more
than 15% ethanol (E-15) or gasoline containing methanol
are not the responsibility of the manufacturer and may
void or not be covered under New Vehicle Limited
Warranty.
DO NOT USE E-85 IN NON-FLEX FUEL
V
EHICLES
Non-Flex Fuel Vehicles (FFV) are compatible with gasoline
containing up to 15% ethanol (E-15). Use of gasoline with
higher ethanol content may void the New Vehicle Limited
Warranty.
If a Non-FFV vehicle is inadvertently fueled with E-85 fuel,
the engine will have some or all of these symptoms:
 Operate in a lean mode
 OBD II Malfunction Indicator Light on 
Poor engine performance
 Poor cold start and cold drivability
 Increased risk for fuel system component corrosion
CNG AND LP FUEL SYSTEM
M
ODIFICATIONS
Modifications that allow the engine to run on Compressed
Natural Gas (CNG) or Liquid Propane (LP) may result in
damage to the engine, emissions, and fuel system
components. Problems that result from running CNG or LP
are not the responsibility of the manufacturer and may
void or not be covered under the New Vehicle Limited
Warranty.
MMT IN GASOLINE
Methylcyclopentadienyl Manganese Tricarbonyl (MMT) is
a manganese-containing metallic additive that is blended
into some gasolines to increase octane. Gasoline blended
with MMT provides no performance advantage beyond
gasoline of the same octane number without MMT.
Gasoline blended with MMT reduces spark plug life and
reduces emissions system performance in some vehicles.
The manufacturer recommends that gasoline without
MMT be used in your vehicle. The MMT content of gasoline
may not be indicated on the gasoline pump; therefore, you
should ask your gasoline retailer whether the gasoline
contains MMT. MMT is prohibited in Federal and California
reformulated gasoline.
FUEL SYSTEM CAUTIONS
NOTE:Intentional tampering with the emissions control system
can result in civil penalties being assessed against you.
CAUTION!
DO NOT use E-85, gasoline containing methanol, or
gasoline containing more than 15% ethanol (E-15). Use
of these blends may result in starting and drivability
problems, damage critical fuel system components,
cause emissions to exceed the applicable standard,
and/or cause the Malfunction Indicator Light to
illuminate. Please observe pump labels as they should
clearly communicate if a fuel contains greater than
15% ethanol (E-15).
CAUTION!
Follow these guidelines to maintain your vehicle’s
performance:
 The use of leaded gasoline is prohibited by Federal
law. Using leaded gasoline can impair engine perfor -
mance and damage the emissions control system.
 An out-of-tune engine or certain fuel or ignition
malfunctions can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact an authorized dealer for service assistance.
 The use of fuel additives, which are now being sold
as octane enhancers, is not recommended. Most of
these products contain high concentrations of meth -
anol. Fuel system damage or vehicle performance
problems resulting from the use of such fuels or addi -
tives is not the responsibility of the manufacturer
and may void or not be covered under the New
Vehicle Limited Warranty.

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