2021 JEEP WRANGLER UNLIMITED engine

GETTING TO KNOW YOUR INSTRUMENT PANEL
64
Engine Will Not Start Service
AdBlue® System See DealerNOTE:
The display may take up to five seconds to update after adding two gallons (7.5 Liters) or more of
AdBlue® to the AdBlue® tank. If you have a fault related to the AdBlue® system, the display may not
update to the new level. See an authorized dealer for service.
AdBlue® freezes at temperatures lower than 12°F (-11°C). If the car stands for a long time at this
temperature, refilling could be difficult. For this reason, it is advised to park the vehicle in a garage
and/or heated environment, and wait for the AdBlue® to return to liquid state before topping up.
Gasoline Particulate Filter (GPF) System Messages — If Equipped:
Exhaust System Service Required The engine control unit has detected an issue with the gasoline particulate filter system. See an
authorized dealer.
Exhaust System Regeneration in
Process Continue Driving The regeneration procedure is controlled automatically by the engine control unit according to the filter
conditions and car use conditions. The following may occur during regeneration: increased levels of
noise vibration and harshness (NVH) and reduced engine performance. The driver should continue
driving normally. This message will continue to appear until regeneration is complete.
Exhaust System Regeneration
Complete The exhaust gas filter regeneration has been completed. This message will briefly appear.
Diesel Emissions Additive AdBlue® Warning Messages:
MESSAGE DESCRIPTION
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GETTING TO KNOW YOUR INSTRUMENT PANEL
66

Vehicles equipped with the Anti-Lock Brake
System (ABS) are also equipped with Electronic
Brake Force Distribution (EBD). In the event of an
EBD failure, the Brake Warning Light will turn on
along with the ABS Light. Immediate repair to the
ABS system is required.

Operation of the Brake Warning Light can be
checked by turning the ignition switch from
the OFF position to the ON/RUN position.
The light should illuminate for approximately
four seconds. The light should then turn off
unless the parking brake is applied or a brake
fault is detected. If the light does not illumi-
nate, have the light inspected by an autho -
rized dealer.
The light also will turn on when the parking
brake is applied with the ignition switch in
the ON/RUN position.
NOTE:
This light shows only that the parking brake
is applied. It does not show the degree of
brake application.
— Battery Charge Warning Light

This warning light will illuminate when the battery
is not charging properly. If it stays on while the
engine is running, there may be a malfunction with the charging system. Contact an authorized
dealer as soon as possible.

This indicates a possible problem with the
electrical system or a related component.
— Door Open Warning Light
This indicator will illuminate when a door is
ajar/open or not fully closed.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Electric Power Steering Fault Warning
Light
This warning light will turn on when there's a
fault with the Electric Power Steering (EPS)
system. Refer to “Electric Power Steering” in
“Starting And Operating” in the Owner’s
Manual for further information.
— Electronic Throttle Control (ETC)
Warning Light
This warning light will illuminate to indicate
a problem with the Electronic Throttle
Control (ETC) system. If a problem is
detected while the vehicle is running, the
light will either stay on or flash depending on
the nature of the problem. Cycle the ignition
when the vehicle is safely and completely
stopped and the transmission is placed in
the PARK (P) position. The light should turn
off. If the light remains on with the vehicle
running, your vehicle will usually be drive -
able; however, see an authorized dealer for
service as soon as possible.
NOTE:
This light may turn on if the accelerator and
brake pedals are pressed at the same time.

If the light continues to flash when the vehicle is
running, immediate service is required and you
may experience reduced performance, an
elevated/rough idle, or engine stall and your
vehicle may require towing. The light will come on
when the ignition is placed in the ON/RUN or
ACC/ON/RUN position and remain on briefly as a
bulb check. If the light does not come on during
starting, have the system checked by an
authorized dealer.

WARNING!
Continued operation with reduced assist
could pose a safety risk to yourself and
others. Service should be obtained as soon
as possible.
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67
— Engine Coolant Temperature Warning
Light
This warning light warns of an overheated
engine condition. If the engine coolant
temperature is too high, this indicator will
illuminate and a single chime will sound. If
the temperature reaches the upper limit, a
continuous chime will sound for four
minutes or until the engine is able to cool;
whichever comes first.
If the light turns on while driving, safely pull
over and stop the vehicle. If the A/C system
is on, turn it off. Also, shift the transmission
into Park and allow the vehicle to sit idle
(propulsion system active). If the tempera -
ture reading does not return to normal, turn
the engine off immediately and call for
service.
Refer to “If Your Engine Overheats” in “In
Case Of Emergency” for further information.
— Hood Open Warning Light
This indicator will illuminate when the hood
is ajar/open or not fully closed.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Oil Pressure Warning Light
This warning light will illuminate to indicate
low engine oil pressure. If the light turns on
while driving, stop the vehicle, shut off the
engine as soon as possible, and contact an
authorized dealer. A chime will sound when
this light turns on.
Do not operate the vehicle until the cause is
corrected. This light does not indicate how
much oil is in the engine. The engine oil level
must be checked under the hood.
— Oil Temperature Warning Light
This warning light will illuminate to indicate
the engine oil temperature is high. If the
light turns on while driving, stop the vehicle
and shut off the engine as soon as possible.
Wait for oil temperature to return to normal
levels.
— Seat Belt Reminder Warning Light
This warning light indicates when the driver
or passenger seat belt is unbuckled. When
the ignition is first placed in the ON/RUN or
ACC/ON/RUN position and if the driver’s
seat belt is unbuckled, a chime will sound
and the light will turn on. When driving, if the driver or front passenger seat belt
remains unbuckled, the Seat Belt Reminder
Light will flash or remain on continuously
and a chime will sound.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
— Rear Seat Belt Reminder Warning Light
— If Equipped
This light indicates when a rear seat belt is
unbuckled in the second row. When the igni -
tion is first placed in the ON/RUN or ACC/
ON/RUN position, and if a seat belt in the
second row is unbuckled, a light corre -
sponding to the specific seat will turn on in
the upper right portion of the instrument
cluster display, momentarily replacing the
configurable corner information. If a second
row seat belt that was buckled at the start of
the trip is unbuckled, the Rear Seat Belt
Reminder Light will change from green to red
and a single chime will sound.
Refer to “Occupant Restraint Systems” in
“Safety” for further information.
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GETTING TO KNOW YOUR INSTRUMENT PANEL
68
— Swing Gate Open Warning Light
This warning light will illuminate when the
swing gate is open.
NOTE:
If the vehicle is moving, there will also be a
single chime.
— Transmission Temperature Warning
Light — If Equipped
This warning light will illuminate to warn of
a high transmission fluid temperature. This
may occur with strenuous usage such as
trailer towing. If this light turns on, stop the
vehicle and shift the transmission into Park
and allow the vehicle to sit idle (propulsion
system active), until the light turns off. Once
the light turns off, you may continue to drive
normally.
— Vehicle Security Warning Light — If
Equipped
This light will flash at a fast rate for approxi -
mately 15 seconds when the vehicle security
alarm is arming, and then will flash slowly
until the vehicle is disarmed.
Yellow Warning Lights
— Anti-Lock Brake (ABS) Warning Light
This warning light monitors the Anti-Lock
Brake System (ABS). The light will turn on
when the ignition is placed in the ON/RUN or
ACC/ON/RUN position and may stay on for as
long as four seconds.
If the ABS light remains on or turns on while
driving, then the Anti-Lock portion of the
brake system is not functioning and service
is required as soon as possible. However, the conventional brake system will continue to
operate normally, assuming the Brake
Warning Light is not also on.
If the ABS light does not turn on when the
ignition is placed in the ON/RUN or ACC/ON/
RUN position, have the brake system
inspected by an authorized dealer.
— Electronic Stability Control (ESC)
Active Warning Light — If Equipped
This warning light will indicate when the
Electronic Stability Control system is Active.
The “ESC Indicator Light” in the instrument
cluster will come on when the ignition is
placed in the ON/RUN or ACC/ON/RUN posi -
tion, and when ESC is activated. It should go
out with the engine running. If the “ESC
Indicator Light” comes on continuously with
the engine running, a malfunction has been
detected in the ESC system. If this warning
light remains on after several ignition cycles,
and the vehicle has been driven several miles
(kilometers) at speeds greater than 30 mph
(48 km/h), see an authorized dealer as soon
as possible to have the problem diagnosed
and corrected.
WARNING!
If you continue operating the vehicle when
the Transmission Temperature Warning
Light is illuminated you could cause the
fluid to boil over, come in contact with hot
engine or exhaust components and cause a
fire.
CAUTION!
Continuous driving with the Transmission
Temperature Warning Light illuminated
will eventually cause severe transmission
damage or transmission failure.
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69
The “ESC OFF Indicator Light” and the
“ESC Indicator Light” come on momen-
tarily each time the ignition is placed in
the ON/RUN or ACC/ON/RUN position.
The ESC system will make buzzing or
clicking sounds when it is active. This is
normal; the sounds will stop when ESC
becomes inactive.
This light will come on when the vehicle is
in an ESC event.
— Electronic Stability Control (ESC) OFF
Warning Light — If Equipped
This warning light indicates the Electronic
Stability Control (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.
— Engine Check/Malfunction Indicator
Warning Light (MIL)
The Engine Check/Malfunction Indicator
Light (MIL) is a part of an Onboard Diag -
nostic 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. WARNING!
A malfunctioning catalytic converter, as
referenced above, 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.
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70
— AdBlue® 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® 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® tank is
empty, a continuous dedicated message will
appear on the instrument panel, accompa
-
nied by a buzzer sound (If Equipped).
— 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. It is recommended you
drive to the nearest service center and have the
vehicle serviced immediately.

— Service Forward Collision Warning
(FCW) Light — If Equipped
This warning light will illuminate to indicate
a fault in the Forward Collision Warning
System. Contact an authorized dealer for
service.
Refer to "Forward Collision Warning (FCW)"
in "Safety" for further information.
— Service Stop/Start System Warning
Light — If Equipped
This warning light will illuminate when the
Stop/Start system is not functioning properly
and service is required. Contact an autho -
rized dealer for service.
— Speed Control Fault Warning Light
This warning light will illuminate to indicate
the Speed Control System is not functioning
properly and service is required. Contact an
authorized dealer.
— Sway Bar Fault Warning Light
This light will illuminate when there is a fault
in the sway bar disconnect system.
— Tire Pressure Monitoring System
(TPMS) Warning Light
The warning light switches on and a message
is displayed to indicate that the tire pressure
is lower than the recommended value and/or
that slow pressure loss is occurring. In these
cases, optimal tire duration and fuel
consumption may not be guaranteed.
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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73
Refer to “Starting The Engine” in “Starting
And Operating” for further information.
NOTE:
The “Wait To Start” telltale may not illumi-
nate if the intake manifold temperature is
warm enough.
— Low Diesel Exhaust Emissions Additive
AdBlue® Indicator Light — If Equipped
The Low Diesel Exhaust Emissions Additive
AdBlue® indicator light illuminates when
the AdBlue® (UREA) level is low.
Fill the AdBlue® tank as soon as possible
with at least 1.3 gallons (5 liters) of
AdBlue®.
If filling the tank is done with a remaining
range of AdBlue® in the tank equal to zero,
you may need to wait two minutes before
starting the vehicle.
Refer to “Adding AdBlue®” in “Starting And
Operating” for further information.
— Water In Fuel Indicator Light — If
Equipped
The “Water In Fuel Indicator Light” will illu -
minate when there is water detected in the
fuel filter. If this light remains on, DO NOT start the vehicle before you drain the water
from the fuel filter to prevent engine
damage, and please see an authorized
dealer.
Green Indicator Lights
— Adaptive Cruise Control (ACC) Set With
No Target Detected Indicator Light — If
Equipped
This light will turn on when the Adaptive
Cruise Control is set and there is no target
vehicle detected. Refer to “Adaptive Cruise
Control (ACC) — If Equipped” in “Starting
And Operating” for further information.
— Adaptive Cruise Control (ACC) Set With
Target Light — If Equipped
This will display when the ACC is set and a
target vehicle is detected. Refer to “Adaptive
Cruise Control (ACC) — If Equipped” in
“Starting And Operating” for further informa -
tion.
— 4WD Auto Indicator Light — If
Equipped
This light alerts the driver that the vehicle is
in the four-wheel drive auto mode. The
system will provide power to all four wheels
and shift the power between the front and
rear axles as needed. This will provide
maximum traction in dry and slippery condi -
tions.
— Active Speed Limiter SET Indicator
Light — If Equipped With A Premium
Instrument Cluster
This indicator light will illuminate when the
Active Speed Limiter is on and set to a
specific speed.
Refer to “Active Speed Limiter — If
Equipped” in “Starting And Operating” for
further information.
CAUTION!
The presence of water in the fuel system
circuit may cause severe damage to the
injection system and irregular engine
operation. If the indicator light is
illuminated, contact an authorized dealer
as soon as possible to bleed the system. If
the above indications come on
immediately after refuelling, water has
probably been poured into the tank: switch
the engine off immediately and contact an
authorized dealer.
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77
(Continued)
(Continued)
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 govern -
ment regulations.
If any of these systems require service, the
OBD II system will turn on the Malfunction
Indicator Light (MIL). It will also store diag -
nostic codes and other information to assist
your service technician in making repairs.
Although your vehicle will usually be drive -
able and not need towing, see an authorized
dealer for service as soon as possible.
Onboard Diagnostic System (OBD II)
Cybersecurity
Your vehicle is required to have an Onboard
Diagnostic system (OBD II) and a connection
port to allow access to information related to
the performance of your emissions controls.
Authorized service technicians may need to
access this information to assist with the
diagnosis and service of your vehicle and
emissions system. For further information, refer to “Cybersecu-
rity” in “Multimedia” in your Owner’s
Manual.
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.
WARNING!
ONLY an authorized service technician
should connect equipment to the OBD II
connection port in order to read the VIN,
diagnose, or service your vehicle.
CAUTION! (Continued)
If unauthorized equipment is connected
to the OBD II connection port, such as a
driver-behavior tracking device, it may:
Be possible that vehicle systems, including safety related systems,could be impaired or a loss of vehicle
control could occur that may result in
an accident involving serious injury
or death.
Access, or allow others to access, information stored in your vehicle
systems, including personal informa-
tion.
WARNING! (Continued)
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