engine JEEP WRANGLER UNLIMITED 2021 Owner handbook (in English)

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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GETTING TO KNOW YOUR INSTRUMENT PANEL
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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SAFETY
80
Electronic Brake Force Distribution (EBD)
The Electronic Brake Force Distribution
(EBD) manages the distribution of the
braking torque between the front and rear
axles by limiting braking pressure to the rear
axle. This is done to prevent overslip of the
rear wheels to avoid vehicle instability, and
to prevent the rear axle from entering ABS
before the front axle.
Electronic Roll Mitigation (ERM)
Electronic Roll Mitigation (ERM) anticipates
the potential for wheel lift by monitoring the
driver’s steering wheel input and the speed
of the vehicle. When ERM determines that
the rate of change of the steering wheel
angle and vehicle’s speed are sufficient to
potentially cause wheel lift, it then applies
the appropriate brake and may also reduce
engine power to lessen the chance that
wheel lift will occur. ERM can only reduce
the chance of wheel lift occurring during
severe or evasive driving maneuvers; it
cannot prevent wheel lift due to other
factors, such as road conditions, leaving the
roadway, or striking objects or other vehicles.NOTE:
ERM is disabled anytime the ESC is in “Full
Off” mode (if equipped). Refer to “Electronic
Stability Control (ESC)” in this section for a
complete explanation of the available ESC
modes.
Electronic Stability Control (ESC)
Electronic Stability Control (ESC) enhances
directional control and stability of the
vehicle under various driving conditions.
ESC corrects for oversteering or under
-
steering of the vehicle by applying the brake
of the appropriate wheel(s) to assist in coun -teracting the oversteer or understeer condi
-
tion. Engine power may also be reduced to
help the vehicle maintain the desired path.
ESC uses sensors in the vehicle to determine
the vehicle path intended by the driver and
compares it to the actual path of the vehicle.
When the actual path does not match the
intended path, ESC applies the brake of the
appropriate wheel to assist in counteracting
the oversteer or understeer condition.
Oversteer — when the vehicle is turning
more than appropriate for the steering
wheel position.
Understeer — when the vehicle is turning
less than appropriate for the steering
wheel position.
The “ESC Activation/Malfunction Indicator
Light” located in the instrument cluster will
start to flash as soon as the ESC system
becomes active. The “ESC Activation/
Malfunction Indicator Light” also flashes
when the TCS is active. If the “ESC Activa -
tion/Malfunction Indicator Light” begins to
flash during acceleration, ease up on the
accelerator and apply as little throttle as
possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
WARNING!
Many factors, such as vehicle loading,
road conditions and driving conditions,
influence the chance that wheel lift or
rollover may occur. ERM cannot prevent all
wheel lift or roll overs, especially those
that involve leaving the roadway or striking
objects or other vehicles. The capabilities
of an ERM-equipped vehicle must never
be exploited in a reckless or dangerous
manner which could jeopardize the user's
safety or the safety of others.
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SAFETY
82
(Continued)
Full Off — If Equipped

The “Full Off” mode is intended for off-highway or
off-road use only and should not be used on any
public roadways. In this mode, TCS and ESC
features are turned off. To enter the “Full Off”
mode, push and hold the “ESC OFF” switch for
five seconds while the vehicle is stopped with the
engine running. After five seconds, a chime will
sound, the “ESC OFF Indicator Light” will illumi-
nate, and the “ESC OFF” message will display in
the instrument cluster. To turn ESC On again,
momentarily push the “ESC OFF” switch.
NOTE:
System may switch from ESC “Full Off” to
“Partial Off” mode when vehicle exceeds a
predetermined speed. When the vehicle
speed slows below the predetermined speed
the system will return to ESC “Full Off”.
ESC modes may also be affected by drive
modes (if equipped).
ESC Activation/Malfunction Indicator Light
And ESC OFF Indicator Light

The “ESC Activation/Malfunction
Indicator Light” in the instrument
cluster will come on when the igni
-
tion is turned to the “ESC On” mode.
It should go out with the engine running. If the
“ESC Activation/Malfunction Indicator Light”
comes on continuously with the engine
running, a malfunction has been detected in
the ESC system. If this light remains on after
several ignition cycles, and the vehicle has
been driven several miles (km) at speeds
greater than 30 mph (48 km/h), see an autho -
rized dealer as soon as possible to have the
problem diagnosed and corrected.

WARNING!

When in “Partial Off” mode, the TCS func -
tionality of ESC, (except for the limited slip
feature described in the TCS section), has
been disabled and the “ESC Off Indicator
Light” will be illuminated. When in
“Partial Off” mode, the engine power
reduction feature of TCS is disabled, and
the enhanced vehicle stability offered by
the ESC system is reduced.

Trailer Sway control (TSC) is disabled
when the ESC system is in the “Partial
Off” mode.
WARNING!
In the ESC “Full Off” mode, the engine
torque reduction and stability features
are disabled. Therefore, enhanced
vehicle stability offered by the ESC
system is unavailable. In an emergency
evasive maneuver, the ESC system will
not engage to assist in maintaining
stability. ESC “Full Off” mode is
intended for off-highway or off-road use
only.
The Electronic Stability Control (ESC)
cannot prevent the natural laws of
physics from acting on the vehicle, nor
can it increase the traction afforded by
prevailing road conditions. ESC cannot
prevent all accidents, including those
resulting from excessive speed in turns,
driving on very slippery surfaces, or
hydroplaning. ESC also cannot prevent
collisions.
WARNING! (Continued)
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SAFETY
86
Towing With HSA
HSA will also provide assistance to mitigate
roll back while towing a trailer.
Ready Alert Braking (RAB)
Ready Alert Braking (RAB) may reduce the
time required to reach full braking during
emergency braking situations. It anticipates
when an emergency braking situation may
occur by monitoring how fast the throttle is
released by the driver. The Electronic Brake
Control (EBC) system will prepare the brake
system for a panic stop.
Rain Brake Support (RBS)
Rain Brake Support (RBS) may improve
braking performance in wet conditions. It
will periodically apply a small amount of
brake pressure to remove any water buildup
on the front brake rotors. It functions when
the windshield wipers are in LO or HI speed.
When RBS is active, there is no notification
to the driver and no driver interaction is
required.
Trailer Sway Control (TSC)
Trailer Sway Control (TSC) uses sensors in
the vehicle to recognize an excessively
swaying trailer and will take the appropriate
actions to attempt to stop the sway. TSC will
become active automatically once an exces-
sively swaying trailer is recognized.

NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda-
tions. Refer to “Trailer Towing” in “Starting
And Operating” for further information.

When TSC is functioning, the “ESC Activa -
tion/Malfunction Indicator Light” will flash,
the engine power may be reduced and you
may feel the brakes being applied to indi -
vidual wheels to attempt to stop the trailer
from swaying. TSC is disabled when the ESC
system is in the “Partial Off” or “Full Off”
modes.
WARNING!
If you use a trailer brake controller with
your trailer, the trailer brakes may be
activated and deactivated with the brake
switch. If so, there may not be enough
brake pressure to hold both the vehicle
and the trailer on a hill when the brake
pedal is released. In order to avoid
rolling down an incline while resuming
acceleration, manually activate the
trailer brake or apply more vehicle brake
pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the
transmission in PARK (P).
Failure to follow these warnings can
result in a collision or serious personal
injury. WARNING!
If TSC activates while driving, slow the
vehicle down, stop at the nearest safe
location, and adjust the trailer load to
eliminate trailer sway.
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87
Traction Control System (TCS)

The Traction Control System (TCS) monitors the
amount of wheel spin of each of the driven
wheels. If wheel spin is detected, the TCS may
apply brake pressure to the spinning wheel(s) and/
or reduce engine power to provide enhanced
acceleration and stability. A feature of the TCS,
Brake Limited Differential (BLD), functions
similar to a limited slip differential and controls
the wheel spin across a driven axle. If one wheel
on a driven axle is spinning faster than the other,
the system will apply the brake of the spinning
wheel. This will allow more engine torque to be
applied to the wheel that is not spinning. BLD
may remain enabled even if TCS and Electronic
Stability Control (ESC) are in a reduced mode.

AUXILIARY DRIVING
SYSTEMS
Blind Spot Monitoring (BSM) — If
Equipped
The Blind Spot Monitoring (BSM) system
uses two radar-based sensors, located inside
the taillights, to detect highway licensable
vehicles (automobiles, trucks, motorcycles,
etc.) that enter the blind spot zones from the
rear/front/side of the vehicle.Rear Detection Zones

When the vehicle is started, the BSM warning
light will momentarily illuminate in both outside
rear view mirrors to let the driver know that the
system is operational. The BSM system sensors
operate when the vehicle is in any forward gear or
REVERSE (R) and enters standby mode when the
vehicle is in PARK (P).
The BSM detection zone covers approximately
one lane width on both sides of the vehicle, 12 ft
(3.8 m). The zone length starts at the outside rear
view mirror and extends approximately 10 ft
(3 m) beyond the rear bumper of the vehicle. The
BSM system monitors the detection zones on both
sides of the vehicle when the vehicle speed
reaches approximately 6 mph (10 km/h) or higher and will alert the driver of vehicles in these areas.
NOTE:
The BSM system DOES NOT alert the
driver about rapidly approaching vehicles
that are outside the detection zones.
The BSM system detection zone DOES
NOT change if your vehicle is towing a
trailer. Therefore, visually verify the adja-
cent lane is clear for both your vehicle and
trailer before making a lane change. If the
trailer or other object (i.e., bicycle, sports
equipment) extends beyond the side of
your vehicle, this may result in the BSM
warning light remaining illuminated the
entire time the vehicle is in a forward gear.
The Blind Spot Monitoring (BSM) system
may experience drop outs (blinking on and
off) of the side mirror Warning Indicator
lamps when a motorcycle or any small
object remains at the side of the vehicle
for extended periods of time (more than a
couple of seconds).
The area on taillights, where the radar
sensors are located, must remain free of
snow, ice, and dirt/road contamination so
that the BSM system can function properly.
Do not block the taillights where the radar
sensors are located with foreign objects
(bumper stickers, bicycle racks, etc.).
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105
Air Bag Warning Light
The Occupant Restraint Controller
(ORC) monitors the readiness of the
electronic parts of the air bag
system whenever the ignition
switch is in the START or ON/RUN position.
If the ignition switch is in the OFF position or
in the ACC position, the air bag system is not
on and the air bags will not inflate.
The ORC contains a backup power supply
system that may deploy the air bag system
even if the battery loses power or it becomes
disconnected prior to deployment.
The ORC turns on the Air Bag Warning Light
in the instrument panel for approximately
four to eight seconds for a self-check when
the ignition switch is first in the ON/RUN
position. After the self-check, the Air Bag
Warning Light will turn off. If the ORC
detects a malfunction in any part of the
system, it turns on the Air Bag Warning
Light, either momentarily or continuously. A
single chime will sound to alert you if the
light comes on again after initial startup.
The ORC also includes diagnostics that will
illuminate the instrument panel Air Bag
Warning Light if a malfunction is detected that
could affect the air bag system. The diagnos
-
tics also record the nature of the malfunction.
While the air bag system is designed to be
maintenance free, if any of the following
occurs, have an authorized dealer service the
air bag system immediately.

The Air Bag Warning Light does not come on
during the four to eight seconds when the igni -
tion switch is first in the ON/RUN position.

The Air Bag Warning Light remains on
after the four to eight-second interval.
The Air Bag Warning Light comes on inter -
mittently or remains on while driving.
NOTE:
If the speedometer, tachometer, or any
engine related gauges are not working, the
Occupant Restraint Controller (ORC) may
also be disabled. In this condition the air
bags may not be ready to inflate for your
protection. Have an authorized dealer service
the air bag system immediately.
Redundant Air Bag Warning Light
If a fault with the Air Bag Warning
Light is detected, which could
affect the Supplemental Restraint
System (SRS), the Redundant Air
Bag Warning Light will illuminate on the
instrument panel. The Redundant Air Bag
Warning Light will stay on until the fault is
cleared. In addition, a single chime will
sound to alert you that the Redundant Air
Bag Warning Light has come on and a fault
has been detected. If the Redundant Air Bag
Warning Light comes on intermittently or
remains on while driving have an authorized
dealer service the vehicle immediately.
WARNING!
Ignoring the Air Bag Warning Light in your
instrument panel could mean you won’t
have the air bag system to protect you in a
collision. If the light does not come on as
a bulb check when the ignition is first
turned on, stays on after you start the
vehicle, or if it comes on as you drive, have
an authorized dealer service the air bag
system immediately.
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115
As the air bags deflate, you may see some
smoke-like particles. The particles are a
normal by-product of the process that
generates the non-toxic gas used for air
bag inflation. These airborne particles may
irritate the skin, eyes, nose, or throat. If
you have skin or eye irritation, rinse the
area with cool water. For nose or throat irri-
tation, move to fresh air. If the irritation
continues, see your doctor. If these parti -
cles settle on your clothing, follow the
garment manufacturer’s instructions for
cleaning.
Do not drive your vehicle after the air bags
have deployed. If you are involved in another
collision, the air bags will not be in place to
protect you. NOTE:
Air bag covers may not be obvious in the
interior trim, but they will open during air
bag deployment.

After any collision, the vehicle should be
taken to an authorized dealer immediately.

Enhanced Accident Response System
In the event of an impact, if the communica
-
tion network remains intact, and the power
remains intact, depending on the nature of
the event, the Occupant Restraint Controller
(ORC) will determine whether to have the
Enhanced Accident Response System
perform the following functions:
Cut off fuel to the engine (If Equipped)
Cut off battery power to the electric motor
(If Equipped)
Flash hazard lights as long as the battery
has power
Turn on the interior lights, which remain
on as long as the battery has power or for
15 minutes from the intervention of the
Enhanced Accident Response System.
Unlock the power door locks. Your vehicle may also be designed to perform
any of these other functions in response to
the Enhanced Accident Response System:
Turn off the Fuel Filter Heater, Turn off
the HVAC Blower Motor, Close the HVAC
Circulation Door
Cut off battery power to the:
Engine
Electric Motor (if equipped)
Electric power steering
Brake booster
Electric park brake
Automatic transmission gear selector
Horn
Front wiper
Headlamp washer pump
WARNING!
Deployed air bags and seat belt
pretensioners cannot protect you in
another collision. Have the air bags, seat
belt pretensioners, and the seat belt
retractor assemblies replaced by an
authorized dealer immediately. Also, have
the Occupant Restraint Controller System
serviced as well.
2020_JEEP_JL_WRANGLER_UG_RHD_UK.book Page 115