2021 JEEP WRANGLER UNLIMITED engine

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.
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SAFETY
116
(Continued)
NOTE:
After an accident, remember to cycle the
ignition to the STOP (OFF/LOCK) position
and remove the key from the ignition switch
to avoid draining the battery. Carefully check
the vehicle for fuel leaks in the engine
compartment and on the ground near the
engine compartment and fuel tank before
resetting the system and starting the engine.
If there are no fuel leaks or damage to the
vehicle electrical devices (e.g. headlights)
after an accident, reset the system by
following the procedure described below. If
you have any doubt, contact an authorized
dealer.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident
Response System functions after an event,
the ignition switch must be changed from
ignition START or ON/RUN to ignition OFF.
Carefully check the vehicle for fuel leaks in
the engine compartment and on the ground
near the engine compartment and fuel tank
before resetting the system and starting the
engine.
Maintaining Your Air Bag System
WARNING!

Modifications to any part of the air bag
system could cause it to fail when you need
it. You could be injured if the air bag
system is not there to protect you. Do not
modify the components or wiring,
including adding any kind of badges or
stickers to the steering wheel hub trim
cover or the upper passenger side of the
instrument panel. Do not modify the front
bumper, vehicle body structure, or add
aftermarket side steps or running boards.

It is dangerous to try to repair any part of
the air bag system yourself. Be sure to
tell anyone who works on your vehicle
that it has an air bag system.
Do not attempt to modify any part of your
air bag system. The air bag may inflate
accidentally or may not function properly
if modifications are made. Take your
vehicle to an authorized dealer for any air
bag system service. If your seat,
including your trim cover and cushion,
needs to be serviced in any way
(including removal or loosening/
tightening of seat attachment bolts),
take the vehicle to an authorized dealer.
Only manufacturer approved seat
accessories may be used. If it is
necessary to modify the air bag system
for persons with disabilities, contact an
authorized dealer.
WARNING! (Continued)
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135
SAFETY TIPS
Transporting Passengers
NEVER TRANSPORT PASSENGERS IN THE
CARGO AREA.
Exhaust Gas The best protection against carbon monoxide
entry into the vehicle body is a properly
maintained engine exhaust system.
Whenever a change is noticed in the sound of
the exhaust system, when exhaust fumes can
be detected inside the vehicle, or when the
underside or rear of the vehicle is damaged,
have a competent mechanic 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, inspect the exhaust system each
time the vehicle is raised for lubrication or oil
change. Replace as required.
WARNING!
Do not leave children or animals inside
parked vehicles in hot weather. Interior
heat build-up may cause serious injury or
death.
It is extremely dangerous to ride in a
cargo area, inside or outside of a vehicle.
In a collision, people riding in these
areas are more likely to be seriously
injured or killed.
Do not allow people to ride in any area of
your vehicle that is not equipped with
seats and seat belts.
Be sure everyone in your vehicle is in a
seat and using a seat belt properly.
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. To avoid breathing (CO), follow
these safety tips:

Do not run the engine in a closed garage or in
confined areas any longer than needed to
move your vehicle in or out of the area.
If you are required to drive with the trunk/lift-
gate/rear doors open, make sure that all
windows are closed and the climate control
BLOWER switch is set at high speed. DO NOT
use the recirculation mode.

If it is necessary to sit in a parked vehicle
with the engine running, adjust your
heating or cooling controls to force
outside air into the vehicle. Set the
blower at high speed.
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