JEEP WRANGLER 2021 Owner handbook (in English)

required. However, the conventional brake
system will continue to operate normally if
the “Brake System Warning Light” is not on.
If the “Anti-Lock Brake Warning Light” is on,
the brake system should be serviced as soon
as possible to restore the benefits of anti-lock
brakes. If the “Anti-Lock Brake Warning
Light” does not come on when the ignition is
turned to the ON/RUN mode, have the light
repaired as soon as possible.
Electronic Brake Control System
Your vehicle is equipped with an advanced
Electronic Brake Control system (EBC). This
system includes Electronic Brake Force Dis-
tribution (EBD), Brake Assist System (BAS),
Hill Start Assist (HSA), Traction Control Sys-
tem (TCS), Electronic Stability Control
(ESC), and Electronic Roll Mitigation (ERM).
These systems work together to enhance both
vehicle stability and control in various driving
conditions.
Your vehicle may also be equipped with
Trailer Sway Control (TSC) and Hill Descent
Control (HDC).
Electronic Brake Force Distribution (EBD)
This function 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 be-
fore the front axle.
Brake System Warning Light
The red “Brake System Warning Light” will
turn on when the ignition is turned to the
ON/RUN mode and may stay on for as long as
four seconds.
If the “Brake System Warning Light” remains
on or comes on while driving, it indicates that
the brake system is not functioning properly
and that immediate service is required. If the
“Brake System Warning Light” does not
come on when the ignition is turned to the
ON/RUN mode, have the light repaired as
soon as possible.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s
braking capability during emergency braking
maneuvers. The system detects an emer-
gency braking situation by sensing the rate
and amount of brake application and then
applies optimum pressure to the brakes. This
can help reduce braking distances. The BAS
complements the anti-lock brake system
(ABS). Applying the brakes very quickly re-
sults in the best BAS assistance. To receive
the benefit of the system, you must apply
continuous braking pressure during the stop-
ping sequence, (do not “pump” the brakes).
Do not reduce brake pedal pressure unless
braking is no longer desired. Once the brake
pedal is released, the BAS is deactivated.
WARNING!
The Brake Assist System (BAS) cannot
prevent the natural laws of physics from
acting on the vehicle, nor can it increase
the traction afforded by prevailing road
conditions. BAS cannot prevent collisions,
including those resulting from excessive
69

WARNING!
speed in turns, driving on very slippery
surfaces, or hydroplaning. The capabilities
of a BAS-equipped vehicle must never be
exploited in a reckless or dangerous man-
ner, which could jeopardize the user's
safety or the safety of others.
Hill Start Assist (HSA)
The HSA system is designed to mitigate roll
back from a complete stop while on an in-
cline. If the driver releases the brake while
stopped on an incline, HSA will continue to
hold the brake pressure for a short period. If
the driver does not apply the throttle before
this time expires, the system will release
brake pressure and the vehicle will roll down
the hill as normal.
The following conditions must be met in
order for HSA to activate:
• The feature must be enabled.
• The vehicle must be stopped.
• Park brake must be off.• Driver door must be closed.
• The vehicle must be on a sufficient grade.
• The gear selection must match vehicle up-
hill direction (i.e., vehicle facing uphill is in
forward gear; vehicle backing uphill is in
REVERSE gear).
• HSA will work in REVERSE gear and all
forward gears. The system will not activate
if the transmission is in PARK or NEU-
TRAL. For vehicles equipped with a manual
transmission, if the clutch is pressed, HSA
will remain active.
WARNING!
There may be situations where the Hill
Start Assist (HSA) will not activate and
slight rolling may occur, such as on minor
hills or with a loaded vehicle, or while
pulling a trailer. HSA is not a substitute for
active driving involvement. It is always the
driver’s responsibility to be attentive to
distance to other vehicles, people, and
objects, and most importantly brake op-
eration to ensure safe operation of the
vehicle under all road conditions. Your
WARNING!
complete attention is always required
while driving to maintain safe control of
your vehicle. Failure to follow these warn-
ings can result in a collision or serious
personal injury.
Disabling And Enabling HSA
This feature can be turned on or turned off.
To change the current setting using your
instrument cluster display, refer to “Instru-
ment Cluster Display” in “Getting To Know
Your Instrument Panel” for further informa-
tion.
For vehicles not equipped with an instrument
cluster display, perform the following steps:
1. Center the steering wheel (front wheels
pointing straight forward).
2. Shift the transmission into PARK.
3. Apply the parking brake.
4. Start the engine.
5. Rotate the steering wheel slightly more
than one-half turn to the left.
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70

6. Push the “ESC Off” button located in the
lower switch bank below the climate con-
trol four times within 20 seconds. The
“ESC Off Indicator Light” should turn on
and turn off two times.
7. Rotate the steering wheel back to center
and then an additional slightly more than
one-half turn to the right.
8. Turn the ignition to the OFF mode and
then back to ON. If the sequence was
completed properly, the “ESC Off Indica-
tor Light” will blink several times to con-
firm HSA is disabled.
9. Repeat these steps if you want to return
this feature to its previous setting.
Traction Control System (TCS)
This system 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 re-
duce engine power to provide enhanced ac-
celeration and stability. A feature of the TCS,
Brake Limited Differential (BLD), functions
similar to a limited slip differential and con-
trols the wheel spin across a driven axle. Ifone 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 en-
abled even if TCS and ESC are in a reduced
mode.
Electronic Stability Control (ESC)
This system enhances directional control and
stability of the vehicle under various driving
conditions. The ESC corrects for over/under
steering of the vehicle by applying the brake
of the appropriate wheel to assist in counter-
acting the over/under steer condition. Engine
power may also be reduced to help the ve-
hicle 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 po-
sition.• 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),
starts to flash as soon as the tires lose trac-
tion and the ESC system becomes active. The
“ESC Activation/Malfunction Indicator
Light” also flashes when TCS is active. If the
“ESC Activation/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!
• Electronic Stability Control (ESC) can-
not prevent the natural laws of physics
from acting on the vehicle, nor can it
increase the traction afforded by prevail-
ing road conditions. ESC cannot prevent
accidents, including those resulting
from excessive speed in turns, driving on
very slippery surfaces, or hydroplaning.
71

WARNING!
ESC also cannot prevent accidents re-
sulting from loss of vehicle control due
to inappropriate driver input for the con-
ditions. Only a safe, attentive, and skill-
ful driver can prevent accidents. The
capabilities of an ESC equipped vehicle
must never be exploited in a reckless or
dangerous manner which could jeopar-
dize the user’s safety or the safety of
others.
• Vehicle modifications, or failure to prop-
erly maintain your vehicle, may change
the handling characteristics of your ve-
hicle, and may negatively affect the per-
formance of the ESC system. Changes to
the steering system, suspension, brak-
ing system, tire type and size or wheel
size may adversely affect ESC perfor-
mance. Improperly inflated and un-
evenly worn tires may also degrade ESC
performance. Any vehicle modification
or poor vehicle maintenance that re-
duces the effectiveness of the ESC sys-
tem can increase the risk of loss of
WARNING!
vehicle control, vehicle rollover, per-
sonal injury and death.
The ESC system has three available operating
modes in 4H range. The system has one
operating mode in 4L range. Two-wheel drive
vehicles and four-wheel drive vehicles in 2H
range have two operating modes.
4H Range (4WD Models)
ESC On
This is the normal operating mode for ESC in
4H range.
ESC Partial Off
This mode is entered by momentarily pushing
the ESC OFF switch. When in "ESC Partial
Off" mode, the TCS portion 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.
This mode is intended to be used if the
vehicle is in deep snow, sand, or gravel con-
ditions and more wheel spin than ESC would
normally allow is required to gain traction. Toturn ESC on again, momentarily push the
ESC OFF switch. This will restore the normal
“ESC On” mode of operation.
NOTE:
To improve the vehicle’s traction when driving
with snow chains, or starting off in deep
snow, sand, or gravel, it may be desirable to
switch to the "ESC Partial Off" mode by
pushing the ESC OFF switch. Once the situ-
ation requiring ESC to be switched to the
"ESC Partial Off" mode is overcome, turn ESC
back on by momentarily pushing the ESC
OFF switch. This may be done while the
vehicle is in motion.
WARNING!
• When in "ESC Partial Off" mode, the TCS
functionality of ESC, (except for the lim-
ited slip feature described in the TCS
section), has been disabled and the
“ESC Off Indicator Light” will be illumi-
nated. When in "ESC Partial Off" mode,
the engine power reduction feature of
TCS is disabled, and the enhanced ve-
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72

WARNING!
hicle stability offered by the ESC system
is reduced.
• Trailer Sway control (TSC) is disabled
when the ESC system is in the "ESC
Partial Off" mode.
ESC Full Off
This mode is entered by pushing and holding
the ESC OFF switch for five seconds.
In the "ESC Full Off" mode, the engine torque
reduction and stability features are disabled.
Therefore, the enhanced vehicle stability of-
fered by ESC 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.When in "ESC Full Off" mode, ESC and TCS,
except for the Brake Limited Differential
(BLD) feature described in the TCS section,
are turned off until the vehicle reaches an
approximate speed of 40 mph (64 km/h). For
speeds at or exceeding approximately
40 mph (64 km/h) the ESC goes into "ESC
Partial Off". When the vehicle speed drops
below 35 mph (56 km/h), the ESC system
goes back to "ESC Full Off". To turn ESC on
again, momentarily push the ESC OFFswitch. This will restore normal “ESC On”
mode of operation. The "ESC Off Indicator
Light” will always be illuminated when ESC is
in "ESC Partial Off" and "ESC full Off".
WARNING!
With the ESC in "ESC Full Off" mode, the
engine torque reduction and stability fea-
tures offered by ESC and ERM are dis-
abled. In an emergency evasive maneuver,
the ESC and ERM systems will not engage
to assist in maintaining stability. The "ESC
Full Off" mode is intended for off-road use
only.
4L Range (4WD Models)
ESC Full Off
This is the normal operating mode for ESC in
4L range. Whenever the vehicle is started in
4L range, or the transfer case (if equipped) is
shifted from 4H range or NEUTRAL to 4L
range, the ESC system will be in this mode. In
4L range, ESC and TCS, except for the Brake
Limited Differential (BLD) feature described
in the TCS section, are turned off until the
vehicle reaches an approximate speed of
ESC OFF Switch
73

40 mph (64 km/h). For speeds at or exceed-
ing approximately 40 mph (64 km/h) the ESC
goes into "ESC Partial Off" When the vehicle
speed drops below 35 mph (56 km/h), the
ESC system goes back to "ESC Full Off". The
ESC is in "ESC Full Off" at low vehicle speeds
in 4L range so that it will not interfere with
off-road driving, but the ESC function returns
to provide the stability feature at speeds
above 40 mph (64 km/h). The “ESC OFF
Indicator Light” will always be illuminated in
4L range when ESC is in "ESC Full Off" or
"ESC Partial Off".
NOTE:
The “ESC OFF” message will display and an
audible chime will sound when the gear se-
lector is placed in the PARK position from
any other position, and then moved out of the
PARK position. This will occur even if the
message was previously cleared.
WARNING!
With the ESC in "ESC Full Off" mode, the
engine torque reduction and stability fea-
tures offered by ESC and ERM are dis-
WARNING!
abled. In an emergency evasive maneuver,
the ESC and ERM systems will not engage
to assist in maintaining stability. The "ESC
Full Off" mode is intended for off-road use
only.
2H Range (4WD Models) Or 2WD Models
ESC On
This is the normal operating mode for ESC in
2H range and on 2WD vehicles.
ESC Partial Off
When in "ESC Partial Off" mode, the TCS
portion 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.
This mode is intended to be used if the
vehicle is in deep snow, sand, or gravel con-
ditions and more wheel spin than ESC would
normally allow is required to gain traction. To
turn ESC on again, momentarily push the
ESC OFF switch. This will restore the normal
"ESC On" mode of operation.NOTE:
To improve the vehicle’s traction when driving
with snow chains, or starting off in deep
snow, sand, or gravel, it may be desirable to
switch to the "ESC Partial Off" mode by
pushing the "ESC Full Off" switch. Once the
situation requiring ESC to be switched to the
"ESC Partial Off" mode is overcome, turn ESC
back on by momentarily pushing the "ESC
Full Off" switch. This may be done while the
vehicle is in motion.
The ESC will restore to normal ESC On mode
after each key on.
WARNING!
• When in “Partial Off” mode, the TCS
functionality of ESC, (except for the lim-
ited slip feature described in the TCS
section), has been disabled and the
“ESC Off Indicator Light” will be illumi-
nated. When in “Partial Off” mode, the
engine power reduction feature of TCS is
disabled, and the enhanced vehicle sta-
bility offered by the ESC system is re-
duced.
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74

WARNING!
• Trailer Sway Control (TSC) is disabled
when the ESC system is in the "Partial
Off" mode.
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 ignition is turned to
the ON mode. It should go out
with the engine running. If the “ESC
Activation/Malfunction Indicator Light”
comes on continuously with the engine run-
ning, 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 (kilometers) at
speeds greater than 30 mph (48 km/h), see
your authorized dealer as soon as possible to
have the problem diagnosed and corrected.
The “ESC Activation/Malfunction Indicator
Light” (located in the instrument cluster) starts
to flash as soon as the tires lose traction andthe ESC system becomes active. The “ESC
Activation/Malfunction Indicator Light” also
flashes when TCS is active. If the “ESC
Activation/Malfunction Indicator Light” begins
to flash during acceleration, ease up on the
accelerator and apply as little throttle as pos-
sible. Be sure to adapt your speed and driving
to the prevailing road conditions.
NOTE:
• The “ESC Activation/Malfunction Indicator
Light” and the “ESC OFF Indicator Light”
come on momentarily each time the igni-
tion is turned ON.
• Each time the ignition is turned ON, the
ESC system will be on even if it was turned
off previously.
• The ESC system will make buzzing or click-
ing sounds when it is active. This is normal;
the sounds will stop when ESC becomes
inactive following the maneuver that
caused the ESC activation.
The “ESC OFF Indicator Light”
indicates the customer has
elected to have the Electronic
Stability Control (ESC) in a re-
duced mode.
Electronic Roll Mitigation (ERM)
This system 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 vehi-
cle’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, leav-
ing 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.
75

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.
Trailer Sway Control (TSC)
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 excessively swaying trailer is recog-
nized.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
Activation/Malfunction Indicator Light” will
flash, the engine power may be reduced and
you may feel the brakes being applied to
individual 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 TSC activates while driving, slow the
vehicle down, stop at the nearest safe
location, and adjust the trailer load to
eliminate trailer sway.
Hill Descent Control (HDC) — If Equipped
HDC is only intended for low speed off-road
driving. HDC maintains vehicle speed while
descending hills in off-road driving condi-
tions by applying the brakes when necessary.
The symbol indicates the status
of the Hill Descent Control
(HDC) feature. The lamp will be
on solid when HDC is armed.
HDC can only be armed when the
transfer case is in the “4WD LOW” position
and the vehicle speed is less then 30 mph
(48 km/h). If these conditions are not met
while attempting to use the HDC feature, the
HDC indicator light will flash on/off.
When enabled, HDC senses the terrain and acti-
vates when the vehicle is descending a hill. HDC
speed may be adjusted by the driver to suit the
driving conditions. The speed corresponds to the
transmission gear selected.
Gear Approximate HDC Set
Speed
1st 1 mph (1.5 km/h)
2nd 2.5 mph (4 km/h)
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76

Gear Approximate HDC Set
Speed
3rd 4 mph (6.5 km/h)
4th 5.5 mph (9 km/h)
DRIVE 7.5 mph (12 km/h)
REVERSE 1 mph (1.5 km/h)
However, the driver can override HDC opera-
tion by applying the brake to slow the vehicle
down below the HDC control speed. If more
speed is desired during HDC control, the
accelerator pedal will increase vehicle speed
in the usual manner. When either the brake or
the accelerator is released, HDC will control
the vehicle at the original set speed.
Enabling HDC
1. Shift the transfer case into 4WD LOW
range. Refer to “Four-Wheel Drive Opera-
tion” in “Starting and Operating” for fur-
ther information.
2. Push the “Hill Descent” button. The “Hill
Descent Control Indicator Light” in the
instrument cluster will turn on solid.NOTE:
• If the transfer case is not in 4WD LOW
range, the “Hill Descent Control Indica-
tor Light” will flash for five seconds and
HDC will not be enabled.
• If the ESC senses that the brakes are
overheating the “Hill Descent Control
Indicator Light” will flash for five sec-
onds and HDC will become deactivated
until the brakes have cooled.
Disabling HDC
Push the “Hill Descent” button or shift the
transfer case out of 4WD LOW range. The
“Hill Descent Control Indicator” light in the
instrument cluster will turn off.
AUXILIARY DRIVING
SYSTEMS
Tire Pressure Monitor System (TPMS)
The Tire Pressure Monitoring System (TPMS)
will warn the driver of a low tire pressure
based on the vehicle recommended cold
placard pressure.The tire pressure will vary with temperature
by about 1 psi (7.0 kPa) for every 12°F
(6.5°C). This means that when the outside
temperature decreases, the tire pressure will
decrease. Tire pressure should always be set
based on cold inflation tire pressure. This is
defined as the tire pressure after a vehicle
has not been driven for more than three
hours, or driven less than 1 mile (1.6 km)
after a three-hour period. Refer to “Tires” in
“Servicing and Maintenance” for information
on how to properly inflate the vehicle’s tires.
The tire pressure will also increase as the
vehicle is driven; this is normal and there
should be no adjustment for this increased
pressure.
The TPMS will warn the driver of a low tire
pressure if the tire pressure falls below the
low pressure warning threshold for any rea-
son, including low temperature effects, or
natural pressure loss through the tire.
The TPMS will continue to warn the driver of
low tire pressure as long as the condition
exists, and will not turn off until the tire
pressure is at or above recommended cold
placard pressure. Once the “Tire Pressure
77

Monitoring Telltale Light” has been illumi-
nated, the tire pressure must be increased to
the recommended cold placard pressure in
order for the “Tire Pressure Monitoring Tell-
tale Light” to be turned OFF.
NOTE:
When filling warm tires, the tire pressure may
need to be increased up to an additional 4 psi
(30 kPa) above the recommended cold plac-
ard pressure in order to turn the Tire Pressure
Monitoring Telltale Light off.
The system will automatically update and the
“Tire Pressure Monitoring Telltale Light” will
extinguish once the updated tire pressures
have been received. The vehicle may need to
be driven for up to 10 minutes above 15 mph
(24 km/h) to receive this information.
For example, your vehicle may have a recom-
mended cold (parked for more than three
hours) air pressure of 35 psi (241 kPa). If the
ambient temperature is 68°F (20°C) and the
measured tire pressure is 30 psi (207 kPa), a
temperature drop to 20°F (-7°C) will de-
crease the tire pressure to approximately
26 psi (179 kPa). This tire pressure is suffi-
ciently low enough to turn ON the “Tire Pres-sure Monitoring Telltale Light.” Driving the
vehicle may cause the tire pressure to rise to
approximately 30 psi (207 kPa), but the “Tire
Pressure Monitoring Telltale Light” will still
be ON. In this situation, the “Tire Pressure
Monitoring Telltale Light” will turn OFF only
after the tires have been inflated to the vehi-
cle’s recommended cold placard pressure
value.
CAUTION!
• The TPMS has been optimized for the
original equipment tires and wheels.
TPMS pressures and warnings have
been established for the tire size
equipped on your vehicle. Undesirable
system operation or sensor damage may
result when using replacement equip-
ment that is not of the same size, type,
and/or style. The TPM sensor is not de-
signed for use on aftermarket wheels
and may contribute to a poor overall
system performance or sensor damage.
Customers are encouraged to use OEM
wheels to assure proper TPM feature
operation.
CAUTION!
• Using aftermarket tire sealants may
cause the Tire Pressure Monitoring Sys-
tem (TPMS) sensor to become inoper-
able. After using an aftermarket tire
sealant it is recommended that you take
your vehicle to an authorized dealership
to have your sensor function checked.
• After inspecting or adjusting the tire
pressure, always reinstall the valve stem
cap. This will prevent moisture and dirt
from entering the valve stem, which
could damage the Tire Pressure Monitor-
ing Sensor.
NOTE:
• The TPMS is not intended to replace nor-
mal tire care and maintenance, nor to pro-
vide warning of a tire failure or condition.
• The TPMS should not be used as a tire
pressure gauge while adjusting your tire
pressure.
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78