2018 JEEP WRANGLER light

SAFETY FEATURES
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) provides
increased vehicle stability and brake perfor-
mance under most braking conditions. The
system automatically prevents wheel lock,
and enhances vehicle control during braking.
The ABS performs a self-check cycle to en-
sure that the ABS is working properly each
time the vehicle is started and driven. During
this self-check, you may hear a slight clicking
sound as well as some related motor noises.
ABS is activated during braking when the
system detects one or more wheels begin to
lock. Road conditions such as ice, snow,
gravel, bumps, railroad tracks, loose debris,
or panic stops may increase the likelihood of
ABS activation(s).
You also may experience the following when
ABS activates:
• The ABS motor noise (it may continue to
run for a short time after the stop).
• The clicking sound of solenoid valves.• Brake pedal pulsations.
• A slight drop of the brake pedal at the end
of the stop.
These are all normal characteristics of ABS.
WARNING!
• The ABS contains sophisticated elec-
tronic equipment that may be suscep-
tible to interference caused by improp-
erly installed or high output radio
transmitting equipment. This interfer-
ence can cause possible loss of anti-lock
braking capability. Installation of such
equipment should be performed by
qualified professionals.
• Pumping of the Anti-Lock Brakes will
diminish their effectiveness and may
lead to a collision. Pumping makes the
stopping distance longer. Just press
firmly on your brake pedal when you
need to slow down or stop.
• The ABS cannot prevent the natural laws
of physics from acting on the vehicle,
nor can it increase braking or steering
efficiency beyond that afforded by the
WARNING!
condition of the vehicle brakes and tires
or the traction afforded.
• The ABS cannot prevent collisions, in-
cluding those resulting from excessive
speed in turns, following another vehicle
too closely, or hydroplaning.
• The capabilities of an ABS equipped
vehicle must never be exploited in a
reckless or dangerous manner that could
jeopardize the user’s safety or the safety
of others.
ABS is designed to function with the OEM
tires. Modification may result in degraded
ABS performance.
Anti-Lock Brake Warning Light
The yellow “Anti-Lock Brake 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 “Anti-Lock Brake Warning Light” re-
mains on or comes on while driving, it indi-
cates that the anti-lock portion of the brake
system is not functioning and that service is
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68

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
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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.
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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.
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