brake light JEEP GRAND CHEROKEE LIMITED 2018 Owners Manual

If the light remains on when the parking brake has been
disengaged, and the fluid level is at the full mark on the
master cylinder reservoir, it indicates a possible brake
hydraulic system malfunction or that a problem with the
Brake Booster has been detected by the Anti-Lock Brake
System (ABS) / Electronic Stability Control (ESC) system.
In this case, the light will remain on until the condition has
been corrected. If the problem is related to the brake
booster, the ABS pump will run when applying the brake,
and a brake pedal pulsation may be felt during each stop.
The dual brake system provides a reserve braking capacity
in the event of a failure to a portion of the hydraulic
system. A leak in either half of the dual brake system is
indicated by the Brake Warning Light, which will turn on
when the brake fluid level in the master cylinder has
dropped below a specified level.
The light will remain on until the cause is corrected.
NOTE:The light may flash momentarily during sharp
cornering maneuvers, which change fluid level conditions.
The vehicle should have service performed, and the brake
fluid level checked.
If brake failure is indicated, immediate repair is necessary.

SAFETY FEATURES
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) provides increased
vehicle stability and brake performance under most brak-
ing conditions. The system automatically prevents wheel
lock, and enhances vehicle control during braking.
The ABS performs a self-check cycle to ensure 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!(Continued)
•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. Modifica-
tion 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” remains on or
comes on while driving, it indicates that the anti-lock
portion of the brake system is not functioning and that
service is required. However, the conventional brake sys-
tem will continue to operate normally if the “Anti-Lock
Brake Warning Light” is 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 Elec-
tronic Brake Force Distribution (EBD), Anti-Lock Brake
System (ABS), Brake Assist System (BAS), Hill Start Assist
(HSA), Traction Control System (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), Ready Alert Braking (RAB), Rain Brake
Support (RBS), Dynamic Steering Torque (DST), Hill De-
scent Control (HDC), and Selec-Speed Control (SSC).
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 before 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.
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SAFETY 165

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 re-
quired. 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 sys-
tem detects an emergency 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
results in the best BAS assistance. To receive the benefit of
the system, you must apply continuous braking pressure
during the stopping 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.

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-halfturn to the left.
6. Push the “ESC Off” button located in the lower switch bank below the climate control 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
Indicator Light” will blink several times to confirm HSA
is disabled.
9. Repeat these steps if you want to return this feature to its previous setting.
Towing With HSA
HSA will also provide assistance to mitigate roll back while
towing a trailer.

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 ESC are in a reduced mode.
Electronic Stability Control (ESC)
This system enhances directional control and stability of
the vehicle under various driving conditions. ESC corrects
for oversteering or understeering of the vehicle by apply-
ing the brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer condition. En-
gine 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 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.

•The ESC system will make buzzing or clicking 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 Sta-
bility Control (ESC) in a reduced 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 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.
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SAFETY 173

NOTE:TSC cannot stop all trailers from swaying. Always
use caution when towing a trailer and follow the trailer
tongue weight recommendations. Refer to “Trailer Tow-
ing” 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!(Continued)
•ALWAYS make sure objects cannot fall or slide into
the driver ’s side floor area when the vehicle is
moving. Objects can become trapped under accelera-
tor, brake, or clutch pedals and could cause a loss of
vehicle control.
• NEVER place any objects under the floor mat (e.g.,
towels, keys, etc.). These objects could change the
position of the floor mat and may cause interference
with the accelerator, brake, or clutch pedals.
• If the vehicle carpet has been removed and re-
installed, always properly attach carpet to the floor
and check the floor mat fasteners are secure to the
vehicle carpet. Fully depress each pedal to check for
interference with the accelerator, brake, or clutch
pedals then re-install the floor mats.
• It is recommended to only use mild soap and water
to clean your floor mats. After cleaning, always check
your floor mat has been properly installed and is
secured to your vehicle using the floor mat fasteners
by lightly pulling mat.
Periodic Safety Checks You Should Make Outside
The Vehicle
Tires
Examine tires for excessive tread wear and uneven wear
patterns. Check for stones, nails, glass, or other objects
lodged in the tread or sidewall. Inspect the tread for cuts
and cracks. Inspect sidewalls for cuts, cracks, and bulges.
Check the wheel nuts for tightness. Check the tires (includ-
ing spare) for proper cold inflation pressure.
Lights
Have someone observe the operation of brake lights and
exterior lights while you work the controls. Check turn
signal and high beam indicator lights on the instrument
panel.
Door Latches
Check for proper closing, latching, and locking.
Fluid Leaks
Check area under the vehicle after overnight parking for fuel,
coolant, oil, or other fluid leaks. Also, if gasoline fumes are
detected or if fuel, or brake fluid leaks are suspected. The
cause should be located and corrected immediately.
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SAFETY 247

If you stall or begin to lose forward motionwhile
climbing a steep hill, allow your vehicle to come to a stop
and immediately apply the brakes. Restart the engine, and
shift into REVERSE. Back slowly down the hill, allowing
the compression braking of the engine to help regulate
your speed. If the brakes are required to control vehicle
speed, apply them lightly and avoid locking or skidding
the tires.