light JEEP GRAND CHEROKEE LIMITED 2019 Workshop Manual

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.
— 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. We recommend you
drive to the nearest service center and have the vehicle
serviced immediately.

CAUTION!
The TPMS has been optimized for the original equip-
ment tires and wheels. TPMS pressures and warning
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.
Aftermarket wheels can cause sensor damage. Using
aftermarket tire sealants may cause the Tire Pressure
Monitoring System (TPMS) sensor to become inoper-
able. After using an aftermarket tire sealant it is
recommended that you take your vehicle to your au-
thorized dealer to have your sensor function checked.
Yellow Indicator Lights

— 4WD Low Indicator Light — If Equipped
This light alerts the driver that the vehicle is in the
four-wheel drive LOW mode. The front and rear drive-
shafts are mechanically locked together forcing the front
and rear wheels to rotate at the same speed. Low range
provides a greater gear reduction ratio to provide increased
torque at the wheels.
Refer to “Four-Wheel Drive Operation — If Equipped” in
“Starting And Operating” for further information on four-
wheel drive operation and proper use.

— Park/Headlight On Indicator Light
This indicator light will illuminate when the park lights or
headlights are turned on.

— LaneSense Indicator Light — If Equipped
When the LaneSense system is ON, but not armed, the
LaneSense indicator light illuminates solid white. This
occurs when only left, right, or neither lane line has been
detected. If a single lane line is detected, the system is
ready to provide only visual warnings if an unintentional
lane departure occurs on the detected lane line.
Refer to “LaneSense — If Equippedin “Starting And
Operating” for further information.

If any of these systems require service, the OBD II system
will turn on the Malfunction Indicator Light (MIL). It will
also store diagnostic codes and other information to assist
your service technician in making repairs. Although your
vehicle will usually be drivable and not need towing, see
an authorized dealer for service as soon as possible.

EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass an
inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.For states that require an Inspection and Main-
tenance (I/M), this check verifies the “Malfunc-
tion Indicator Light (MIL)” is functioning and is
not on when the engine is running, and that the
OBD II system is ready for testing.
Normally, the OBD II system will be ready. The OBD II
system may notbe ready if your vehicle was recently
serviced, recently had a dead battery or a battery replace-
ment. If the OBD II system should be determined not ready
for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition actuated test, which you
can use prior to going to the test station. To check if your
vehicle’s OBD II system is ready, you must do the follow-
ing:
1. Cycle the ignition switch to the ON position, but do not crank or start the engine. NOTE:
If you crank or start the engine, you will have to
start this test over.
2. As soon as you cycle the ignition switch to the ON position, you will see the “Malfunction Indicator Light
(MIL)” symbol come on as part of a normal bulb check.
3. Approximately 15 seconds later, one of two things will happen:
• The MIL will flash for about ten seconds and then return
to being fully illuminated until you turn OFF the igni-
tion or start the engine. This means that your vehicle’s
OBD II system is not readyand you should notproceed
to the I/M station.
• The MIL will not flash at all and will remain fully
illuminated until you place the ignition in the off posi-
tion or start the engine. This means that your vehicle’s
OBD II system is readyand you can proceed to the I/M
station.
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GETTING TO KNOW YOUR INSTRUMENT PANEL 163

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 activa-
tion(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 Warn-
ing 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 167

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.