service JEEP WRANGLER JK 2019 Owners Manual

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.

— Engine Check/Malfunction Indicator Warning
Light (MIL)
The Engine Check/Malfunction Indicator Light (MIL) is a
part of an Onboard Diagnostic System called OBD II that
monitors engine and automatic transmission control sys-
tems. The light will illuminate when the ignition is in the
ON/RUN position before engine start. If the bulb does not
come on when turning the ignition switch from OFF to
ON/RUN, have the condition checked promptly.
Certain conditions, such as a loose or missing gas cap, poor
quality fuel, etc., may illuminate the light after engine start.
The vehicle should be serviced if the light stays on through
several typical driving styles. In most situations, the ve-
hicle will drive normally and will not require towing.
When the engine is running, the MIL may flash to alert
serious conditions that could lead to immediate loss of
power or severe catalytic converter damage. The vehicle
should be serviced as soon as possible if this occurs.

CAUTION!(Continued)
•If the MIL is flashing while the vehicle is running,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Onboard Diagnostic System (OBD II) Cybersecurity
Your vehicle is required to have an Onboard Diagnostic
system (OBD II) and a connection port to allow access to
information related to the performance of your emissions
controls. Authorized service technicians may need to ac-
cess this information to assist with the diagnosis and
service of your vehicle and emissions system.

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 “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 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), 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 driv-
ing 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 before the front axle.
5
SAFETY 205

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 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 nolonger desired. Once the brake pedal is released, the BAS is
deactivated.

9. If the air bag system in this vehicle needs to be modifiedto accommodate a disabled person, refer to the “Cus-
tomer Assistance” section for customer service contact
information.

WARNING!(Continued)
the fully upright and locked position when occupied.
If the rear seatback is not fully upright and locked and
the rear center lap/shoulder belt can be pulled out of
the retractor, immediately take the vehicle to your
authorized dealer for service. Failure to follow this
warning could result in serious injury or death.
Lap/Shoulder Belt Untwisting Procedure
Use the following procedure to untwist a twisted lap/
shoulder belt.
1. Position the latch plate as close as possible to the anchor
point.
2. At about 6 to 12 inches (15 to 30 cm) above the latch plate, grasp and twist the seat belt webbing 180 degrees
to create a fold that begins immediately above the latch
plate.
3. Slide the latch plate upward over the folded webbing. The folded webbing must enter the slot at the top of the
latch plate.
4. Continue to slide the latch plate up until it clears the folded webbing and the seat belt is no longer twisted.
Adjustable Upper Shoulder Belt Anchorage
In the driver and front passenger seats, the top of the
shoulder belt can be adjusted upward or downward to
position the seat belt away from your neck. Push or
squeeze the anchorage button to release the anchorage, and
move it up or down to the position that serves you best.

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.
Front Air Bags
This vehicle has front air bags and lap/shoulder belts for
both the driver and front passenger. The front air bags are
a supplement to the seat belt restraint systems. The driver
front air bag is mounted in the center of the steering wheel.
The passenger front air bag is mounted in the instrument
panel, above the glove compartment. The words “SRS
AIRBAG” or “AIRBAG” are embossed on the air bag
covers.

CAUTION!
Prolonged operation of the steering system at the end
of the steering wheel travel will increase the steering
fluid temperature and it should be avoided when
possible. Damage to the power steering pump may
occur.
Power Steering Fluid Check
Checking the power steering fluid level at a defined service
interval is not required. The fluid should only be checked
if a leak is suspected, abnormal noises are apparent,
and/or the system is not functioning as anticipated. Coor-
dinate inspection efforts through your authorized dealer.

•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
• Inspect the radiator for mud and debris and clean as
required.
• Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
• Check for accumulations of plants or brush. These things
could be a fire hazard. They might hide damage to fuel
lines, brake hoses, axle pinion seals, and propeller shafts.
• After extended operation in mud, sand, water, or similar
dirty conditions, have the radiator, fan, brake rotors,
wheels, brake linings, and axle yokes inspected and
cleaned as soon as possible.