2012 JEEP WRANGLER brake light

When the parking brake is applied with the ignition
switch ON, the “Brake Warning Light” in the instrument
cluster will illuminate.NOTE:
•When the parking brake is applied and the automatic
transmission is placed in gear, the “Brake Warning
Light” will flash. If vehicle speed is detected, a chime
will sound to alert the driver. Fully release the parking
brake before attempting to move the vehicle.
•This light only shows that the parking brake is ap-
plied. It does not show the degree of brake application.
When parking on a hill, it is important to turn the front
wheels toward the curb on a downhill grade and away
from the curb on an uphill grade. For vehicles equipped
with an automatic transmission, apply the parking brake
before placing the shift lever in PARK, otherwise the load
on the transmission locking mechanism may make it
difficult to move the shift lever out of PARK. The parking
brake should always be applied whenever the driver is
not in the vehicle.
Parking Brake
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CAUTION!
If the “Brake Warning Light” remains on with the
parking brake released, a brake system malfunction
is indicated. Have the brake system serviced by an
authorized dealer immediately.
ANTI-LOCK BRAKE SYSTEM
The Anti-Lock Brake System (ABS) is designed to aid the
driver in maintaining vehicle control under adverse
braking conditions. The system operates with a separate
computer to modulate hydraulic pressure to prevent
wheel lock-up and help avoid skidding on slippery
surfaces.
All vehicle wheels and tires must be the same size and
type, and tires must be properly inflated to produce
accurate signals for the computer.
WARNING!
Significant over or under-inflation of tires, or mixing
sizes of tires or wheels on the vehicle can lead to loss
of braking effectiveness.
The Anti-Lock Brake System conducts a low speed self-
test at about 12 mph (20 km/h). If for any reason your
foot is on the brake when the vehicle reaches 12 mph
(20 km/h), this check will be delayed until 25 mph
(40 km/h).
The Anti-Lock Brake System pump motor runs during
the self-test, and during an ABS stop, to provide the
regulated hydraulic pressure. The motor pump makes a
low humming noise during operation; this is normal.
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the level of brake pressure the driver applied for a short
period of time after the driver takes their foot off of the
brake pedal. If the driver does not apply the throttle
during this short period of time, the system will release
brake pressure and the vehicle will roll down the hill. The
system will release brake pressure in proportion to
amount of throttle applied as the vehicle starts to move in
the intended direction of travel.
WARNING!
If the clutch pedal (manual transmission only) re-
mains pressed during the application of the throttle,
the HSA will disengage allowing the vehicle to roll
down the incline. This could cause a collision with
another vehicle or object. To avoid this, do not apply
throttle while pressing the clutch pedal until you are
ready to release the clutch. Always remember the
driver is responsible for braking the vehicle.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped
•Vehicle must be on an 8% or greater incline (3% for
manual transmission equipped vehicles)
•Gear selection matches vehicle uphill direction (i.e.,
vehicle facing uphill is in forward gear; vehicle back-
ing uphill is in REVERSE gear).
WARNING!
There may be situations on minor hills (i.e., less than
8%), with a loaded vehicle, or while pulling a trailer
where the system will not activate and slight rolling
may occur, which could cause a collision with an-
other vehicle or object. Always remember the driver
is responsible for braking the vehicle.
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(manual transmission) with wheels straight. Apply park-
ing brake on manual transmission vehicle.
2. Start the engine.
3. With the engine running, the brake applied, and the
clutch out, rotate the steering wheel 180° counterclock-
wise from center.
4. Press the ESC OFF switch four times within twenty
seconds.
5. Rotate the steering wheel 360° clockwise (180° clock-
wise from center).
6. Cycle ignition switch OFF then ON.
7. If the sequence was completed properly, the “ESC
Activation/Malfunction Indicator Light” will blink sev-
eral times to confirm HSA is off.
Steps 1-7 must be completed within 90 seconds to turn off
HSA. Repeat steps 1-7 to re-enable HSA functionality.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 applies the
appropriate brake and may reduce engine power to lessen
the chance that wheel lift will occur. ERM will only inter-
vene during very severe or evasive driving maneuvers.
Electronic Roll Mitigation (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 road-
way or striking objects or other vehicles.
NOTE:Anytime the ESC system is in the “Full Off”
mode, ERM is disabled. Refer to Electronic Stability
Control (ESC) for a complete explanation of the available
ESC modes.
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WARNING!
Many factors, such as vehicle loading, road conditions
and driving conditions, influence the chance that
wheel lift or rollover may occur. Electronic Roll Miti-
gation (ERM) cannot prevent all wheel lift or rollovers,
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.
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 apply-
ing the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine
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 appro-
priate 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” (lo-
cated in the instrument cluster), starts to flash as soon as
the tires lose traction 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 ac-
celeration, 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.5
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•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 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
Electronic Stability Control (ESC) is off.
Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize an exces-
sively swaying trailer and will take the appropriate
actions to attempt to stop the sway. The system may
reduce engine power and apply the brake of the appro-
priate wheel(s) to counteract the sway of the trailer. TSC
will become active automatically once an excessively swaying trailer is recognized. No driver action is re-
quired. Note that TSC cannot stop all trailers from
swaying. Always use caution when towing a trailer and
follow the tongue weight recommendations. 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
ESP 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.
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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 conditions 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 attempt-
ing to use the HDC feature, the HDC indicator light will
flash on/off.
When enabled, HDC senses the terrain and activates
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)
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 operation 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.
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the fluid at approximately 80° F (27° C). If the fluid level
is correctly established at 80° F (27° C), it should be
between the HOT (upper) reference holes when the
transmission reaches 180° F (82° C). Remember it is best
to check the level at the normal operating temperature.
CAUTION!
Be aware that if the fluid temperature is below 50° F
(10° C), it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough to
produce an accurate reading.
7. Check for leaks. Release the parking brake.
NOTE: To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
certain that the dipstick cap is properly reseated. It is normal for the dipstick cap to spring back slightly from
its fully seated position, as long as its seal remains
engaged in the dipstick tube.
Hydraulic Clutch Fluid – Manual Transmission
The clutch hydraulic system is fed by a segregated
volume of fluid within the brake system master cylinder
reservoir. In the event of leakage or wear, use only
manufacturer’s recommended brake fluid, refer to “Flu-
ids, Lubricants, and Genuine Parts” in “Maintaining Your
Vehicle” for further information.
Manual Transmission – If Equipped
Selection Of Lubricant
Use only manufacturer’s recommended manual trans-
mission fluid. Refer to “Fluids, Lubricants, and Genuine
Parts” in “Maintaining Your Vehicle” for further
information.7
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