2008 JEEP LIBERTY brake

Two additional electronic brake control system options
are HDC (Hill Descent Control) and TSC (Trailer Sway
Control). Your vehicle may be equipped with one or both
of these options.
ABS (Anti-Lock Brake System)
This system aids the driver in maintaining vehicle control
under adverse braking conditions. The system controls
hydraulic brake pressure to prevent wheel lock-up to
help avoid skidding on slippery surfaces during braking.
Refer to ªAnti-Lock Brake Systemº in Section 5 of this
manual for more information about ABS.
WARNING!
ABS (Anti-Lock Brake System) cannot prevent the
natural laws of physics from acting on the vehicle,
nor can it increase the traction afforded by prevailing
road conditions. ABS cannot prevent accidents, in-
cluding those resulting from excessive speed in
turns, driving on very slippery surfaces, or hydro-
planing. Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of an ABS-
equipped vehicle must never be exploited in a reck-
less or dangerous manner, which could jeopardize
the user's safety or the safety of others.
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TCS (Traction Control System)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system 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.
This feature remains active even if TCS and ESP are in the
ªPartial Offº mode or the ªFull Offº mode. Refer to ªESP
(Electronic Stability Program)º in this section for more
information.
BAS (Brake Assist System)
The BAS is designed to optimize the vehicle's braking
capability during emergency braking maneuvers. The
system detects an emergency braking situation by sens-
ing 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 brak-
ing pressure during the stopping sequence, (do not
ªpumpº the brakes). Do not reduce brake pedal pressure
unless braking is no longer desired. Once the brake pedal
is released, the BAS is deactivated.
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WARNING!
BAS (Brake Assist System) cannot prevent the natu-
ral laws of physics from acting on the vehicle, nor can
it increase the traction afforded by prevailing road
conditions. BAS cannot prevent accidents, including
those resulting from excessive speed in turns, driving
on very slippery surfaces, or hydroplaning. Only a
safe, attentive, and skillful driver can prevent acci-
dents. The capabilities of a BAS-equipped vehicle
must never be exploited in a reckless or dangerous
manner, which could jeopardize the user's safety or
the safety of others.
ERM (Electronic Roll Mitigation)
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 will only intervene during very severe or
evasive driving maneuvers. 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:ERM is disabled anytime the ESP is in ªFull Offº
mode. Refer to ESP (Electronic Stability Program) for a
complete explanation of the available ESP modes.
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WARNING!
Many factors, such as vehicle loading, road condi-
tions, and driving conditions, influence the chance
that wheel lift or rollover may occur. ERM (Electronic
Roll Mitigation) cannot prevent all wheel lift or
rollovers, especially those that involve leaving the
roadway or striking objects or other vehicles. Only a
safe, attentive, and skillful driver can prevent acci-
dents. 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.
TSC (Trailer Sway Control) ± If Equipped
TSC uses sensors in the vehicle to recognize an exces-
sively swaying trailer. TSC activates automatically once
the excessively swaying trailer is recognized. When TSC
is functioning, the ªESP/TCS Indicatorº light will flash,
the engine power will be reduced, and you will feel the
brake being applied to individual wheels in an attempt to
stop the trailer from swaying.
NOTE:The TSC is disabled when the ESP system is in
the ªPartial Offº mode and ªFull Offº mode.
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WARNING!
²TSC (Trailer Sway Control) cannot stop all trailers
from swaying. Always use caution when towing a
trailer and follow the tongue weight recommenda-
tions. Refer to ºVehicle Loadingº and ªTrailer
Towingº in this section for more information be-
fore towing a trailer with your vehicle.
²If TSC activates while towing a trailer, stop the
vehicle at the nearest safe location and adjust the
trailer load to eliminate the trailer sway.
²Failure to follow these warnings can result in an
accident or serious personal injury.
HSA (Hill Start Assist)
The HSA system is designed to help the driver accelerate
the vehicle from a complete stop while on an incline. 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 system
will release brake pressure in proportion to amount of
throttle applied.
The following conditions must be met in order for HSA to
activate:
²The vehicle must be stopped.
²The vehicle must be on a 7% or greater incline.
²The Gear selection must match vehicle uphill direction
(i.e. vehicle facing uphill is in forward gear; vehicle
backing uphill is in reverse gear).
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²For vehicles equipped with an automatic transmission,
the HSA will work in reverse gear and all forward
gears. The system will not activate if the transmission
is in ªPº (Park).
²For vehicles equipped with a manual transmission, the
HSA will work in reverse gear, neutral, and all forward
gears.
WARNING!
There may be situations where the HSA (Hill Start
Assist) will not activate and slight rolling may occur,
such as on minor hills (i.e., less than 7%), 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 operation to ensure safe
operation of the vehicle under all road conditions.
Your complete attention is always required while
driving to maintain safe control of your vehicle.
Failure to follow these warnings can result in an
accident or serious personal injury.
Towing with HSA
HSA will provide assistance during acceleration on an
incline while towing a trailer.
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WARNING!
²If you use a trailer brake controller with your
trailer, the trailer brakes may be activated and
deactivated with the brake switch. If so, there may
not be enough brake pressure to hold both the
vehicle and the trailer on a hill when the brake
pedal is released. In order to avoid rolling down
an incline while resuming acceleration, manually
activate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake pedal.
²HSA is not a parking brake. Always apply the
parking brake fully when leaving your vehicle.
Also, be certain to leave an automatic transmission
in ªPº (Park) or a manual transmission in ªRº
(Reverse) or 1st gear.
²Failure to follow these warnings can result in an
accident or serious personal injury.
Disabling & Enabling HSA
This feature can be turned on or turned off. To change the
current setting, proceed as follows:
²For vehicles equipped with the Electronic Vehicle
Information Center (EVIC), refer to ªHill Start Assist,º
under9Personal Settings (Customer Programmable
Features),º under ªElectronic Vehicle Information
Center (EVIC)º in Section 4 of this manual.
²For vehicles not equipped with the EVIC, perform the
following steps:
NOTE:You must complete Steps 1 through 8 within 90
seconds.
1. Center the steering wheel (front wheels pointing
straight forward).
2. Shift the transmission into ªPº (Park) (automatic
transmission) or ªNº (Neutral) (manual transmission).
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3. Apply the parking brake.
4. Start the engine.
5. Release the clutch pedal (manual transmission).
6. Rotate the steering wheel
1¤2turn to the left.
7. Press the ªESP OFFº button located in the lower
switch bank below the climate control four times within
twenty seconds. The ªESP/TCS Indicatorº light should
turn on and turn off two times.
8. Rotate the steering wheel back to center and then an
additional
1¤2turn to the right.
9. Turn the ignition switch to the OFF position and then
back to the ON position. If the sequence was completed
properly, the ªESP/TCS Indicatorº light will blink sev-
eral times to confirm HSA is disabled.
10. Repeat these steps if you want to return this feature
to its previous setting.
HDC (Hill Descent Control) ± 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.
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 3 mph (4.5 km/h)
D (Drive) 7.5 mph (12 km/h)
R (Reverse) 1 mph (1.5 km/h)
N (Neutral) 3 mph (4.5 km/h)
However, the driver can override HDC operation by
applying the brake to slow the vehicle down below the
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