2011 Lexus HS250h light

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2-4. Using other driving systems
When the VSC/TRAC systems are operatingIf the vehicle is in danger of slip-
ping or if any of the drive wheels
spins, the slip indicator light flashes
to indicate that the VSC/TRAC
systems are operating.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
Disabling the TRAC/VSC systemsIf the vehicle gets stuck in fresh snow or mud, the TRAC and VSC sys-
tems may reduce power from the hybr id system to the wheels. You may
need to turn the system off to enable you to rock the vehicle in order to
free it.
■ Turning off the TRAC system only
To turn the TRAC system off,
quickly press and release the but-
ton.
A message will be shown on the
multi-information display.
Press the button again to turn the
system back on.

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2-4. Using other driving systems
2
When driving
■Turning off both TRAC and VSC systems
To turn the TRAC and VSC sys-
tems off, press and hold the button
for more than 3 seconds while the
vehicle is stopped.
A message will be shown on the
multi-information display and
“VSC OFF” indicator will come on.
Press the button again to turn the
systems back on.
■Sounds and vibrations caused by the ABS, brake assist, VSC and TRAC
●A sound may be heard from the engine compartment when the hybrid system is
started, just after the vehicle begins to move, if the brake pedal is depressed
forcefully or repeatedly, or 1-2 minutes after the hybrid system is stopped. This
sound does not indicate that a malfunction has occurred in any of these systems.
●Any of the following conditions may occur when the above systems are operat-
ing. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Reactivation of the TRAC /VSC systems
Turning off the hybrid system after turning off the TRAC/VSC systems will automat-
ically reactivate them.
■Reactivation of the TRAC sy stem linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehi-
cle speed increases. However, when both TRAC and VSC systems are turned off,
the systems will not turn on even when vehicle speed increases.

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2-4. Using other driving systems
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from over-
heating when there is frequent steering input over an extended period of time. The
steering wheel may feel heavy as a result. Should this occur, refrain from excessive
steering input or stop the vehicle and turn the hybrid system off. The EPS system
should return to normal within 10 minutes.
CAUTION
■The ABS does not operate effectively when
●Tires with inadequate gripping ability ar e used (such as excessively worn tires on
a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick road.
■Stopping distance when the ABS is operating will exceed that of normal condi-
tions
The ABS is not designed to shorten the vehicle’s stopping dist ance. Always main-
tain a safe distance from the vehicle in front of you in the following situations:
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or roads with uneven surfaces
■TRAC may not operate effectively when
Directional control and power may not be ac hievable while driving on slippery road
surfaces, even if the TRAC system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
■When the VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive carefully.
Reckless driving may cause an accident. Exercise particular care when the indica-
tor light flashes and a buzzer sounds.
■When the TRAC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As
these are the systems to ensure vehicle stability and driving force, do not turn the
TRAC/VSC systems off unless necessary.

234
2-4. Using other driving systems
Hill-start assist control
■Hill-start assist control can be operated when
●The shift position is in a position other than P.
●The parking brake is not applied.
●The accelerator pedal is not depressed.
■Hill-start assist control
●While hill-start assist control is operating, the brakes remain automatically
applied after the driver releases the br ake pedal. The stop lights and the high
mounted stoplight turn on.
●Hill-start assist control operates for about 2 seconds after the brake pedal is
released.
●If the slip indicator does not flash and the buzzer does not sound when the brake
pedal is further depressed, slightly redu ce the pressure on the brake pedal (do
not allow the vehicle to roll backward) and then firmly depress it again. If the sys-
tem still does not operate, check if th e operating conditions explained above
have been met.
Hill-start assist control helps to prevent the vehicle from rolling backwards
when starting on an incline or slippery slope.
To engage hill-start assist con-
trol, further depress the brake
pedal when the vehicle is
stopped completely.
A buzzer will sound once to
indicate the system is activated.
The slip indicator will also start
flashing.

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2-4. Using other driving systems
Pre-Collision System
: If equipped
When the radar sensor detects possibilit y of a frontal collision, the pre-col-
lision system such as the brakes and seat belts are automatically engaged
to lessen impact and injuries to occupants as well as vehicle damage.
■Pre-collision seat belts (front seat belts only)
If the pre-collision sensor detects that a collision is unavoidable, the pre-
collision system will retract the seat belt before the collision occurs.
The same will happen if the driver makes an emergency braking or loses
control of the vehicle. ( P. 7 5 )
However, when the VSC system is disabled, the system will not operate in
the event of skidding.
■ Pre-collision brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed.
■Pre-collision braking
When there is a high possibility of a frontal collision, the system warns the
driver using a warning light, warning display* and buzzer. If the system
determines that a collision is unavoidable, the brakes are automatically
applied to reduce the collision speed. Pre-collision braking can be dis-
abled using the pre-collision braking off switch.
*: When the pre-collision braking system activates, “BRAKE!” will appear on the multi-information display and head-up display (if equipped), and
the warning light will begin flashing rapidly. ( P. 5 1 4 )
■Driver monitor system (if equipped)
When the system determines that there is a possibility of a frontal collision,
and the driver is not facing forward, PCS warnings are given in advance to
warn the driver. If the driver continue s to be not facing forward, and a high
possibility of a frontal collision is dete cted, PCS informs the driver of high
possibility of a frontal collision by perf orming slight braking to provide a
physically warning (pre-collision alert braking). ( P. 2 3 8 )

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2-4. Using other driving systems
2
When driving
Disabling pre-collision brakingPre-collision braking disabled
Pre-collision braking enabled
The “PCS” warning light will
turn on when pre-collision brak-
ing is disabled.
Radar sensorThe radar sensor detects vehicles
or other obstacles on or near the
road ahead and determines
whether a collision is imminent
based on the position, speed, and
heading of the obstacles.
For vehicles equipped with the lane
keeping assist, in addition to the
radar sensor, the vehicle uses a
lane recognition camera in order
to determine whether or not a colli-
sion is likely to occur. ( P. 2 2 8 )

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2-4. Using other driving systems
■Automatic cancellation of the pre-collision system
When a malfunction occurs due to sensor contamination, etc. that results in the
sensors being unable to detect obstacles, the pre-collision system will be automati-
cally disabled. In this case, the system will not activate even if there is a collision pos-
sibility.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may also be
occasions when the sensor cannot detect pedestrians, animals, bicycles, motorcy-
cles, trees, or snowdrifts.
■If the PCS warning light turns on or flashes
●If the PCS warning light begins flash ing and “CHECK PCS SYSTEM” appears
on the multi-information display, this in dicates a malfunction in the pre-collision
system. ( P. 5 0 8 )
●If the PCS warning light turns on and “PCS TEMPORARILY NOT
AVAILABLE” appears on the multi-information display, this indicates that the
grille or radar sensor is dirty. ( P. 5 1 3 )

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2-4. Using other driving systems
2
When driving
CAUTION
■When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary in any of the following situations.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by a heavy load in the luggage
compartment etc.)
●Vehicles that cut in suddenly
●Vehicles with small rear ends (tra ilers with no load on board etc.)
●Motorcycles traveling in the same lane
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively:
●Keep the sensor and front grille cover clean at all times.
Clean the sensor and front grille cover with a soft cloth so you do not mark or
damage them.
●Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off po sition, the system may become inaccurate
or malfunction. If the sensor or surround ing area is subject to a strong impact,
always have the area inspected an d adjusted by your Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
■Determining the direction the driver is fa cing (vehicles with driver monitor sen-
sor)
The direction the driver is facing may not be determined correctly if the following
conditions exist:
●There is an object between the driver mo nitor sensor and the driver’s face, such
as when the sensor is blocked.
●A part of the driver’s face is covered.
●The sensor or the driver’s face is exposed to intense light such as sunlight.
●The driving posture is improper.