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2974-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
◆Adaptive Variable Suspension System (if equipped)
By independently controlling the damping force of the shock absorbers for
each of the 4 wheels according to the road and driving conditions, this system
helps riding comfort with superior steering stability, and helps good vehicle
posture (→P. 2 9 4 )
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC, hill-start
assist control, and EPS systems
Helps to maintain vehicle stability when swerving on slippery road surfaces by
controlling the brakes and hybrid system output
◆PCS (Pre-Crash Safety system) (if equipped)
→P. 3 0 2
◆Emergency brake signal
When the brakes are applied suddenly, the stop lights automatically flash to
alert the vehicle behind
◆BSM (Blind Spot Monitor) (if equipped)
→P. 3 1 0
The slip indicator light will flash while
the TRC/VSC/ABS systems are oper-
ating.
When the TRC/VSC/ABS systems are operating
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2984-5. Using the driving support systems
IS300h_EE(OM53D56E)
If the vehicle gets stuck in fresh snow or mud, the TRC system may reduce power
from the hybrid system to the wheels. Pressing to turn the system off may
make it easier for you to rock the vehicle in order to free it.
To turn the TRC system off, quickly
press and release .
The “TRC OFF” will be shown on the
multi-information display. Press
again to turn the system back on.
■Turning off both TRC and VSC systems
To turn the TRC and VSC systems off, press and hold for more than 3 seconds
while the vehicle is stopped.
The VSC OFF indicator light will come on and the “TRC OFF” will be shown on the
multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with pre-crash safety system, pre-crash brake assist and pre-crash brak- ing will also be disabled. The pre-crash safe ty system warning light will come on and
the message will be shown on the multi-information display. ( →P. 3 0 2 )
■When the message is displayed on the mult i-information display showing that TRC has
been disabled even if the VSC OFF switch has not been pressed
TRC cannot be operated. Contact any authorized Lexus dealer or repairer, or another
duly qualified and equipped professional.
Disabling the TRC system
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2994-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
■When the 12-volt battery is disconnected
The steering wheel may move from its straight forward position, but this will be corrected
automatically when driving.
■Sounds and vibrations caused by the ABS, brake assist, TRC, VSC, hill-start assist con-
trol systems
●A sound may be heard from the engine compartment when the brake pedal is
depressed repeatedly, when the hybrid system is started or just after the vehicle begins
to move. This sound does not indicate that a malfunction has occurred in any of these
systems.
●Any of the following conditions may occu r when the above systems are operating.
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.
■EPS operation sound
When the steering wheel is operated, a motor sound may be heard. This does not indi-
cate a malfunction.
■Automatic reactivation of TRC and VSC systems
After turning the TRC and VSC systems off, the systems will be automatically re-enabled
in the following situations:
●When the power switch is turned off
●If only the TRC system is turned off, the TRC will turn on when vehicle speed increases
If both the TRC and VSC systems are turned off, automatic re-enabling will not occur
when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
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 nor-
mal within 10 minutes.
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3004-5. Using the driving support systems
IS300h_EE(OM53D56E)
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.
■Operating conditions of emergency brake signal
When the following three conditions are me t, the emergency brake signal will operate:
●The emergency flashers are off.
●Actual vehicle speed is over 55 km/h (35 mph).
●The brake pedal is depressed in a manner that cause the system to judge from the vehi-
cle deceleration that this is a sudden braking operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will turn off in any of the following situations:
●The emergency flashers are turned on.
●The brake pedal is released.
●The system judges from the vehicle deceleration that is not a sudden braking operation.
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3014-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
CAUTION
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as excessively
worn tires on a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehi cle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially 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 uneven surfaces
■TRC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
●Do not overly rely on hill-start assist control. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist co ntrol is not intended to hold the vehicle
stationary for an extended period of time. Do not attempt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always dr ive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stability and driving force, do not turn the TRC/
VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the specif ied size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRC and VSC systems will not function correctly if different tires are installed
on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modi fying the suspension will affect the driving
assist systems, and may cause a system to malfunction.
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3024-5. Using the driving support systems
IS300h_EE(OM53D56E)
◆Pre-crash warning
When a high possibility of a frontal
collision is detected, the pre-crash
safety system warning light flashes, a
buzzer sounds and a message is
shown on the multi-information dis-
play to urge the driver to take eva-
sive action.
◆Pre-crash 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.
The system may not warn the driver using a warning light, warning display and
buzzer when the system detects and judges braking operations.
◆Pre-crash 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 deter-
mines that a collision is unavoidable, the brakes are automatically applied to
reduce the collision speed.
◆Suspension control (vehicles with Ad aptive Variable Suspension System)
When the system determines that there is a high possibility of a frontal colli-
sion, the operation of Adaptive Variable Suspension System ( →P. 2 9 7 ) o p t i -
mally controls the damping force of the shock absorber.
PCS (Pre-Crash Safety system)∗
∗
: If equipped
When the radar sensor detects the possibili ty of a frontal collision, brakes are
automatically engaged to lessen im pact as well as vehicle damage.
The pre-crash safety system can be turned on and off as necessary by operat-
ing the switch. ( →P. 303)
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3034-5. Using the driving support systems
4
Driving
IS300h_EE(OM53D56E)
Enabled
Disabled
The pre-crash safety system warning
light comes on when pre-crash safety
system is disabled.
The radar sensor detects vehicles or
other obstacles on or near the road
ahead and determines whether a colli-
sion is imminent based on the position,
speed, and heading of the obstacles.
Disabling pre-crash safety system
1
2
Radar sensor
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3044-5. Using the driving support systems
IS300h_EE(OM53D56E)
■The pre-crash safety system is operational when
The pre-crash safety system is enabled and the following conditions are met:
●Pre-crash warning:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle runningahead of you is greater than about 15 km/h (10 mph).
●Pre-crash brake assist:
• The VSC system is not disabled.
• Vehicle speed is greater than about 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle runningahead of you is greater than about 30 km/h (19 mph).
• The brake pedal is depressed.
●Pre-crash braking:
• The VSC system is not disabled.
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 15 km/h (10 mph).
●Suspension control (vehicles with Adap tive Variable Suspension System):
• Vehicle speed is greater than about 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle running ahead of you is greater than about 30 km/h (19 mph).
■Conditions that may trigger the system ev en if there is no danger of a collision
In any of the following situations where the frontal area of the radar sensor is interrupted,
the radar sensor may detect possibility of a frontal collision and the system may be acti-
vated.
●When passing by an oncoming vehicle in a curve or a turn to the right or the left.
●When rapidly approaching an obstacle ahead (e.g.preceding vehicle, toll gate barrier,
etc.)
●When there is a structural object (billboard , low ceiling, fluorescent light, etc.) above
the uphill road ahead
●When driving on a narrow road or through under a low overhead structure (bridge,
tunnel, fly-under, etc.)
●When driving on an uneven road surface
●When there is a metal object, bump, or protrusion on the road surface
●When vehicle’s front part is raised or lowered depending on loading conditions
●When the direction of radar sensor is misaligned by strong impact applied on an area
around the radar sensor, etc.
●When there is an obstacle (guard rail, etc.) by the roadside at the entrance to a curve
●When the front of your vehicle is pointing upwards (caused by putting a heavy load in
the trunk etc.)
When the system is activated in the situations described above, there is also a possibility
that the brakes may be applied with a force greater than normal.