2008 Lexus IS250 Owner's Manual

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■Sensor detection information
●Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where this
may occur are listed below.
• There is dirt, snow or ice on the sensor.
• The sensor is frozen.
•The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle engines,air brakes of large vehicles, or other loud noises producing ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather
In addition to the examples above, there are instances in which, because of their
shapes, signs and other objects may be judged by the sensor to be closer than they
are.
●The shape of the obstacle may prevent the sensor from detecting it. Pay particu-
lar attention to the following obstacles.
• Wires, fences, ropes etc.
• Cotton, snow and other materials that absorb radio waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your
vehicle
■When the display flashes and a message is displayed
→P. 3 6 9
■Certification (Canada only)
This ISM device compiles with Canadian ICES-001.

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■Customization that can be configured at Lexus dealer
Settings (e.g. buzzer volume) can be changed. (Customizable features →P. 4 3 6 )
CAUTION
■Caution when using the intuitive parking sensor
Observe the following precautions.
Failing to do so may result in the vehicle being unable to be driven safely and possi-
bly cause an accident.
●Do not use the sensor at speeds in excess of 6 mph (10 km/h).
●Do not attach any accessories within the sensor range.
NOTICE
■Notes when washing the vehicle
Do not apply intensive bursts of water or steam to the sensor area.
Doing so may result in the sensor malfunctioning.

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Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Restrains the vehicle from slipping when driving on slick road surfaces or
in the event of sudden braking.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Maintains drive power and prevents the rear wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Prevents the vehicle from rolling backwards when starting on an incline or
slippery slope.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.

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When the VSC/TRAC/hill-start assist control systems are operatingIf the vehicle is in danger of slip-
ping, rolling backwards when
starting on an incline, or if the rear
wheels (2WD) or 4 wheels
(AWD) spin, the slip indicator light
flashes to indicate that the VSC/
TRAC/hill-start assist control sys-
tems have been engaged.
A buzzer (intermittent) sounds to
indicate that VSC is operating.
The stop lights and high mounted
stoplight turn on when the hill-start
assist control system is operating.
■VDIM (Vehicle Dynamics Integrated Management) (IS350)
Provides integrated control of the ABS, brake assist, TRAC, VSC, hill-start
assist control, and EPS systems.
Maintains vehicle stability when swerving on slippery road surfaces by
controlling the brakes and engine output.
■PCS (Pre-Collision System) (if equipped)
→P. 1 76

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To disable TRAC and/or VSCIf the vehicle gets stuck in fresh snow or mud, TRAC and VSC may
reduce power from the engine 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 TRAC
Quickly push and release the but-
ton to turn off TRAC.
The slip indicator light should come
on.
Push the button again to turn the
system back on.
■Turning off TRAC and VSC
Push and hold the button for more
than 3 seconds while the vehicle is
stopped to turn off TRAC and
VSC.
The slip indicator light and “VSC
OFF” indicator light should come
on.
Push the button again to turn the
system back on.

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■Automatic reactivation of TRAC and VSC
Turning the “ENGINE START STOP” switch OFF after turning off the TRAC and
VSC systems will automatically re-enable them.
■Automatic TRAC reactivation
If only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases.
■Automatic TRAC and VSC reactivation
If the TRAC and VSC systems are turned off, the systems will not turn on even when
vehicle speed increases.
■Sounds and vibrations caused by the ABS, brake assist, VSC, TRAC and hill-start
assist control systems
●A sound may be heard from the engine compartment when the engine 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 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.

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■Hill-start assist control is operational when
●The shift lever is in the D or S position.
●The brake pedal is not depressed.
■Reduced effectiveness of EPS
The effectiveness of EPS 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 engine OFF. The system should return to normal within
10 minutes.
CAUTION
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded.
●The vehicle hydroplanes while driving at high speed on the 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 distance. 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 roads

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CAUTION
■TRAC may not operate effectively when
Directional control and power may not be achievable 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.
■If hill-start assist control does not operate effectively
(vehicles with an automatic transmission)
The hill-start assist control may not operate effectively on steep inclines and roads
covered in ice.
■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 TRAC and VSC are off
Be especially careful and drive at a speed appropriate to the road conditions. As
there are systems to ensure vehicle stability and driving force, do not turn off TRAC
and VSC unless necessary.
■Replacing tires
Make sure that all tires are of the same size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire
pressure level.
The ABS and VSC systems will not function correctly if different tires are fitted on
the vehicle.
Contact your Lexus dealer for further information when replacing tires or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will affect the driv-
ing assist systems, and may cause the system to malfunction.