Lexus IS250 2006 Other Functions / LEXUS 2006 IS350/250 FROM MAY 2006 PROD. OWNER'S MANUAL (OM53619U)

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2-4. Using other driving systems
2
When driving
CAUTION
■Caution when using the Lexus parking-assist 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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2-4. Using other driving systems
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.
■BA (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 th e rear wheels (2WD models) or all
wheels (4WD models) from spinning when starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Prevents the vehicle from rolling backwa rds 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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2-4. Using other driving systems
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When drivingWhen the VSC/TRAC/hill-start assist control systems are operating
If the vehicle is in danger of slip-
ping, rolling backwards when
starting on an incline, or if the rear
wheels (2WD) or 4 wheels
(4WD) 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, BA, 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 4 9

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2-4. Using other driving systems
To disable TRAC (2WD vehicles only) If the vehicle gets stuck in fresh sn ow or mud, TRAC 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 the vehicle.
Push the button to turn off
TRAC.
The slip indicator light should come
on.
Push the button again to turn the
system back on.
■Automatic TRAC reactivation (IS 350)
The TRAC system is reactivated when vehicle speed exceeds 30 mph (50 km/h)
even if TRAC OFF has been turned off.
■Sounds and vibrations caused by the ABS, BA, 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.
■Hill-start assist control is operational when
●The shift lever is in the D or S position.
●The brake pedal is not depressed.

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2-4. Using other driving systems
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When driving
■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
Any of the following conditions may result in an accident which could cause death or
serious injury:
■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 ve hicle’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
■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.
■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.

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2-4. Using other driving systems
CAUTION
■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 info rmation 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.

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2-4. Using other driving systems
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When driving
PCS (Pre-Collision System) (if equipped)
Radar sensorDetects vehicles or other obsta-
cles on or near the road ahead and
determines whether a collision is
imminent based on the position,
speed, and heading of the obsta-
cles. Grille cover
Radar sensor
Safety systems such as the brakes and seat belts are automatically
engaged to lessen impact and injuries to occupants as well as vehicle dam-
age when the radar sensor detects an unavoidable frontal collision.
■Pre-collision seat belts
The seat belts are immediately retracted as the effect of the pretensioner is
increased ( P. 35), to provide even greater constraining force to protect
the driver and passengers. In the event of sudden braking or skidding, the
system will operate even if no obstacle has been detected.
■Pre-collision brake assist
Applies greater braking force in relati on to how strongly the brake pedal is
depressed.
■Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be occa-
sions when the sensor cannot detect pedestrians, animals, bicycles, motorcycles,
trees, or snowdrifts.

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2-4. Using other driving systems
■The pre-collision system is operational when
●Seat belt (linked to the radar sensor)
• Vehicle speed is above 3 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or oncomingvehicle exceeds 18 to 24 mph (30 to 40 km/h).
• The front occupants are wearing a seat belt.
●Seat belts (linked to brake operation)
• Vehicle speed exceeds 9 mph (15 km/h).
• The system detects sudd en braking or skidding.
• The front occupants are wearing a seat belt.
●Brake Assist
• Vehicle speed is above 18 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehicle is greater than 18 to 24 mph (30 to 40 km/h).
• The brake pedal is depressed.
■Conditions that may trigger the system even if there is no danger of collision
●When there is an object by the roadside at the entrance to a curve
●When passing an oncoming vehicle on a curve
●When driving over a narrow iron bridge
●When there is a metal object on the road surface
●When driving on an uneven road surface
●When passing an oncoming vehicle on a left-turn
●When your vehicle rapidly closes on the vehicle in front
When the system is activated in the situations described above there is also a possi-
bility that the seat belts will retract quickly and the brakes will be applied with a force
greater than normal. When the seat belt is locked in the retracted position, stop the
vehicle in a safe place, release the seat belt and refasten.
■When there is a malfunction in the system
Warning lights and/or warning messages will turn on or flash. ( P. 333, P. 338)

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2-4. Using other driving systems
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When driving
CAUTION
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
●Keep the sensor and front grille clean at all times.
Clean the sensor and front grille 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 position, the system may malfunction. If the
sensor or surrounding area are subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille guard or surrounding
area.
■Limitations of the pre-collision system
Do not rely on the pre-collision system. Always drive safely, taking care to observe
your surroundings and checking for any obstacles or other road hazards.

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2-5. Driving information
Cargo and luggage
Capacity and distributionCargo capacity depends on the to tal weight of the occupants.
(Cargo capacity) = (Total load capa city) — (Total weight of occupants)
Steps for Determining Correct Load Limit 
(1) Locate the statement “The combined weight of occupants and cargo should never exceed XXX kg or XXX lbs.” on your vehicle’s placard.
(2) Determine the combined weight of th e driver and passengers that will
be riding in your vehicle.
(3)Subtract the combined weight of the driver and passengers from
XXX kg or XXX lbs.
(4)The resulting figure equals the av ailable amount of cargo and luggage
load capacity.
For example, if the “XXX” amount equals 1400 lbs. and there will be
five 150 lb passengers in your vehicle, the amount of available cargo
and luggage load capacity is 650 lbs. (1400  750 (5150) = 650
lbs.)
(5)Determine the combined weight of luggage and cargo being loaded
on the vehicle. That weight may no t safely exceed the available cargo
and luggage load capacity calculated in Step 4.
Take notice of the following information about storage precautions, cargo
capacity and load.
● Stow cargo and luggage in the tru nk whenever possible. Be sure
all items are secured in place.
● Be careful to keep the vehicle level. Placing the weight as far for-
ward as possible helps maintain vehicle balance.
● For better fuel economy, do not carry unnecessary weight.