2007 Lexus IS250 engine

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2-4. Using other driving systems
■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 4 4
■Certification (Canada only)
This ISM device compiles with Canadian ICES-001.
■Customization
Settings (e.g. buzzer volume) can be changed. (P. 406)

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2-4. Using other driving systems
2
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
(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, 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 5 4

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2-4. Using other driving systems
To disable TRAC /VSC
When the TRC/VSC systems are operating, depressing the accelerator
pedal may not increase the engine output and the vehicle may get stuck
in fresh snow or mud. Turning the TRC/VSC systems off may help the
vehicle get out.
■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/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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2-4. Using other driving systems
2
When driving
■Automatic TRAC reactivation
If only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases.
■Automatic TRAC/VSC reactivation
If the TRAC/VSC systems are turned off, the systems will not turn on even when
vehicle speed increases.
■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.

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2-4. Using other driving systems
■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
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 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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2-5. Driving information
2
When driving
Winter driving tips
Carry out the necessary preparations and inspections before driving the
vehicle in winter. Always drive the vehicle in a manner appropriate to the
prevailing weather conditions.
■Pre-winter preparations
●Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine coolant
• Washer fluid
• Have a service technician inspect the level and specific gravity
of battery electrolyte.
●Have the vehicle fitted with four snow tires or purchase a set of
tire chains for the rear tires.
Ensure that all tires are the specified size and the same brand, and that
chains match the size of the tires.
■Before driving the vehicle
Perform the following according to the driving conditions.
●Do not try to forcibly open a window or move a wiper that is fro-
zen. Pour warm water over the frozen area to melt the ice. Wipe
away the water immediately to prevent it from freezing.
●To ensure proper operation of the climate control system fan,
remove any snow that has accumulated on the air inlet vents in
front of the windshield.
●Remove any ice that has accumulated on the vehicle chassis.
●Periodically check for and remove any excess ice or snow that
may have accumulated in the wheel well or on the brakes.

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2-5. Driving information
2
When driving
Dinghy towing (vehicles with a manual transmission)
Towing your vehicle with 4 wheels on the ground
To prevent damage to your vehicle, perform the following procedures
before towing.
Shift the shift lever to neutral.
Switch to ACC mode. (P. 9 8 )
Ensure that the audio system and other powered devices have been
turned OFF.
Release the parking brake.
After towing, leave the engine in idle for at least 3 minutes before driv-
ing the vehicle.
■Necessary equipment and accessories
Specialized equipment and accessories are required for dinghy towing. Contact
the service branch of the motor home manufacturer regarding recommended
equipment.
Your vehicle can be dinghy towed in a forward direction (with 4 wheels on
the ground) behind a motor home.
STEP1
STEP2
STEP3

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2-5. Driving information
NOTICE
■Dinghy towing direction
■To prevent the steering from locking
Ensure the engine switch is in ACC mode.
Do not tow the vehicle backwards.
Doing so may cause serious damage.