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CAUTION
Conditions under which the vehicle-to-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
When water or snow thrown up by the surrounding vehicles hinders the
functioning of the sensor
When your vehicle is pointing upwards (caused by a heavy load in the
trunk etc.)
When the road curves or when the lanes are narrow
When steering wheel operation or your position in the lane is unstable
When the vehicle ahead of you decelerates suddenly
Handling the radar sensor
Observe the following to ensure the cruise control system can function
effectively.
Otherwise, the system may not function correctly and could result in an
accident.
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 position, the system may malfunc-
tion. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Do not disassemble the sensor.
Do not attach accessories or stickers to the sensor, grille cover or sur-
rounding area.
Do not modify or paint the sensor and grille cover.
Do not replace them with non-genuine parts.
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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
particular 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
If the display flashes and a message is displayed
P. 4 7 3
Customization that can be configured at any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
Settings (e.g. buzzer volume) can be changed. (Customizable features P.
556)
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IS250/220d/200d_EETurning off TRC and VSC
Push and hold the switch for
more than 3 seconds or more
while the vehicle is stopped to
turn off TRC and VSC.
A message will be shown on the
multi- information display and
the VSC off indicator light will
come on.
Push the switch again to turn
the system back on.
When the message is displayed on the multi-information display showing
that TRC has been disabled even if the VSC off switch has not been pressed
(IS250 only)
TRC and hill-start assist control cannot be operated. Contact any authorized
Lexus dealer or repairer, or another duly qualified and equipped profes-
sional.
Automatic reactivation of the TRC/VSC systems
If the TRC/VSC systems are turned off, re-starting the engine will automati-
cally reactivate them.
Automatic TRC reactivation
If only the TRC system is turned off, the TRC system will turn on when
vehicle speed increases.
Automatic TRC and VSC reactivation
If the TRC and VSC systems are turned off, the systems will not turn on
even when vehicle speed increases.
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2
When driving
IS250/220d/200d_EE
Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and hill-
start assist control systems
A sound may be heard from the engine compartment if the brake pedal is
depressed repeatedly 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
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.
• The brake pedal may pulsate slightly when 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.
The vehicle rolls backward.
EPS operation sound
When the steering wheel operates, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
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.
If the slip indicator comes on
It may indicate a malfunction in the VSC, TRC or hill start assist control
function. Contact any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.
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2
When driving
IS250/220d/200d_EE
CAUTION
Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and
total load capacity. In addition, make sure that the tires are inflated to the
appropriate tire pressure level.
The ABS, VSC and TRC systems will not function correctly if different
tires are fitted 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 suspension
Using tires with any kind of problem or modifying the suspension will
affect the driving assist systems, and may cause the system to malfunction.
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CAUTION
Handling the radar sensor
Observe the following to ensure the pre-crash safety 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 become
inaccurate or malfunction. If the sensor or surrounding area are subject to
a strong impact, always have the area inspected and adjusted by any
authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Do not disassemble the sensor.
Do not attach accessories or stickers to the sensor, grille guard or sur-
rounding area.
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2-5. Driving information
2
When driving
IS250/220d/200d_EE
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
temperatures.
• 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 frozen. 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 chas-
sis.
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2-5. Driving information
2
When driving
IS250/220d/200d_EERetighten the chains after driving 0.5 1.0 km (1/4 1/2
mile).
Tire chains (models with 16- and 17-inch tires)
Observe the following precautions when installing and removing chains.
Install and remove tire chains in a safe location.
Install tire chains on the rear tires. Do not install tire chains on front tires.
Install tire chains following the instructions provided in the accompany-
ing manual.
CAUTION
Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or
serious injury.
Use tires of the specified size.
Maintain the recommended level of air pressure.
Do not drive at speeds in excess of the speed limit or the speed limit spec-
ified for the snow tires being used.
Driving with tire chains (models with 16- and 17-inch tires)
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely,
and may cause death or serious injury.
Do not drive in excess of the speed limit specified for the tire chains being
used or 50 km/h (30 mph), whichever is lower.
Avoid driving on bumpy road surfaces or over potholes.
Avoid sudden turns and braking.
Slow down sufficiently before entering a curve to ensure that vehicle con-
trol is maintained.