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2-3. Operating the lights and windshield wipers
2
When driving
IS250C/350C_U
Headlight cleaner switch∗
■The headlight cleaner can be operated when
When the “ENGINE START STOP” switch is in IGNITION ON mode and the
headlight switch is turned on.
■Windshield washer linked operation
Only for the first time when the windshield washer is operated after the “ENGINE
START STOP” switch is turned to IGNITION ON mode with the headlights on, the
headlight cleaners will also operate once. ( →P. 1 8 2 )
NOTICE
■When the washer fluid tank is empty
Do not use this function when the washer fluid tank is empty. This may cause the
washer fluid pump to overheat.
Washer fluid can be sprayed on the headlights.
Press the switch to clean the
headlights.
∗: If equipped
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2-4. Using other driving systems
IS250C/350C_U
■Cruise control can be set when
●The shift lever is in the D or range 4 or higher of S has been selected.
●Range 4 or higher has been selected by using the paddle shift.
●Vehicle speed is above approximately 25 mph (40 km/h).
■Accelerating after setting the vehicle speed
●The vehicle can be accelerated normally. After acceleration, the set speed
resumes.
●Even without canceling the cruise control, the set speed can be increased by
first accelerating the vehicle to the desired speed and then pushing the lever
down to set the new speed.
■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicle speed in any of the following situa-
tions.
●Actual vehicle speed falls more than approximately 10 mph (16 km/h) below the
preset vehicle speed.
At this time, the memorized set speed is not retained.
●Actual vehicle speed is below approximately 25 mph (40 km/h).
●VSC is activated.
■If the cruise control indicator light flashes
Press the “ON-OFF” button once to deactivate the system, and then press the but-
ton again to reactivate the system.
If the cruise control speed cannot be set or if the cruise control cancels immediately
after being activated, there may be a malfunction in the cruise control system. Have
the vehicle inspected by your Lexus dealer.
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2-4. Using other driving systems
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When driving
IS250C/350C_U
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle
distance control operates properly. (Some obstructions, such as snow, ice or plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled if an obstruction is detected.
■Warning lights, messages and buzzers for dynamic radar cruise control
Warning lights, messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. (→P. 500)
Grille cover
Radar sensor
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2-4. Using other driving systems
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When driving
IS250C/350C_U
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 sensor 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 function-
ing 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 grille cover clean at all times.
Clean the sensor and 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 malfunction. If the
sensor or surrounding area is 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 cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.
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2-4. Using other driving systems
IS250C/350C_U
■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. 5 0 0
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2-4. Using other driving systems
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When driving
IS250C/350C_U
When the VSC/TRAC systems are operatingThe slip indicator light flashes to
indicate that the VSC/TRAC sys-
tems have been engaged.
■VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC, and
EPS systems.
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, engine output and steering assist.
■PCS (Pre-Collision System) (if equipped)
→ P. 222
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2-4. Using other driving systems
IS250C/350C_U
To disable TRAC/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
switch to turn off TRAC.
A message will be shown on the
multi-information display.
Push the switch again to turn the
system back on.
■Turning off TRAC and VSC
To turn the TRAC and VSC sys-
tems off, press and hold the switch
for 3 seconds or more while the
vehicle is stopped.
A message will be shown on the
multi-information display and VSC
off indicator light will come on.
Push the switch again to turn the
system back on.
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2-4. Using other driving systems
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When driving
IS250C/350C_U
■When the message is displayed on the multi-information display showing that
TRAC has been disabled even if the VSC off switch has not been pressed
TRAC and hill-start assist control cannot be operated. Contact your Lexus dealer.
■Automatic reactivation of the TRAC/VSC systems
If the TRAC/VSC systems are turned off, re-starting the engine will automatically
reactivate 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 and TRAC 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 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.