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2-3. Operating the lights and windshield wipers
10_IS250C/350C_U
■Rain drop sensor (vehicles with the rain-sensing windshield wipers)
■Outside rear view mirror defogger activation linked to windshield wiper opera-
tion
The outside rear view mirror defogger automatically turns on when you operate the
windshield wipers.
■If no windshield washer fluid sprays
Check that the washer nozzles are not blocked if there is washer fluid in the wind-
shield washer fluid reservoir.
■Customization that can be configured at Lexus dealer
Settings (e.g. drip prevention function) can be changed.
(Customizable features →P. 5 5 7 )
CAUTION
■Caution regarding the use of windshield wipers in “AUTO” mode
The windshield wipers may operate unexpectedly if the sensor is touched or the
windshield is subject to vibration in “AUTO” mode. Take care that your fingers or
anything else do not become caught in the windshield wipers.
The sensor judges the amount of raindrops.
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When driving
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NOTICE
■When the windshield is dry
Do not use the wipers, as they may damage the windshield.
■When a nozzle becomes blocked
Do not try to clear it with a pin or other object. The nozzle will be damaged.
■When there is no washer fluid spray from the nozzle
Damage to the washer fluid pump may be caused if the lever is pulled toward you
and held continually.
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2-3. Operating the lights and windshield wipers
10_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. 177)
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
10_IS250C/350C_U
■Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is obtained.
Fine adjustment of the set
speed (approximately 1.0 mph
[1.6 km/h]) can be made by
lightly pressing the lever up or
down and releasing it.
■Canceling and resuming regular acceleration
Cancel
Push the lever towards you to
cancel cruise control.
The speed setting is also can-
celed when the brakes are
applied or the clutch (manual
transmission) is depressed.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
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When driving
10_IS250C/350C_U
■Cruise control can be set when
●Vehicles with an automatic transmission: the shift lever is in the D position or S
position. However, it cannot be set if any of the ranges 1 through 3 has been
selected.
●Vehicle speed is more than approximately 25 mph (40 km/h).
■Accelerating
The vehicle can be accelerated normally. After acceleration, the set speed
resumes.
■Automatic cruise control cancellation
The set speed is automatically cancelled in any of the following situations.
●Actual vehicle speed falls more than 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 25 mph (40km/h)
●VSC is activated
■If the cruise control indicator light flashes
Turn the “ON-OFF” button off once, and then 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
10_IS250C/350C_U
■Driving in the selected cruise control mode
Accelerate or decelerate to the
desired speed and press the
lever down to set.
■ Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is displayed.
Fine adjustment of the set speed
can be made by lightly pressing
the lever up or down and releas-
ing it. Adjustment can be made
in increments of approximately
1.0 mph (1.6 km/h) when in the
constant speed control mode,
and approximately 5.0 mph or
5.0 km/h when in the vehicle-
to-vehicle distance control
mode.
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10_IS250C/350C_U
The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration (when there are no longer vehicles driving
slower than the set speed in the lane ahead): When the speed is set to
62 mph (100 km/h) and the vehicle ahead driving at 50 mph (80
km/h) is out of the lane
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
■Dynamic radar cruise control warning lights, messages and buzzers
Warning lights, messages and buzzers are used to indicate a system malfunction or
to alert you to the need for caution while driving. ( →P. 4 7 2 )
■The dynamic radar cruise can be set when
●The shift lever is in the D position or S position. However, it cannot be set if any
of the ranges 1 through 3 has been selected.
●Vehicle speed is more than approximately 30 mph (50 km/h).
■Accelerating
The vehicle can be accelerated normally.
■Automatically canceling vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the follow-
ing situations.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated
●The sensor cannot operate correctly because it is covered in some way.
●The windshield wipers are operating at high speed.
●The “ECT SNOW” switch is set to snow mode.
If vehicle-to-vehicle distance control driving is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.
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When driving
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CAUTION
■Handling the radar sensor
Observe the following to ensure the cruise control 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 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 or surrounding area.
●Do not modify or paint the sensor and grille.
■To ensure the radar sensor functions correctly
Do not do the following to the sensor or grille cover as doing so may cause the sen-
sor not to function correctly and could result in an accident.
●Stick or attach anything to them
●Leave them dirty
●Disassemble, subject them to strong shocks
●Modify or paint them
●Replace them with non-genuine parts