light Lexus HS250h 2012 Manual Online

208
2-3. Operating the lights and windshield wipers
HS250h_U_75050U
Type BRain-sensing wiper
operation
Low speed wiper
operation
High speed wiper
operation
Temporary operation
Increases the sensitivity
Decreases the sensitivity

209
2-3. Operating the lights and windshield wipers
2
When driving
HS250h_U_75050U
■The windshield wipers and washer can be operated when
The “POWER” switch is in ON mode.
■Effects of vehicle speed on wiper operation (vehicles with rain-sensing wind-
shield wipers)
Even when the wipers are not in AUTO mode, wiper operation varies depending
on vehicle speed when the washer is being used (delay until drip prevention wiper
sweep occurs).
■Raindrop sensor (vehicles with rain-sensing windshield wipers)
●If the wiper switch is turned to the position while the “POWER” switch is
in ON mode, the wipers will operate once to show that AUTO mode is acti-
vated.
●If the temperature of the raindrop sensor is 194 °F (90 °C) or higher, or 14 °F
(-10 °C) or lower, automatic operation may not occur. In this case, operate the
wipers in any mode other than “AUTO”.
Washer/wiper dual operation
The wipers will automatically
operate a couple of times after
the washer squirts.
(After operating several times,
the wipers operate one more
time after a short delay to pre-
vent dripping.)
If the headlights are on, the
headlight cleaners will operate
once. ( →P. 211)
●The raindrop sensor judges the amount of
raindrops.
An optical sensor is adopted. It may not
operate properly when sunlight from the
rising or setting of the sun intermittently
strikes the windshield, or if bugs etc. are
present on the windshield.

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2-3. Operating the lights and windshield wipers
HS250h_U_75050U
■If no windshield washer fluid sprays
Check that the washer nozzles are not blocked if there is washer fluid in the washer
fluid tank.
CAUTION
■Caution regarding the use of windshield wipers in AUTO mode (vehicles with
rain-sensing windshield wipers)
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 etc. do
not become caught in the windshield wipers.
NOTICE
■When the windshield is dry
Do not use the wipers, as they may damage the windshield.
■When the washer fluid tank is empty
Do not operate the switch continually as the washer fluid pump may overheat.
■When a nozzle becomes blocked
Do not try to clear it with a pin or other object. The nozzle will be damaged.
■To prevent 12-volt battery discharge
Do not leave the wipers on longer than necessary when the hybrid system is off.

211
2-3. Operating the lights and windshield wipers
2
When driving
HS250h_U_75050U
Headlight cleaner switch∗
∗: If equipped
■The headlight cleaners can be operated when
The “POWER” switch is in ON mode and the headlight switch is turned on.
■Windshield washer linked operation
●When the windshield washer is operated with the “POWER” switch in ON
mode and the headlights on, the headlight cleaners will operate once.
(→ P. 2 0 4 )
●From the second time the windshield washer is operated, the headlight cleaner
will not operate in sync with the windshield washer.
(Turning the “POWER” switch to OFF or the low beam headlights off resets the
headlight cleaner synchronization mode.)
NOTICE
■When the washer fluid tank is empty
Do not press the switch continually as the washer fluid pump may overheat.
Washer fluid can be sprayed on the headlights.
Press the switch to clean the
headlights.

215
2-4. Using other driving systems
2
When driving
HS250h_U_75050U
■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.
CAUTION
■To avoid operating the cruise control by mistake
Switch the cruise control off using the “ON-OFF” button when not in use.
■Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in loss of control and could cause an accident resulting in death
or serious injury.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those covered with rain, ice or snow
●On steep hills
Vehicle speed may exceed the set speed when driving down a steep hill.

225
2-4. Using other driving systems
2
When driving
HS250h_U_75050U
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situations:
●Actual vehicle speed is more than approximately 10 mph (16 km/h) below the
set vehicle speed.
At this time, the memorized set speed is not retained.
●Vehicle speed falls below approximately 25 mph (40 km/h).
●Enhanced VSC is activated.
■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 and plas-
tic 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. 503, 513, 516)
Grille cover
Radar sensor

229
2-4. Using other driving systems
2
When driving
HS250h_U_75050U
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.

230
2-4. Using other driving systems
HS250h_U_75050U
LKA (Lane-Keeping Assist)∗∗
: If equipped
While driving on a freeway or motor highway that has lane markers, this
system recognizes the lanes using a camera as a sensor to assist the driver
with staying in the lane. The LKA system has two functions.
■Lane departure warning function
If the system judges that the vehicle may deviate from its lane, it
alerts the driver using rapid beeping, indications on the multi-infor-
mation display, and a sensory warning
* given via the steering wheel.
*: A slight steering torque is applied for a short period of time in the
direction of the center of the lane.
■ Lane keeping assist function
This function will be active when the vehicle-to-vehicle distance
control mode of the cruise control ( →P. 216) is set with vehicle
speed above approx. 45 mph (approx. 72 km/h) and while the lane
departure warning function is active. When the lane keeping assist
function is active, a slight steering torque will be applied, to help the
driver maintain the vehicle inside the lane.

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2-4. Using other driving systems
HS250h_U_75050U
●When the lane lines cannot be recognized while driving.
●The wiper operates continuously.
●When the lane departure warning function is activated.
The lane departure warning function will be temporarily canceled and will not
resume until a few seconds elapse after it is activated.
■No-handed driving warning
If the steering wheel is not operated for about 15 seconds on a straight road or
about 5 seconds on a curve, the buzzer will beep twice, indicators on the multi-
information display will flash, and the lane keeping assist function will be temporarily
canceled. If you drive the vehicle with your hands lightly touching the steering
wheel, this may also be detected as no-handed driving.
■When the vehicle has been parked in the sun
The LKA system functions may not be available for a while after driving has started.
In such cases, turn the LKA system off and turn it on again after normal temperature
returns. When the temperature in the cabin decreases and the temperature around
the camera sensor becomes suitable for its operation, the functions will begin to
operate.
■Warning lights and messages for LKA
Warning lights and messages are used to indicate a system malfunction or to inform
the driver of the need for caution while driving. (→P. 5 0 3 , 5 1 6 )

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2-4. Using other driving systems
HS250h_U_75050U
NOTICE
■In the following situations, the LKA will not work, or will not perform reliably:
●When lane markers are interrupted or are not present, such as before a tollbooth.
●When lane markers are only on one side of the road.
●When driving on a sharp curve.
●When lanes are extremely narrow or extremely wide.
●When the vehicle leans to one side an unusual amount due to a heavy load or
improper tire inflation pressure.
●When the following distance between your vehicle and the vehicle ahead is
extremely short.
●When the lane markers are broken, “Botts’ dots”, or “Raised pavement marker”.
●When lane markers are obscured or partially obscured by sand, dirt, etc.
●When driving on a particularly bright road surface, such as concrete.
●When driving on a road surface that is bright due to reflected light.
●When driving in a location where the light level changes rapidly, such as the
entrance to or exit from a tunnel.
●When sunlight or the headlights of oncoming vehicles are shining directly into the
camera lens.
●When driving on roads that are branching or merging.
●When pavement lane markers are difficult to see due to rain, snow, fog, etc.
●When driving on a road surface that is wet due to rain, previous rainfall, standing
water, etc.
●When the vehicle experiences strong up-and-down motion such as when driving
on an extremely rough road or on a seam in the pavement.
●When headlight brightness is reduced due to dirt on the lenses, or when the
headlights are misaligned.
●When driving with a strong crosswind.