stop start Lexus IS250 2010 Service Manual

171
2-3. Operating the lights and windshield wipers
2
When driving
IS350/250_U
■The windshield wipers and washer can be operated when
The “ENGINE START STOP” switch is in IGNITION ON mode.
■Effects of vehicle speed on wiper operation
Vehicle speed affects the following even when the wipers are not in “AUTO” mode.
●Intermittent wiper interval
●Wiper operation when the washer is being used (delay until drip prevention
wiper sweep occurs)
Low speed wiper operation selected, wiper operation will be switched from low
speed to intermittent wiper operation only when the vehicle is stationary.
(However, the mode cannot be switched when the adjustment dial for the intermit-
tent wiper interval is set to the lowest setting.)
Sensor sensitivity (high)
Sensor sensitivity (low)
Wash/wipe operation
Wipers operate automatically.
(After operating several times,
the wipers operate one more
time after a short delay to pre-
vent dripping.)

172
2-3. Operating the lights and windshield wipers
IS350/250_U
■Rain drop sensor (vehicles with rain-sensing windshield wipers)
●If the wiper switch is turned to the “AUTO” position while the “ENGINE START
STOP” switch is in IGNITION ON mode, the wiper will operate once to show
that auto mode is activated.
●If the temperature of the raindrop sensor is 194°F (90°C) or higher, or -22°F
(-30°C) or lower, automatic operation may not occur. In this case, operate the
wipers in any mode other than “AUTO”.
■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 4 9 )
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 subjected vibration in “AUTO” mode. Take care that your fingers etc.
do not become caught in the windshield wipers.
●The sensor judges the amount of rain-
drops.

174
2-3. Operating the lights and windshield wipers
IS350/250_U
Headlight cleaner switch∗
■The headlight cleaner can be operated 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 with the “ENGINE
START STOP” switch in IGNITION ON mode and the headlights on, the headlight
cleaner will operate once. (→P. 1 6 9 )
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

180
2-4. Using other driving systems
IS350/250_U
■Selecting cruise mode
Selecting vehicle-to-vehicle dis-
tance control mode
Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Selecting conventional con-
stant speed control mode Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Vehicle-to-vehicle distance con-
trol mode is always reset when
the “ENGINE START STOP”
switch is switched to IGNITION
ON mode.
Switch to constant speed
control mode.
(Push and hold for approxi-
mately one second.)

182
2-4. Using other driving systems
IS350/250_U
■Canceling and resuming the speed setting
Cancel
Push the lever towards you to
cancel cruise control.
The setting is also canceled
when the brakes are applied.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
■Changing the vehicle- to-vehicle distance
Each push of the switch changes
the vehicle-to-vehicle distance
Long
Medium
Short
The vehicle-to-vehicle distance
is automatically set to the long
mode when the “ENGINE
START STOP” switch is
switched to IGNITION ON
mode.
A mark will be displayed to indi-
cate the presence of the vehicle
if a vehicle is running ahead of
you.
Preceding
vehicle mark

196
2-4. Using other driving systems
IS350/250_U
Driving assist systems
To help enhance driving safety and performance, the following systems
operate automatically in response to various driving situations. Be aware,
however, that these systems are supplementary and should not be relied
upon too heavily when operating the vehicle.
■ ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if
the brakes are applied while driving on a slippery road surface.
■Brake assist
Generates an increased level of braking force after the brake pedal is
depressed, when the system detects a panic stop situation.
■VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Maintains drive power and prevents the rear wheels (2WD models) or all
wheels (AWD models) from spinning wh en starting the vehicle or acceler-
ating on slippery roads.
■ Hill-start assist control (vehicles with an automatic transmission)
Prevents the vehicle from rolling backwards when starting on an incline or
slippery slope.
■EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn
the steering wheel.

197
2-4. Using other driving systems
2
When driving
IS350/250_U
When the VSC/TRAC/hill-start assist control systems are operatingIf 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)
Provides integrated control of the ABS, brake assist, 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. 2 0 2

199
2-4. Using other driving systems
2
When driving
IS350/250_U
■Reactivation of the TRAC/VSC systems after turning off the engine
Turning off the engine after turning off the TRAC/VSC systems 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, 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.

200
2-4. Using other driving systems
IS350/250_U
■Hill-start assist control is operational when
●The shift lever is in the D or S position.
●The brake pedal is not depressed.
■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, TRAC or hill start assist control function.
Contact your Lexus dealer.
CAUTION
■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 surfaces

217
2-5. Driving information
2
When driving
IS350/250_U
NOTICE
■Dinghy towing direction
■To prevent the steering from locking
Ensure the “ENGINE START STOP” switch is in ACCESSORY mode.
Do not tow the vehicle backwards.
Doing so may cause serious damage.