stop start Lexus IS250 2012 Service Manual

175
2-3. Operating the lights and windshield wipers
2
When driving
IS350/250_U
■Automatic light off system
This system is active when the “ENGINE START STOP” switch is in IGNITION
ON mode and the headlight lever is in any position other than
or .
●When the headlights come on: The headlights and tail lights turn off 30 seconds
after a door is opened and closed if the “ENGINE START STOP” switch has
been switched to ACCESSORY mode or turned OFF. (The lights turn off
immediately if on the key is pressed after all doors are locked.)
●When only the tail lights come on: The tail lights turn off automatically if the
“ENGINE START STOP” switch is switched to ACCESSORY mode or turned
OFF and driver’s door is opened.
To turn the lights on again, switch to IGNITION ON mode, or turn the light switch
off once and then back to or
.
■Automatic headlight leveling system (vehicles with discharge headlights)
The level of the headlights is automatically adjusted according to the number of
passengers and the loading condition of the vehicle to ensure that the headlights do
not interfere with other road users.
■Customization that can be configured at Lexus dealer
Settings (e.g. light sensor sensitivity) can be changed.
(Customizable features →P. 553)
NOTICE
■To prevent battery discharge
Do not leave the lights on longer than necessary when the engine is not running.

182
2-3. Operating the lights and windshield wipers
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)
Washer/wiper operation
Wipers operate automatically.
(After operating several times,
the wipers operate one more
time after a short delay to pre-
vent dripping.)

183
2-3. Operating the lights and windshield wipers
2
When driving
IS350/250_U
■Raindrop 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
If there is washer fluid in the windshield washer fluid reservoir and no washer fluid
sprays, the nozzle may be blocked. In this case, contact your Lexus dealer.
■Customization that can be configured at Lexus dealer
Settings (e.g. drip prevention function) can be changed.
(Customizable features →P. 553)
●The sensor judges the amount of rain-
drops.

185
2-3. Operating the lights and windshield wipers
2
When driving
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 7 8 )
■When using the headlight cleaner
The washer fluid will spray out into the surrounding area and may get on clothes,
items etc. Therefore, check the surrounding area before using the headlight
cleaner.
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

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)
Helps to prevent the vehicle from rolling backward 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 operatingThe slip indicator light flashes to
indicate that the VSC/TRAC/hill-
start assist control systems have
been engaged.
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.
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, engine output and steering assist.

199
2-4. Using other driving systems
2
When driving
IS350/250_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, TRAC 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 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 when 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.
●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, 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 may 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

213
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.

224
3-1. Using the air conditioning system and defogger
IS350/250_U
Rear window and outside rear view mirror defoggers
■The defogger can be operated when
The “ENGINE START STOP” switch is in IGNITION ON mode.
CAUTION
■When the outside rear view mirror defoggers are on
Do not touch the outside surface of the rear view mirror, as it can become very hot
and burn you.
These features are used to defog the rear window, and to remove rain-
drops, dew and frost from the outside rear view mirrors.
With navigation system
Owners of models equipped with a navigation system should refer to the
“Navigation System Owner's Manual”.
Without navigation systemOn/off
The defoggers will automatically
turn off after 15 to 60 minutes.
The operation time changes
according to the ambient tem-
perature and vehicle speed.