steering Lexus IS200t 2017 s Workshop Manual

2614-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
◆Steering control function
When the system determines that
the vehicle might depart from its
lane, the system provides assistance
as necessary by operating the steer-
ing wheel in small amounts for a
short period of time to keep the
vehicle in its lane.
Except for Israel: If the system
detects that the steering wheel has
not been operated for a fixed amount
of time or the steering wheel is not
being firmly gripped, a warning is dis-
played on the multi-information dis-
play and the function is temporarily
canceled.
For Israel: If the system detects that
the steering wheel has not been
operated for a fixed amount of time
or the steering wheel is not being
firmly gripped, a warning is displayed
on the multi-information display and
the warning buzzer sounds.
◆Vehicle sway warning function
When the vehicle is swaying or
appears as if it may depart from its
lane multiple times, the warning
buzzer sounds and a message is dis-
played on the multi-information dis-
play to alert the driver.

2624-5. Using the driving support systems
IS200t_EE(OM53D77E)
WARNING
■Before using LDA system
Do not rely solely upon the LDA system. The LDA system does not automatically drive
the vehicle or reduce the amount of attention that must be paid to the area in front of
the vehicle. The driver must always assume full responsibility for driving safely by pay-
ing careful attention to the surrounding conditions and operating the steering wheel to
correct the path of the vehicle. Also, the driver must take adequate breaks when
fatigued, such as from driving for a long period of time.
Failure to perform appropriate driving operat ions and pay careful attention may lead to
an accident, resulting in death or serious injury.
■To avoid operating LDA system by mistake
When not using the LDA system, use the LDA switch to turn the system off.
■Situations unsuitable for LDA system
Do not use the LDA system in the following situations.
The system may not operate properly and le ad to an accident, resulting in death or
serious injury.
●A spare tire, tire chains, etc. are equipped.
●When the tires have been excessively worn, or when the tire inflation pressure is low.
●Tires which differ by structure, manufacturer, brand or tread pattern are used.
●Objects or patterns that could be mistaken for white (yellow) lines are present on the
side of the road (guardrails, cu rbs, reflective poles, etc.).
●Vehicle is driven on a snow-covered road.
●White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.
●Asphalt repair marks, white (yellow) line ma rks, etc. are present due to road repair.
●Vehicle is driven in a temporary lane or restricted lane due to construction work.
●Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,
freezing, etc.
●Vehicle is driven in traffic lanes other than on highways and freeways.
●Vehicle is driven in a construction zone.
●When your vehicle is towing a trailer or during emergency towing
■Preventing LDA system malfunctions and operations performed by mistake
●Do not modify the headlights or place sticke rs, etc. on the surface of the lights.
●Do not modify the suspension etc. If the suspension etc. needs to be replaced, con-
tact any authorized Lexus retailer or Le xus authorized repairer, or any reliable
repairer.
●Do not install or place anything on the hood or grille. Also, do not install a grille guard
(bull bars, kangaroo bar, etc.).
●If your windshield needs repairs, contac t any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.

2644-5. Using the driving support systems
IS200t_EE(OM53D77E)
LDA indicator
The illumination condition of the
indicator informs the driver of the
system operation status.
Illuminated in white:
LDA system is operating.
Illuminated in green:
Steering wheel assistance of the steer-
ing control function is operating.
Flashing in orange:
Lane departure alert function is operat-
ing.
Operation display of steering wheel
operation support
Indicates that steering wheel assistance of the steering control function is
operating.
Lane departure alert function display
Displayed when the multi-information display is switched to the driving assist
system information screen.
Indications on multi-information display
1
2
3
Inside of displayed white lines is
whiteInside of displayed white lines is
black
Indicates that the system is recognizing
white (yellow) lines. When the vehicle
departs from its lane, the white line dis-
played on the side the vehicle departs
from flashes orange. Indicates that the system is not able to
recognize white (yellow) lines or is
temporarily canceled.

2654-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
■Operation conditions of each function
●Lane departure alert function
This function operates when all of the following conditions are met.
• LDA is turned on.
• Vehicle speed is approximately 50 km/h (32 mph) or more.
• System recognizes white (yellow) lines.
• Width of traffic lane is approx imately 3 m (9.8 ft.) or more.
• Turn signal lever is not operated.
• Vehicle is driven on a stra ight road or around a gentle curve with a radius of more
than approximately 150 m (492 ft.).
• No system malfunctions are detected. ( P. 554)
●Steering control function
This function operates when all of the follo wing conditions are met in addition to the
operation conditions for the lane departure alert function.
• Setting for Steering Assist in of the multi-information display is set to On. (P.
107)
• Vehicle is not accelerated or decelerated by a fixed amount or more.
• Steering wheel is not operat ed with a steering force level suitable for changing
lanes.
• ABS, VSC, TRC and PCS are not operating.
• TRC or VSC is not turned off.
• Except for Israel: Hands off steering wheel alert is not displayed. ( P. 266)
●Vehicle sway warning
This function operates when all of the following conditions are met.
• Setting for Sway Warning in of the multi-information display is set to On.
( P. 107)
• Vehicle speed is approximately 50 km/h (32 mph) or more.
• Width of traffic lane is approx imately 3 m (9.8 ft.) or more.
• No system malfunctions are detected. ( P. 554)

2664-5. Using the driving support systems
IS200t_EE(OM53D77E)
■Temporary cancellation of functions
When operation conditions are no longer met, a function may be temporarily canceled.
However, when the operation conditions are met again, operation of the function is auto-
matically restored. (P. 265)
■Steering control function
Depending on the vehicle speed, lane departure situation, road conditions, etc., the
driver may not feel the function is operating or the function may not operate at all.
■Lane departure alert function
The warning buzzer may be difficult to hear due to external noise, audio playback, etc.
Also, it may be difficult to feel steering wh eel vibrations due to the road conditions, etc.
■Hands off steering wheel alert
Except for Israel: When the system determines that the driver has removed the hands
from the steering wheel while the steering cont rol function is operating, a warning mes-
sage is displayed on the multi-information display.
If the driver continues to keep the hands off of the steering wheel, the buzzer sounds, a
warning message is displayed and the function is temporarily canceled. This alert also
operates in the same way when the vehicle is driven with the steering wheel lightly
gripped. However, depending on the road conditions, etc., the function may not cancel.
For Israel: When the system determines that the driver has removed the hands from the
steering wheel while the steering control functi on is operating, a warning message is dis-
played on the multi-information display and the buzzer sounds.
■White (yellow) lines are only on one side of road
The LDA system will not operate for the side on which white (yellow) lines could not be
recognized.

2734-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
●Side road speed signs may be detected and displayed (if positioned in sight of the cam-
era sensor) while the vehicle is traveling on the main road.
●Roundabout exit road speed signs may be detected and displayed (if positioned in sight
of the camera sensor) while traveling on a roundabout.
■When driving vehicle in country with different speed unit
Since RSA recognizes signs based on the set unit of the meter, it is necessary to change
the set unit of the meter. Adjust the set unit of the meter to the speed unit of signs in the
current location. ( P. 641)
■Turning the system on/off
■Speed limit sign display
If the engine switch was last turned off while a speed limit sign was displayed on the multi-
information display, the same sign displays again when the engine switch is turned to
IGNITION ON mode.
■Customization
Setting (e.g. speeding warning threshold) can be changed.
(Customizable feature: P. 107)
Select
on the settings display
(  P. 97)
Press on the steering wheel.
1
2

2854-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
■Conditions under which the vehicle-to-vehicle distan ce control mode may not function
correctly
In the case of the following conditions, op erate the brake pedal (or accelerator pedal,
depending on the situation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system may not
operate properly.
●When the vehicle ahead of you decelerates suddenly
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage com-
partment, etc.)
●Preceding vehicle has an extremely high
ground clearance
●When the road curves or when the lanes are
narrow
●When steering wheel operation or your posi-
tion in the lane is unstable

2934-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
After the engine is stopped by the Stop & Start system when the vehicle is on an
incline, brake force is temporarily maintained to prevent rolling backwards until
the engine is restarted and drive force is generated.
When drive force is generated, the ma intained brake force is automatically
canceled.
●This function operates on flat surfaces as well as steep inclines.
●Sound may be generated from the brak es, but this is not a malfunction.
●Brake pedal response may change and vibration may occur, but these are not
malfunctions.
■Operating conditions
●The Stop & Start system is operational when all of the following conditions are met:
• The brake pedal is being depressed firmly.
• The shift lever is in D or P.
• Normal mode or Eco drive mode is selected as the driving mode.
• is off.
• The driver’s seat belt is fastened.
• The engine is adequately warmed up.
• The driver’s door is closed.
• The accelerator pedal is not being depressed.
• The outside temperature is -5°C (23°F) or higher.
• The hood is closed.
●In the following situations the engine may not be stopped by the Stop & Start system.
This is not a malfunction of the Stop & Start system.
• The air conditioning system is being used when the ambient temperature is high or
low.
• The battery is not sufficiently charged, such as if the vehicle has been parked for a long time and the battery charge has decreased, the electric load is large, the bat-
tery temperature is excessively low or the battery has deteriorated, or is undergoing
a periodic recharge.
• The brake booster vacuum is low.
• The vehicle is stoppe d on a steep incline.
• The steering wheel is being operated.
• Due to traffic or other circumstances the vehicle is stopped repeatedly.
• The vehicle is being driven in a high altitude area.
• Engine coolant temperature or transmissi on fluid temperature is extremely low or
high.
• The battery fluid temperature is extremely low or high.
• For a while after the battery terminals have been disconnected and reconnected.
• For a while after the battery has been replaced.
• Vehicles with a power heater: The power heater is being used.
Hill-start assist control

2944-5. Using the driving support systems
IS200t_EE(OM53D77E)
●In the following situations, the engine will restart automatically if the engine is stopped
by the Stop & Start system. (To enable stoppi ng of the engine by the Stop & Start sys-
tem, drive the vehicle.)
• The air conditioning system is turned on.
• is turned on.
• The steering wheel is operated.
• The shift lever is shifted to M, N or R from D.
• The shift lever is shifted from P.
• Sport mode or snow mode is selected as the driving mode.
• The driver’s seat belt is unfastened.
• The driver’s door is opened.
• The accelerator pedal is depressed.
• The Stop & Start cancel switch is pressed.
• The vehicle starts to roll on an incline.
• Vehicles with a power heater: The power heater is turned on.
●In the following situations, the engine may re start automatically if the engine is stopped
by the Stop & Start system. (To enable stoppi ng of the engine by the Stop & Start sys-
tem, drive the vehicle.)
• The brake pedal is pumped or strongly depressed.
• The air conditioning system is being used.
• The battery is not sufficiently charged.
■If the steering wheel is turned shortly after the engine has started
If the steering wheel is turned shortly after the engine has been started by the Stop &
Start system, the steering wheel may feel heavy.
■Hood
●If the hood is opened while the engine is stopped by the Stop & Start system with the
shift lever in D, the engine will stall and will not be able to be restarted by the automatic
engine start function. In this case, restart the engine using the normal engine starting
procedure. ( P. 204)
●If the hood is opened while the engine is stopped by the Stop & Start system with the
shift lever in P, the engine will be restarted automatically.
●Even if the hood is closed after the engine is started with the hood open, the Stop &
Start system will not operate. Close the hood, turn the engine switch off, wait 30 sec-
onds or more, and then start the engine.
■When to use the Stop & Start system
●When the system does not operate, is canceled, or is malfunctioning, warning mes-
sages and a warning buzzer are used to inform the driver. ( P. 296)
●If the engine switch is pressed when the en gine is stopped by the Stop & Start system,
the engine will stall and will not be able to be restarted by the automatic engine start
function. In this case, restart the engine using the normal engine starting procedure.
(  P. 204)
●When the engine is restarted by the Stop & Start system, the power outlet may be tem-
porarily unusable, but this is not a malfunction.
●Installation and removal of electrical components and wireless devices may affect the
Stop & Start system. Contact any authorized Lexus retailer or Lexus authorized
repairer, or any reliable repairer for details.

2974-5. Using the driving support systems
4
Driving
IS200t_EE(OM53D77E)
●When the engine automatically restarts while stopped by the Stop & Start system
■Stop & Start system warning messages
If a system malfunction occurs, a warning message will be displayed on the multi-infor-
mation display to inform the driver of the need for caution. ( P. 572)
■If the Stop & Start cancel indicator continues to flash
The system may be malfunctioning. Have the vehicle inspected by any authorized Lexus
retailer or Lexus authorized repa irer, or any reliable repairer.
MessageDetails
“For Brake System.” • The vehicle is being driven in a high altitude
area.
• The brake booster vacuum is low.
When the brake booster vacuum reaches a pre-
determined level, the system will be enabled.
“Driver Seat Belt
Unbuckled.”
The driver seat belt is not fastened.
“Non-Dedicated
Battery.”
A non-dedicated battery for the Stop & Start sys-
tem may have been installed. The Stop & Start system does not operate. Have
the vehicle inspected by any authorized Lexus
retailer or Lexus authoriz ed repairer, or any reli-
able repairer.
MessageDetails
“For Climate Con-
trol.”
• The air conditioning system has been turned on or is being used.
• has been turned on.
“For Brake System.”
The brake pedal has been depressed further or
pumped. The system will be enable d after the engine runs
and the brake booster vacuum reaches a prede-
termined level.
“Battery Charging.”
The battery charge amount may be low. The engine is restarted to prioritize battery
charging. Operating the engine for a short while
allows the system to recover.
“Steering Wheel
Turned.”
The steering wheel was operated.
“Driver Seat Belt
Unbuckled.”
The driver seat belt has been unfastened.