2017 Lexus IS350 Owner's Manual / LEXUS 2017 IS200T,IS300,IS350 OWNER'S MANUAL (OM53D76U)

2334-5. Using the driving support systems
4
Driving
IS350/300/200t_U (OM53D76U)
■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, operat ion of the function is auto-
matically restored. ( →P. 232)
■Steering control function
Depending on the vehicle speed, lane depart ure 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 f eel steering wheel vibrations due to the road conditions, etc.
■Hands off steering wheel alert
When the system determines that the driver has removed the hands from the steering
wheel while the steering control function is operating, a warning message is displayed 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.

2344-5. Using the driving support systems
IS350/300/200t_U (OM53D76U)
■Conditions in which functions may not operate properly
In the following situations, the camera sensor may not detect white (yellow) lines and var-
ious functions may not operate normally.
●There are shadows on the road that run parallel with, or cover, the white (yellow) lines.
●The vehicle is driven in an ar ea without white (yellow) lines, such as in front of a tollgate
or checkpoint, or at an intersection, etc.
●The white (yellow) lines are cracked, “Botts ’ dots”, “Raised pavement marker” or stones
are present.
●The white (yellow) lines cannot be seen or are difficult to see due to sand, etc.
●The vehicle is driven on a road surface that is wet due to rain, puddles, etc.
●The traffic lines are yellow (which may be more difficult to recognize than lines that are
white).
●The white (yellow) lines cross over a curb, etc.
●The vehicle is driven on a bright surface, such as concrete.
●The vehicle is driven on a surface that is bright due to reflected light, etc.
●The vehicle is driven in an area where the brightness changes suddenly, such as at the
entrances and exits of tunnels, etc.
●Light from the headlights of an oncoming vehicle, the sun, etc. enters the camera.
●The vehicle is driven where the road diverges, merges, etc.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which tilts left or right, or a winding road.
●The vehicle is driven on an unpaved or rough road.
●The vehicle is driven around a sharp curve.
●The traffic lane is excessively narrow or wide.
●The vehicle is extremely tilted due to carry ing heavy luggage or having improper tire
pressure.
●The distance to the preceding vehicle is extremely short.
●The vehicle is moving up and down a large am ount due to road conditions during driv-
ing (poor roads or road seams).
●The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis
has deviated.
●The vehicle is struck by a crosswind.
●The vehicle has just changed lane s or crossed an intersection.
●Snow tires, etc. are equipped.

2354-5. Using the driving support systems
4
Driving
IS350/300/200t_U (OM53D76U)
■Warning message
Warning messages are used to indicate a system malfunction or to inform the driver of
the need for caution while driving. ( →P. 522)
■Customization
→P. 92

2364-5. Using the driving support systems
IS350/300/200t_U (OM53D76U)
In vehicle-to-vehicle distance control mode, the vehicle automatically a\
cceler-
ates and decelerates to match the speed changes of the preceding vehicle even
if the accelerator pedal is not depressed. In constant speed control mode, the
vehicle runs at a fixed speed.
Use the dynamic radar cruise control on freeways and highways.
●Vehicle-to-vehicle distance control mode ( →P. 239)
●Constant speed control mode ( →P. 244)
Vehicle-to-vehicle distance button
Display
Set speed
Indicators
Cruise control switch
Dynamic radar cruise control
Summary of functions
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2374-5. Using the driving support systems
4
Driving
IS350/300/200t_U (OM53D76U)
WARNING
■Before using dynamic radar cruise control
Driving safely is the sole responsibility of th e driver. Do not rely solely on the system,
and drive safely by always paying careful attention to your surroundings.
The dynamic radar cruise control provides driving assistance to reduce the driver’s
burden. However, there are limitations to the assistance provided.
Even when the system is functioning normally, the condition of the preceding vehicle as
detected by the system may differ from the condition observed by the driver. There-
fore, the driver must always remain alert, assess the danger of each situation and drive
safely. Relying on this system or assuming the system ensures safety while driving can
lead to an accident, resultin g in death or serious injury.
■Cautions regarding the driving assist systems
Observe the following precautions, as there are limitations to the assistance provided
by the system.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control is only in tended to help the driver in determining
the following distance between the driver ’s own vehicle and a designated vehicle
traveling ahead. It is not a mechanism that allows careless or inattentive driving, and it
is not a system that can assist the driver in low-visibility conditions . It is still necessary
for driver to pay close attention to the vehicle’s surroundings.
●Assisting the driver to judg e proper following distance
The dynamic radar cruise control determines whether the following distance
between the driver’s own vehicle and a design ated vehicle traveling ahead is within a
set range. It is not capable of making any other type of judgement. Therefore, it is
absolutely necessary for the driver to remain vigilant and to determine whether or not
there is a possibility of danger in any given situation.
●Assisting the driver to operate the vehicle
The dynamic radar cruise cont rol has limited capability to prevent or avoid a collision
with a vehicle traveling ahead. Therefore, if there is ever any danger, the driver must
take immediate and direct control of the vehicle and act appropriately in order to
ensure the safety of all involved.
■To avoid inadvertent dynamic radar cruise control activation
Switch the dynamic radar cruise control o ff using the “ON/OFF” button when not in
use.

2384-5. Using the driving support systems
IS350/300/200t_U (OM53D76U)
WARNING
■Situations unsuitable for dy namic radar cruise control
Do not use dynamic radar cruise contro l in any of the following situations.
Doing so may result in inappropriate speed control and could cause an accident result-
ing in death or serious injury.
●Roads where there are pede strians, cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as thos e covered with rain, ice or snow
●On steep downhills, or where there are sudden changes between sharp up and down
gradients
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad enough that they may prevent the sensors from
detecting correctly (fog, snow, sandstorm, heavy rain, etc.)
●When there is rain, snow, etc. on the fron t surface of the radar sensor or camera sen-
sor
●In traffic conditions that require frequent repeated a cceleration and deceleration
●During emergency towing
●When an approach warning buzzer is heard often

2394-5. Using the driving support systems
4
Driving
IS350/300/200t_U (OM53D76U)
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle
following distance, and operates to main tain a suitable following distance from
the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long downhill
slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance button.
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes (the stop lights will come on at this time). The system will respond to
changes in the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle
distance set by the driver. Approach warning warns you when the system cannot
decelerate sufficie ntly to prevent your vehicle from closing in on the vehicle ahead.
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed
The system accelerates until the set speed is reached. The system then returns to con-
stant speed cruising.
Driving in vehicle-to-vehicle distance control mode
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2404-5. Using the driving support systems
IS350/300/200t_U (OM53D76U)
Press the “ON/OFF” button to acti-
vate the cruise control.
Radar cruise control indicator will come
on and a message will be displayed on
the multi-information display.
Press the button again to deactivate the
cruise control.
If the “ON/OFF” button is pressed and
held for 1.5 seconds or more, the system
turns on in constant speed control
mode. ( →P. 244)
Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (above
approximately 30 mph [50 km/h])
and push the lever down to set the
speed.
Cruise control “SET” indicator will come
on.
The vehicle speed at the moment the
lever is released becomes the set speed.
Setting the vehicle speed (vehicle-to-vehicle distance control mode)
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