Page 176 of 573
1754-3. Operating the lights and wipers
4
Driving
IS350/250_U (OM53758U)
■Light reminder buzzer
A buzzer sounds when the engine switch is turned off or turned to ACCESSORY mode
and the driver’s door is opened while the lights are turned on.
■Operation guide display (vehicles with rain-sensing windshield wipers only)
When the headlight switch is operated to and from the “AUTO” position, the current sta-
tus is displayed on the meters for a few seconds to show that AUTO mode is activated/
deactivated. (P. 8 9 )
■Customization
Settings (e.g. light sensor se nsitivity) can be changed.
(Customizable features: P. 5 2 5 )
NOTICE
■To prevent battery discharge
Do not leave the lights on longer than ne cessary when the engine is not running.
Page 179 of 573

1784-3. Operating the lights and wipers
IS350/250_U (OM53758U)
■The Automatic High Beam can be operated when
The engine switch is in IGNITION ON mode.
■Camera sensor dete ction information
●High beam may not be automatically tu rned off in the following situations:
• When oncoming vehicles sudd enly appear from a curve
• When the vehicle is cut in front of by another vehicle
• When oncoming or preceding vehicles are hidden from sight due to repeated
curves, road dividers or roadside trees
●High beam may be turned off if an oncoming vehicle that is using fog lights without
using the headlights is detected.
●House lights, street lights, red traffic signals, and illuminated billboards or signs may
cause the high beam to turn off.
●The following factors may affect the amount of time taken to turn high beam on or off:
• The brightness of headlights, fog lights, and tail lights of oncoming and preceding
vehicles
• The movement and direction of oncoming and preceding vehicles
• When an oncoming or preceding vehicle only has operational lights on one side
• When an oncoming or preceding vehicle is a two-wheeled vehicle
• The condition of the road (gradient, curve, condition of the road surface etc.)
• The number of passengers and amount of luggage
●High beam may be turned on or off when unexpected by the driver.
●Small vehicles, such as bicy cles, may not be detected.
●In the situations below, the system may not be able to correctly detect the surrounding
brightness levels, and may flash or expose nearby pedestrians to the high beam. There-
fore, you should consider turning the high be ams on or off manually rather than relying
on the Automatic High Beam system.
• In bad weather (rain, snow, fog, sandstorms etc.)
• The windshield is obscured by fog, mist, ice, dirt etc.
• The windshield is cracked or damaged.
• The camera sensor is deformed or dirty.
• Surrounding brightness levels are equal to those of headlights, tail lights or fog lights.
• Vehicles ahead have headlights or tail lights that are either switched off, dirty, chang-
ing color, or have improperly adjusted aim.
• When driving through an area of intermit tently changing brightness and darkness.
• When frequently and repeatedly driving ascending/descending roads, or roads with
rough, bumpy or uneven surfaces (such as stone-paved roads, gravel tracks etc.).
• When frequently and repeat edly taking curves or driving on a winding road.
• There is a highly reflective object ahead of the vehicle, such as a sign or a mirror.
• The vehicle’s headlights are damaged or dirty.
• The vehicle is listing or titling, due to a flat tire, a trailer being towed etc.
• The driver believes that the high beam may be causing problems or distress to other
drivers or pedestrians nearby.
Page 180 of 573
1794-3. Operating the lights and wipers
4
Driving
IS350/250_U (OM53758U)
■Temporarily lowering sensor sensitivity
The sensitivity of the sensor can be temporarily lowered.Turn the engine switch off while the following conditions are met.
• The headlight switch is in or .
• The headlight switch lever is in high beam position.
• Automatic High Beam switch is on. Turn the engine switch to IGNITION ON mode.
Within 5 seconds after , repeat pulling th e headlight switch lever to the original
position then pushing it to the high beam position quickly 9 times, then leave the
lever in high beam position.
Automatic High Beam (headlights) may turn on even the vehicle is stopped.
CAUTION
■Limitations of the Automatic High Beam
Do not rely on the Automatic High Beam. Always drive safely, taking care to observe
your surroundings and turning high beam on or off manually if necessary.
1
2
32
Page 201 of 573

2004-5. Using the driving support systems
IS350/250_U (OM53758U)
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 400 ft. (120 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 control.
Example of deceleration cruising
When the vehicle ahead is driving slower than the set speed
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. A warning tone warns yo u when the system cannot decelerate suf-
ficiently to prevent your vehicle from closing in on the vehicle ahead.
Example of follow-up cruising
When following a vehicle driving slower than the set speed
The system continues follow-up cruising wh ile adjusting for changes in the speed of
the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by the driver.
Example of acceleration
When there are no longer any vehicles ahead 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
1
2
3
4
Page 202 of 573

2014-5. Using the driving support systems
4
Driving
IS350/250_U (OM53758U)
When your vehicle is too close to a vehicle ahead, and sufficient automatic
deceleration via the cruise control is not possible, the display will flash and the
buzzer will sound to alert the driver. An ex ample of this would be if another driver
cuts in front of you while you are followi ng a vehicle. Apply the brakes to ensure
an appropriate vehicle-to-vehicle distance.
■Warnings may not occur when
In the following instances, there is a po ssibility that the warnings will not occur:
●When the speed of the vehicle ahead matches or exceeds your vehicle
speed
●When the vehicle ahead is traveling at an extremely slow speed
●Immediately after the cruise control speed was set
●At the instant the accelerator is applied
When constant speed control mode is sele cted, your vehicle will maintain a set
speed without controlling the vehicle-to-vehicle distance. Select this mode only
when vehicle-to-vehicle distance contro l mode does not function correctly due
to dirt etc.
Press the “ON/OFF” button to acti-
vate the cruise control.
Press the button again to deactivate the
cruise control.
Switch to constant speed control
mode.
(Push the lever forward and hold for
approximately one second.)
Constant speed control mode indicator will come on.
When in constant speed control mode, to return to vehicle-to-vehicle distance con-
trol mode, push the lever forward agai n and hold for approximately 1 second.
After the desired speed has been set, it is not possible to return to vehicle-to-vehicle
distance control mode.
If the engine switch is turned off and then turned to IGNITION ON mode again, the
vehicle will automatically return to vehicle-to-vehicle distance control mode.
Adjusting the speed setting: P. 1 9 3
Canceling and resuming the speed setting: P. 1 9 3
Approach warning
Selecting conventional constant speed control mode
1
2
Page 204 of 573
2034-5. Using the driving support systems
4
Driving
IS350/250_U (OM53758U)
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle dis-
tance control operates properly. (Some obstructions, such as snow, ice and plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is cancel ed if an obstruction is detected.
■Operation guide display
When the dynamic radar cruise control switch is operated, a guidance display is shown
on the meters for a few seconds as to how to operate the dynamic radar cruise control
switch or distance switch. ( P. 8 9 )
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need fo r caution while driving. (P. 4 6 5 )
Grille cover
Radar sensor
1
2
Page 206 of 573

2054-5. Using the driving support systems
4
Driving
IS350/250_U (OM53758U)
CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not appropriate,
adjust the vehicle speed, as well as the distance between your vehicle and vehicles
ahead by applying the brakes etc.
■Cautions regarding the driving assist systems
Observe the following precautions.
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 intended 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 al lows 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 judge proper following distance
The dynamic radar cruise control determines whether the following distance
between the driver’s own vehicle and a designated vehicle traveling ahead is appro-
priate or not. It is not capable of making an y 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 control has no capa bility 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 vehicl e and act appropriately in order to ensure
the safety of all involved.
■To avoid inadvertent cruise control activation
Switch the cruise control off using th e “ON/OFF” button when not in use.
Page 209 of 573
2084-5. Using the driving support systems
IS350/250_U (OM53758U)
While driving on a road that has lane markers, this system recognizes the lane
markers using a camera as a sensor to alert the driver when the vehicle deviates
from its lane.
If the system judges that the vehicle has deviated from its lane, it alerts the driver
using a buzzer and indications on the multi-information display.
Camera sensor
LDA (Lane Departure Alert)
: If equipped
Summary of function