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2494-5. Using the driving support systems
4
Driving
IS350 AWD/IS350/IS300 AWD/IS300_U
WARNING
■Before using dynamic radar cruise control
●Driving safely is the sole responsibility of the 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 limitatio ns to the assistance provided.
Read the following conditions carefully. Do not overly rely on this system and always
drive carefully.
• When the sensor may not be correctly detecting the vehicle ahead: P. 258
• Conditions under which the vehicle-to-vehicle distance control mode may not function correctly: P. 259
●Set the speed appropriately depending on the speed limit, traffic flow, road condi-
tions, weather conditions, etc. The driver is responsible for checking the set speed.
●Even when the system is functioning norma lly, the condition of the preceding vehicle
as detected by the system may differ from the condition observed by the driver.
Therefore, 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, resulting in death or serious injury.
●Switch the dynamic radar cruise control off using the “ON/OFF” button when not in
use.
■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.
Page 250 of 660

2504-5. Using the driving support systems
IS350 AWD/IS350/IS300 AWD/IS300_U
WARNING
■Situations unsuitable for dy namic radar cruise control
Do not use dynamic radar cruise control 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 pedestrians, cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those 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 acceleration and deceleration
●During emergency towing
●When an approach warning buzzer is heard often
Page 252 of 660
2524-5. Using the driving support systems
IS350 AWD/IS350/IS300 AWD/IS300_U
Press the “ON/OFF” button to acti-
vate the cruise control.
Dynamic radar cruise control indicator
will come on and a message will be dis-
played 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. 256)
Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or 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)
1
2
Page 254 of 660

2544-5. Using the driving support systems
IS350 AWD/IS350/IS300 AWD/IS300_U
Pressing the switch changes the vehi-
cle-to-vehicle distance as follows: Long
Medium
Short
The vehicle-to-vehicle distance is set
automatically to long mode when the
engine switch is turned to IGNITION
ON mode.
If a vehicle is running ahead of you, the pr eceding vehicle mark will also be displayed.
Select a distance from the table below. Note that the distances shown corre-
spond to a vehicle speed of 50 mph (8 0 km/h). Vehicle-to-vehicle distance
increases/decreases in accord ance with vehicle speed.
Pulling the lever toward you cancels
the speed control.
The speed control is also canceled when
the brake pedal is depressed.
Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.
However, cruise control does not
resume when the vehicle speed is
approximately 25 mph (40 km/h) or
less.
Changing the vehicle-to-vehicle distance (vehicle-to-vehicle distance
control mode)
Preceding
vehicle mark
1
2
3
Vehicle-to-vehicle distance settings (vehicle-to-vehicle distance con-
trol mode)
Distance optionsVehicle-to-vehicle distance
LongApproximately 160 ft. (50 m)
MediumApproximately 130 ft. (40 m)
ShortApproximately 100 ft.(30 m)
Canceling and resuming the speed control
1
2
Page 255 of 660
2554-5. Using the driving support systems
4
Driving
IS350 AWD/IS350/IS300 AWD/IS300_U
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 example of this would be if another
driver cuts in front of you while you are
following a vehicle. Depress the brake
pedal to ensure an appropriate vehicle-
to-vehicle distance.
■Warnings may not occur when
In the following instances, warnings ma y not occur even when the vehicle-to-
vehicle distance is small.
●When the speed of the preceding vehicle matches or exceeds your vehicle
speed
●When the preceding vehicle is traveling at an extremely slow speed
●Immediately after the crui se control speed was set
●When depressing the accelerator pedal
Approach warning (vehicle-to-vehicle distance control mode)
Page 256 of 660

2564-5. Using the driving support systems
IS350 AWD/IS350/IS300 AWD/IS300_U
When constant speed control mode is se lected, your vehicle will maintain a set
speed without controlling the vehicle-to-veh icle distance. Select this mode only
when vehicle-to-vehicle distance control mode does not function correctly due
to a dirty radar sensor, etc.
With the cruise control off, press and
hold the “ON/OFF” button for 1.5
seconds or more.
Immediately after the “ON/OFF” but-
ton is pressed, the dynamic radar cruise
control indicator will come on. After-
wards, it switches to the cruise control
indicator.
Switching to constant speed control
mode is only possible when operating
the lever with the cruise control off.
Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or 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.
Adjusting the speed setting: P. 253
Canceling and resuming the speed setting: P. 254
Selecting constant speed control mode
1
2
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2574-5. Using the driving support systems
4
Driving
IS350 AWD/IS350/IS300 AWD/IS300_U
■Dynamic radar cruise control can be set when
●The shift lever is in D.
●Range 4 or higher of D has been selected by using the paddle shift switch.
●Vehicle speed is at or above approximately 30 mph (50 km/h).
■Accelerating after setting the vehicle speed
The vehicle can accelerate by operating the accelerator pedal. After accelerating, the
set speed resumes. However, during vehicle-to-vehicle distance control mode, the vehi-
cle speed may decrease below the set speed in order to maintain the distance to the pre-
ceding vehicle.
■Automatic cancelation of vehicle- to-vehicle distance control mode
Vehicle-to-vehicle distance control mode is automatically canceled in the following situ-
ations:
●Actual vehicle speed falls at or below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off.
●When snow mode is set.
●The sensor cannot detect correctly because it is covered in some way.
●Pre-collision braking is activated.
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-
son, there may be a malfunction in th e system. Contact your Lexus dealer.
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatica lly canceled in the following situations:
●Actual vehicle speed is more than approxim ately 10 mph (16 km/h) below the set vehi-
cle speed.
●Actual vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off.
●Pre-collision braking is activated.
If constant speed control mode is automati cally canceled for any other reason, there may
be a malfunction in the system . Contact your Lexus dealer.
■Brake system operation sound
If the brakes are applied automatically while the vehicle is in vehicle-to-vehicle distance
control mode, a brake system operation soun d may be heard. This does not indicate a
malfunction.
■Warning messages and buzzers fo r dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for ca ution while driving. If a warning message is shown on the
multi-information display, read the message and follow the instructions.
Page 540 of 660
5408-2. Steps to take in an emergency
IS350 AWD/IS350/IS300 AWD/IS300_U
Indicates a malfunction in the vehicle’s charging system.
Immediately stop the vehicle in a safe place and
contact your Lexus dealer. Continuing to drive the
vehicle may be dangerous.
Indicates that the radar sensor is dirty or covered with
ice A buzzer also sounds.
Clean the sensor.
Indicates that the dynamic radar cruise control system
cannot be used temporarily due to bad weather
A buzzer also sounds.
Use the dynamic radar cruise control system when
it becomes available again.
Warning messageDetails/Actions
(F SPORT
models)