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Driving
IS300h_EE(OM53B95E)If the power switch is turned off and then turned to ON mode again, the vehi-
cle will automatically return to vehicle-to-vehicle distance control mode.
Adjusting the speed setting:P. 246
Canceling and resuming the speed setting: P. 2 4 6
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2564-5. Using the driving support systems
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Dynamic radar cruise control can be set when
The shift lever is in D or range 4 or higher of S has been selected.
Range 4 or higher of D has been selected by using the paddle shift.
Vehicle speed is above approximately 50 km/h (30 mph).
Accelerating after setting the vehicle speed
The vehicle can accelerate normally. After acceleration, the set speed resumes.
However, during vehicle-to-vehicle distance control mode, the vehicle speed
may decrease below the set speed in order to maintain the distance to the vehicle
ahead.
Automatic cancelation of vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the fol-
lowing situations:
Actual vehicle speed falls below approximately 40 km/h (25 mph).
VSC is activated.
TRC is activated for a period of time.
When the VSC or TRC system is turned off by pressing the VSC OFF switch.
The sensor cannot operate correctly because it is covered in some way.
The windshield wipers are operating at high speed (when the wipers are in
AUTO mode or the high speed wiper operation).
When snow mode is set.
Pre-crash braking is activated.
If vehicle-to-vehicle distance control driving is automatically canceled for any
other reason, there may be a malfunction in the system. Contact any authorized
Lexus dealer or repairer, or another duly qualified and equipped professional.
Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situa-
tions:
Actual vehicle speed is more than approximately 16 km/h (10 mph) below the
set vehicle speed.
At this time, the memorized set speed is not retained.
Vehicle speed falls below approximately 40 km/h (25 mph).
VSC is activated.
TRC is activated for a period of time.
When the VSC or TRC system is turned off by pressing the VSC OFF switch.
Pre-crash braking is activated.
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Driving
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Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehi-
cle distance control operates properly. (Some obstructions, such as snow, ice and
plastic objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled 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. 1 1 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 for caution while driving. (P. 518) Grille cover
Radar sensor
1
2
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Certification
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Driving
IS300h_EE(OM53B95E)
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2604-5. Using the driving support systems
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CAUTION
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2624-5. Using the driving support systems
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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 appro-
priate, 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 deter-
mining the following distance between the driver’s own vehicle and a desig-
nated 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-visi-
bility 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
appropriate or not. 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 situa-
tion.
Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a colli-
sion 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 appropri-
ately in order to ensure the safety of all involved.
To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON/OFF” button when not in use.
Situations unsuitable for dynamic 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
resulting in death or serious injury.
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 expressways
When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing