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320 4-5. Using the driving support systems
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Dynamic radar cruise control with full-speed range 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 se lected by using the paddle shift.
(vehicles with paddle shift switches) ●
Vehicle speed is above approximately 30 mph (50 km/h). However, when a preceding
vehicle is detected, the dynamic radar cruise control with full-speed range can be set
even if the vehicle speed is at or below 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 below approximately 25 mph (40 km/h) when there are no
vehicles ahead. ●
The preceding vehicle leaves the lane when your vehicle is following at a vehicle speed
below approximately 25 mph (40 km/h). Otherwise, the sensor cannot properly
detect the vehicle. ●
VSC is activated. ●
TRAC is activated for a period of time. ●
When the VSC or TRAC system is turned off by pressing the VSC OFF switch. ●
The sensor cannot detect correctly because it is covered in some way. ●
Pre-collision braking is activated. ●
The parking brake is operated. ●
The vehicle is stopped by system control on a steep incline. ●
The following are detected when the vehicle has been stopped by system control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-
son, there may be a malfunction in the system. Contact your Lexus dealer.
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3214-5. Using the driving support systems
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Driving
RX450h_U_OM0E013U ■
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 approximately 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 by pressing the VSC OFF switch. ●
Pre-collision braking is activated.
If constant speed control mode is automatica lly canceled for any other reason, there may
be a malfunction in the system. Contact your Lexus dealer. ■
Warning messages and buzzers for dynamic ra dar cruise control with full-speed range
Warning messages and buzzers are used to indicate a system malfunction or to inform
the driver of the need for caution while driving. If a warning message is shown on the
multi-information display, read the message and follow the instructions.■
When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal
when deceleration of the system is insuff icient or operate the accelerator pedal when
acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the approach
warning ( P. 318) may not be activated.●
Vehicles that cut in suddenly ●
Vehicles traveling at low speeds ●
Vehicles that are not moving in the same lane ●
Vehicles with small rear ends (traile rs with no load on board, etc.)
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322 4-5. Using the driving support systems
RX450h_U_OM0E013U ●
Motorcycles traveling in the same lane ●
When water or snow thrown up by the surrounding vehicles hinders the detecting of
the sensor
■
Conditions under which the ve hicle-to-vehicle distance co ntrol mode may not function
correctly
In the case of the following conditions, op erate the brake pedal (or accelerator pedal,
depending on the situ ation) 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
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326 4-5. Using the driving support systems
RX450h_U_OM0E013U 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 th e 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 wa rning warns you when the system cannot
decelerate sufficiently to prevent your ve hicle 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
1
2
3
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3294-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U Pressing the button 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
power switch is turned to ON mode.
If a vehicle is running ahead of you, the preceding 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 accordance with vehicle speed.
Pulling the lever toward you cancels
the speed control. The speed setting 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 mark1
2
3
Vehicle-to-vehicle distance settings (vehicle-to-vehicle distance con-
trol mode) Distance options Vehicle-to-vehicle distance
Long Approximately 160 ft. (50 m)
Medium Approximately 130 ft. (40 m)
Short Approximately 100 ft. (30 m)
Canceling and resuming the speed control 1
2
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330 4-5. Using the driving support systems
RX450h_U_OM0E013U 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 may 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 cruise control speed was set ●
When depressing the accelerator pedalApproach warning (vehicle-to-vehicle distance control mode)
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Driving
RX450h_U_OM0E013U ■
When the sensor may not be correctly detecting the vehicle ahead
In the case of the following and depending on the conditions, operate the brake pedal
when deceleration of the system is insuff icient or operate the accelerator pedal when
acceleration is required.
As the sensor may not be able to correctly detect these types of vehicles, the approach
warning ( P. 330) may not be activated.●
Vehicles that cut in suddenly ●
Vehicles traveling at low speeds ●
Vehicles that are not moving in the same lane ●
Vehicles with small rear ends (traile rs with no load on board, etc.)
●
Motorcycles traveling in the same lane ●
When water or snow thrown up by the surrounding vehicles hinders the detecting of
the sensor ●
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
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334 4-5. Using the driving support systems
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Conditions under which the ve hicle-to-vehicle distance co ntrol mode may not function
correctly
In the case of the following conditions, op erate the brake pedal (or accelerator pedal,
depending on the situ ation) 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 the road curves or when the lanes are
narrow ●
When steering wheel operation or your posi-
tion in the lane is unstable