LEXUS RX450h 2016 Owners Manual

3214-5. Using the driving support systems
4
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.)

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

3234-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U In vehicle-to-vehicle distance control mode, the vehicle automatically acceler-
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. 3 2 6 )●
Constant speed control mode (  P. 3 3 1 )
Vehicle-to-vehicle distance button
Display
Set speed
Indicators
Cruise control switchDynamic radar cruise control 
 : If equippedSummary of functions 1
2
3
4
5

324 4-5. Using the driving support systems
RX450h_U_OM0E013U WA R N I N G ■
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 ca reful 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.
Even when the system is functioning normal ly, 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 safe ty 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 dr iver 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 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 off using the “ON/OFF” button when not in
use.

3254-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U WA R N I N G ■
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 result-
ing in death or serious injury. ●
Roads where there are pede strians, cyclers, 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 front surface of the radar sensor or camera sen-
sor ●
In traffic conditions that require frequent repeated acceleration and deceleration ●
When your vehicle is towing a trailer or during emergency towing ●
When an approach warning buzzer is heard often

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

3274-5. Using the driving support systems
4
Driving
RX450h_U_OM0E013U 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. 3 3 1 )
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 be comes the set speed.Setting the vehicle speed (vehicle-to-vehicle distance control mode) 1
2

328 4-5. Using the driving support systems
RX450h_U_OM0E013U To change the set speed, operate the lever until the desired set speed is dis-
played.
Increases the speed
Decreases the speed
Fine adjustment: Momentarily move
the lever in the desired direction.
Large adjustment: Hold the lever up or
down to change the speed, and release
when the desired speed is reached.
In the vehicle-to-vehicle distance control mode, the set speed will be increased
or decreased as follows: Fine adjustment: By 1 mph (1.6 km/h)
* 1
or 1 km/h (0.6 mph)
* 2
each time the lever is
operated
Large adjustment: Increases or decreases in 5 mph (8 km/h)
* 1
or 5 km/h (3.1 mph)
* 2
increments for as long as the lever is held
In the constant speed control mode (  P. 331), the set speed will be increased or
decreased as follows: Fine adjustment: By 1 mph (1.6 km/h)
* 1
or 1 km/h (0.6 mph)
* 2
each time the lever is
operated
Large adjustment: The speed will continue to change while the lever is held.
* 1
: When the set speed is shown in “MPH”
* 2
: When the set speed is shown in “km/h”Adjusting the set speed 1
2

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

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)