Lexus GS450h 2015 Owner's Manual
Manufacturer: LEXUS, Model Year: 2015, Model line: GS450h, Model: Lexus GS450h 2015Pages: 654, PDF Size: 34.84 MB
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4-5. Using the driving support systems
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 maintain 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
distance can also be set by operating the vehicle-to-vehicle distance control.
Example of deceleration cruising and follow-up cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automatically decel-
erates your vehicle. When a greater reduction in vehicle speed is necessary, the
system applies the brakes. 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. A warning tone warns you when the system cannot decelerate sufficiently
to prevent your vehicle from closing in on the vehicle ahead. When the vehicle
ahead of you stops, your vehicle will also stop. After the vehicle ahead starts off,
pushing the cruise control lever up or depressing the accelerator pedal will
resume follow-up cruising.
Driving in vehicle-to-vehicle distance control mode
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2614-5. Using the driving support systems
4
Driving
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
constant speed cruising.
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic 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. Apply the brakes to ensure an appropriate vehicle-to-vehicle dis-
tance.
■Warnings may not occur when
In the following instances, there is a possibility that the warnings will not
occur:
●When the speed of the vehicle ahead matches or exceeds your vehi-
cle speed
●When the vehicle ahead is traveling at an extremely slow speed or is
stationary
●Immediately after the cruise control speed was set
●At the instant the accelerator is applied
Ap proach warni ng
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4-5. Using the driving support systems
When constant speed control mode is selected, your vehicle will maintain
a set speed without controlling the vehicle-to-vehicle distance. Select this
mode only when vehicle-to-vehicle distance control mode does not func-
tion correctly due to dirt etc.
Press the “ON/OFF” button to
activate 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 1 second.)
Cruise control indicator will come on.
When in constant speed control
mode, to return to vehicle-to-vehicle
distance control mode, push the lever
forward again and hold for approxi-
mately 1 second.
After the desired speed has been set,
it is not possible to return to vehicle-
to-vehicle distance control mode.
If the power switch is turned off and
then turned to ON mode again, the
vehicle will automatically return to
vehicle-to-vehicle distance control
mode.
Adjusting the speed setting: →P. 2 5 6
Canceling and resuming the speed
setting: →P. 2 5 9
Selecting conventional constant speed control mode
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2634-5. Using the driving support systems
4
Driving
■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 selected by using the paddle shift.
●Vehicle speed is above approximately 30 mph (50 km/h).
■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 following
situations:
●Actual vehicle speed falls below approximately 25 mph (40 km/h) when there are
no vehicle ahead.
●The preceding vehicle leaves the lane when your vehicle is following at a speed
below 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.
●The sensor cannot operate correctly because it is covered in some way.
●The windshield wipers are operating at high speed (when the wiper switch is set to
AUTO mode or the high speed wiper operation).
●When snow mode is set.
●The parking brake is operated.
●The vehicle is stopped by system control on a steep incline.
●Pre-collision brake assist is activated.
●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 trunk or hood is opened.
• The vehicle has been stopped for about 3 minutes.
If vehicle-to-vehicle distance control driving is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.
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4-5. Using the driving support systems
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situations:
●Actual vehicle speed is more than approximately 10 mph (16 km/h) below the set
vehicle speed.
At this time, the memorized set speed is not retained.
●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.
■When the LKA (Lane-Keeping Assist) will be activated
Using the radar cruise control in vehicle-to-vehicle distance control mode, lane
keeping assist function is activated.
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle
distance control operates properly. (Some obstructions, such as snow, ice or plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control with full-speed range is canceled if an obstruction is
detected.
■Warning messages and buzzers for dynamic radar 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. (→P. 5 1 6 )
Grille cover
Radar sensor
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