2018 Lexus GS450h cruise control

GS450h_OM_OM30G62U_(U)
1934-2. Driving procedures
4
Driving
■Automatic deactivation of shift range selection in the D position
Shift range selection in the D position will be deactivated in the following situations:
●When the vehicle comes to a stop
●If the accelerator pedal is depressed fo r more than a certain period of time
●When the shift lever is shifted to other than D
■Downshifting restrictions warning buzzer
To help ensure safety and driving performance, downshifti ng operation may sometimes
be restricted. In some circum stances, downshifting may not be possible even when the
shift lever or paddle shif t switch is operated. (A buzzer will sound twice.)
■Snow mode automatic deactivation
Snow mode is automatically deactivated if th e power switch is turned off after driving in
snow mode.
■When driving with cruise control or dynamic radar cruise control with full-speed range
activated
Even when performing the following actions with the intent of enabling engine braking,
engine braking will not activate because crui se control, dynamic radar cruise control or
dynamic radar cruise control with full-speed range will not be canceled.
●While driving in the D position or S mode, downshifting to 7, 6, 5 or 4. ( →P. 243, 255)
●When switching the driving mode to spor t mode while driving in D position. (→P. 258)
■Restraining sudden start (Drive-Start Control)
●When the following unusual operation is pe rformed, the hybrid system output may be
restrained.
• When the shift lever is shifted from R to D, D to R, N to R, P to D, or P to R (D
includes S) with the acce lerator pedal depressed, a warning message appears on
the multi-information display. ( →P. 410)
• When the accelerator pedal is depressed t oo much while the vehicle is in reverse.
■Shift lock system
The shift lock system is a system to prevent ac cidental operation of the shift lever in start-
ing.
The shift lever can be shifted from P only wh en the power switch is in ON mode and the
brake pedal is being depressed.
■If the shift lever cannot be shifted from P
First, check whether the brak e pedal is being depressed.
If the shift lever cannot be shifted with your foot on the brake pedal, there may be a prob-
lem with the shift lock system. Have the vehi cle inspected by your Lexus dealer immedi-
ately.
The following steps may be used as an emergency measure to ensure that the shift lever
can be shifted.
Releasing the shift lock:
Press the parking brake switch to chec k that the parking brake is set. (→P. 196)
Parking brake indicator will come on.
Turn the power switch to off.
Depress the brake pedal.
1
2
3

217
GS450h_OM_OM30G62U_(U)4-5. Using the driving support systems
4
Driving
Lexus Safety System+∗
◆PCS (Pre-Collision System)
→ P. 223
◆LKA (Lane-Keeping Assist)
→P. 234
◆Automatic High Beam
→P. 203
◆Dynamic radar cruise contro l with full-speed range
→ P. 243
∗: If equipped
The Lexus Safety System+ consists of the following drive assist systems and
contributes to a safe and comfo rtable driving experience:
WARNING
■Lexus Safety System+
The Lexus Safety System+ is designed to operate under the assumption that the driver
will drive safely, and is designed to help reduce the impact to the occupants and the
vehicle in the case of a collision or assist the driver in normal driving conditions.
As there is a limit to the degree of reco gnition accuracy and control performance that
this system can provide, do not overly rely on this system. The driver is always responsi-
ble for paying attention to the vehicle’s surroundings and driving safely.

234
GS450h_OM_OM30G62U_(U)
4-5. Using the driving support systems
LKA (Lane-Keeping Assist)∗
When driving on highways and freeways with white or yellow lines, this function
alerts the driver when the vehicle might depart from its lane and provides assis-
tance by operating the steering wheel to keep the vehicle in its lane. Further-
more, the system also provides steering assistance when dynamic radar cruise
control with full-speed range is operat ing to keep the vehicle in its lane.
The LKA system recognizes visible
white or yellow lines with the camera
sensor on the upper portion of the front
windshield.
◆Lane departure alert function
When the system determines that
the vehicle might depart from its
lane, a warning is displayed on the
multi-information display, and either
the warning buzzer sounds
or the
steering wheel vibrates to alert the
driver.
When the warning buzzer sounds or
the steering wheel vibrates, check
the surrounding road situation and
carefully operate the steering wheel
to move the vehicle back to the cen-
ter of the lane.
∗: If equipped
Summary of functions
Functions included in LKA system

236
GS450h_OM_OM30G62U_(U)
4-5. Using the driving support systems
◆Lane centering function
This function is linked with radar
cruise control and provides the
required assistance by operating the
steering wheel to keep the vehicle in
its current lane.
When radar cruise control is not
operating, the lane centering func-
tion does not operate.
If the system detects that the steering
wheel has not been operated for a
fixed amount of time or the steering
wheel is not being firmly gripped, a
warning is displayed on the multi-
information display and the warning
buzzer sounds.
WARNING
■Before using LKA system
Do not rely solely upon the LKA system. The LKA system does not automatically drive
the vehicle or reduce the amount of attention that must be paid to the area in front of
the vehicle. The driver must always assume full responsibility for driving safely by pay-
ing careful attention to the surrounding cond itions and operating the steering wheel to
correct the path of the vehicle. Also, the driver must take adequate breaks when
fatigued, such as from driving for a long period of time.
Failure to perform appropriate driving operat ions and pay careful attention may lead to
an accident, resulting in death or serious injury.

240
GS450h_OM_OM30G62U_(U)
4-5. Using the driving support systems
●Vehicle sway warning function
This function operates when all of the following conditions are met.
• Setting for “Sway Warning” in of the multi-information display is set to “On”.
( → P. 95)
• Vehicle speed is approximatel y 32 mph (50 km/h) or more.
• Width of traffic lane is approx imately 9.8 ft. (3 m) or more.
• No system malfunctions are detected. ( →P. 242)
●Lane centering function
This function operates when all of the following conditions are met.
• LKA is turned on.
• Setting for “Steering Assist” and “Lane Center” in of the multi-information
display are set to “On”. ( →P. 95)
• System recognizes white (yellow) lines.
• Dynamic radar cruise control with full-speed range is operating.
• Width of traffic lane is approximately 8.2 to 13.5 ft. (2.5 to 4.1 m).
• Turn signal lever is not operated.
• Vehicle is driven on a straight road or around a gentle curve with a radius of more
than approximately 656 ft. (200 m).
• No system malfunctions are detected. ( →P. 242)
• Vehicle does not accele rate or decelerate by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for changing lanes.
• ABS, VSC, TRAC and PCS (Pre-Collision System) are not operating.
• TRAC or VSC is not turned off.
• Steering assist function is not operating.
■Temporary cancellation of functions
When operation conditions are no longer met, a function may be temporarily canceled.
However, when the operation conditions are met again, operat ion of the function is auto-
matically restored. ( →P. 239)
■Steering assist function/lane centering function
Depending on the vehicle speed, lane depart ure situation, road conditions, etc., the
driver may not feel the function is operating or the function may not operate at all.
■Lane departure alert function
The warning buzzer may be difficult to hear due to external noise, audio playback, etc.
Also, it may be difficult to f eel steering wheel vibrations due to the road conditions, etc.

243
GS450h_OM_OM30G62U_(U)4-5. Using the driving support systems
4
Driving
Dynamic radar cruise control with full-speed
range
∗
In vehicle-to-vehicle distance control mode, the vehicle automatically a\
cceler-
ates, decelerates and stops to match the speed changes of the preceding vehicle
even if the accelerator pedal is not depr essed. In constant speed control mode,
the vehicle runs at a fixed speed.
Use the dynamic radar cruise control with full-speed range on freeways and
highways.
●Vehicle-to-vehicle distance control mode ( →P. 246)
●Constant speed control mode ( →P. 251)
Vehicle-to-vehicle distance switch
Display
Set speed
Indicators
Cruise control switch
∗: If equipped
Summary of functions
1
2
3
4
5

244
GS450h_OM_OM30G62U_(U)
4-5. Using the driving support systems
WARNING
■Before using dynamic radar cruise control with full-speed range
Driving safely is the sole responsibility of th e driver. Do not rely solely on the system,
and drive safely by always paying careful attention to your surroundings.
The dynamic radar cruise cont rol with full-speed range provides driving assistance to
reduce the driver’s burden. However, there are limitations to the assistance provided.
Set the speed appropriately depending on the speed limit, traffic flow, road conditions,
weather conditions, etc. The driver is responsible for checking the set speed.
Even when the system is functioning normally, 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 safety 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 with full-speed range is only intended to help the
driver in determining the following distan ce between the driver’s own vehicle and a
designated vehicle traveling ahead. It is no t a mechanism that allows careless or inat-
tentive driving, and it is not a system that can assist the driver in low-visibility condi-
tions. It is still necessary for driver to pa y close attention to the vehicle’s surroundings.
●Assisting the driver to judge proper following distance
The dynamic radar cruise control with full-speed range determines whether the fol-
lowing distance between the driver’s own vehicle and a designated 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 control with full-speed range has limited capability to pre-
vent or avoid a collision with a vehicle trave ling 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 with full-speed range activation
Switch the dynamic radar cruise control wi th full-speed range off using the “ON/OFF”
button when not in use.

GS450h_OM_OM30G62U_(U)
2454-5. Using the driving support systems
4
Driving
WARNING
■Situations unsuitable for dynamic radar cruise control with full-speed range
Do not use dynamic radar cruise control with full-speed range 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, cyclists, 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 fron t surface of the radar sensor or camera sen-
sor
●In traffic conditions that require frequent repeated a cceleration and deceleration
●During emergency towing
●When an approach warning buzzer is heard often