2015 Lexus GS300h warning

3134-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
■Automatic cancelation of constant speed control mode
Constant speed control mode is automatically canceled in the following situations:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below the set vehi-
cle speed.
●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.
●Pre-crash braking is activated.
If constant speed control mode 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.
■Warning messages and buzzers for dynamic radar cruise control with full-speed range
Warning messages and buzzers are used to in dicate a system malfunction or to inform
the driver of the need for caution while driv ing. If a warning message is shown on the
multi-information display, read the message and follow the instructions. ( →P. 4 8 2 )
■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 insufficient 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. 310) 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

3174-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
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 pedestrians, cyclists, etc.
●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 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

3224-5. Using the driving support systems
GS450h_300h_OM_OM30F00E_(EE)
Pulling the lever toward you cancels
the speed control.
The speed control 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 40 km/h (25 mph) or
less.
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.
■Wa r n i n g s m a y n o t o c c u r w h e n
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 pedal
Canceling and resuming the speed control
1
2
Approach warning (vehicle-to-vehicle distance control mode)

3244-5. Using the driving support systems
GS450h_300h_OM_OM30F00E_(EE)
■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 switch.
●Vehicle speed is above approximately 50 km/h (30 mph).
■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 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.
●When snow mode is set.
●The sensor cannot detect correctly because it is covered in some way.
●Pre-crash braking is activated.
If vehicle-to-vehicle distance control mode is automatically canceled for any other rea-
son, 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 mode
Constant speed control mode is automatica lly canceled in the following situations:
●Actual vehicle speed is more than approximately 16 km/h (10 mph) below the set vehi-
cle speed.
●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.
●Pre-crash braking is activated.
If constant speed control mode 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.
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to in dicate a system malfunction or to inform
the driver of the need for caution while driv ing. If a warning message is shown on the
multi-information display, read the message and follow the instructions. ( →P. 4 8 2 )

3254-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
■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 insufficient 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. 322) 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

3294-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicle speed in any of the following situations.
●Actual vehicle speed falls more than approximately 16 km/h (10 mph) below the preset
vehicle speed.
At this time, the memorized set speed is not retained.
●Actual vehicle speed is 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.
■If the warning message for the cruise control is shown on the multi-information display
Press the “ON/OFF” button once to deactivate the system, and then press the button
again to reactivate the system.
If the cruise control speed cannot be set or if the cruise control cancels immediately after
being activated, there may be a malfunction in the cruise control system. Have the vehi-
cle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
WA R N I N G
■To avoid operating the cruise control by mistake
Switch the cruise control off using the “ON/OFF” button when not in use.
■Situations unsuitable for cruise control
Do not use cruise control in any of the following situations.
Doing so may result in loss of 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 hills
Vehicle speed may exceed the set sp eed when driving down a steep hill.
●When your vehicle is towing a trailer or during emergency towing

3344-5. Using the driving support systems
GS450h_300h_OM_OM30F00E_(EE)
■The outside rear view mirror indicators visibility
When under strong sunlight, the outside rear view mirror indicator may be difficult to
see.
■Rear Crossing Traffic Alert buzzer hearing
Rear Crossing Traffic Alert function may be difficult to hear over loud noises such as high
audio volume.
■When there is a malfunction in the Blind Spot Monitor
If a system malfunction is detected due to any of the following reasons, warning mes-
sages will be displayed: ( →P. 4 8 2 )
●There is a malfunction with the sensors
●The sensors have become dirty
●The outside temperature is extremely high or low
●The sensor voltage has become abnormal
■Switching the Blind Spot Monitor function and Rear Crossing Traffic Alert function on
and off
Settings can be changed from on the multi-information display (→P. 111).
Press or on the meter control switch and select “BSM”.
Each time on the meter control switch is pressed, the function switches between
“On” and “Off”.
■Certification for the Blind Spot Monitor
1
2

3474-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
■Turning off both TRC and VSC systems
To turn the TRC and VSC systems off, press and hold for more than 3 seconds while
the vehicle is stopped.
The VSC OFF indicator light will come on an d the “Traction Control Turned Off” will
be shown on the multi-information display.
*
Press again to turn the systems back on.
*: On vehicles with PCS (Pre-Crash Safety system), pre-crash brake assist and pre-
crash braking will also be disabled. The PCS (Pre-Crash Safety system) warning
light will come on and a message will be di splayed on the multi-information display.
( → P. 4 8 2 )
■When the message is displayed on the mult i-information display showing that TRC has
been disabled even if has not been pressed
TRC and hill-start assist control cannot be operated. Contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional.
■VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move fr om its straight forward position, but it will
return when the system restarts.
●The steering wheel is operated for an extended period of time while the vehicle is
stopped or is moving very slowly.
●When force is continuously applied for a long time with the steering wheel turned as far
as it will go.
The center position of the steering wheel may change when VGRS is disabled. How-
ever, the position will return to normal after VGRS is reactivated.
■When the 12-volt battery is disconnected
The steering wheel may move from its straight forward position, but this will be corrected
automatically when driving.