2017 Lexus GS300h warning

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GS450h_300h_OM_OM30F92E_(EE)
RSA (Road Sign Assist)
RSA recognizes specific road signs
using the camera sensor and provides
information to the driver via the multi-
information display.
If the system judges that the vehicle is being driven over the speed limit, perform-
ing prohibited actions, etc. in relation to the recogniz
ed road signs, it alerts the
driver using a warning display and warning buzzer *
.
* : This setting needs to be customized.
: If equipped
Summary of function
Camera sensor
WARNING
■Before using the RSA
Do not rely solely upon the RSA system. RS A is a system which supports the driver by
providing information, but it is not a replacement for a driver’s own vision and aware-
ness. Drive safely by always paying careful attention to the traffic rules.
Inappropriate or negligent driving could lead to an unexpected accident.

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GS450h_300h_OM_OM30F92E_(EE) *
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: If the turn signal indicator is not operated when changing lanes, the mark does not dis-
play.
* 2
:On some models
In the following situations, the RSA system alerts the driver using a warning dis-
play. ● When the vehicle speed exceeds the speed warning threshold applied to the
speed limit of the sign displayed on the multi-information display, the sign
color becomes inverted.
● If it is detected that your vehicle is overtaking when a no overtaking sign is dis-
played on the multi-information display, the sign flashes.
● On some models: When the RSA system recognizes a no-entry sign and
detects that the vehicle has entered a no-entry area based on the map infor-
mation of the navigation system, the no-entry sign flashes.
Depending on the situation, traffic environment (traffic direction, speed , unit)
may be detected incorrectly and a warning display may not operate properly.
■Automatic turn-off of RSA sign display
One or more signs automatically turn off in the following situations.
●A new sign is not recognized for a certain distance.
●The road changes due to a left or right turn, etc.
■Conditions in which the function may not operate or detect correctly
In the following situations, RSA does not op erate normally and may not recognize signs,
display the incorrect sign, etc. However, this does not indicate a malfunction.
●The camera sensor is misaligned due to a st rong impact being applied to the sensor,
etc.
●Dirt, snow, stickers, etc. are on the windshield near the camera sensor.
●In inclement weather such as heavy rain, fog, snow or sand storms
●Light from an oncoming vehicle, the sun, etc. enters the camera sensor.
●The sign is dirty, faded, tilted or bent, and if an electronic sign, the contrast is poor.
●All or part of the sign is hidden by the leaves of a tree, a pole, etc.
●The sign is only visible to the camera sensor for a short amount of time.
●The driving scene (turning, lane change, etc.) is judged incorrectly.
●Even if it is a sign not appropriate for the currently traveled lane, such a sign exists
directly after a freeway branches, or in an adjacent lane just before merging.
●Stickers are attached to the rear of the preceding vehicle.
●A sign resembling a system compatible sign is recognized.
●The vehicle is driven in a country with a different direction of traffic.
Warning display

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GS450h_300h_OM_OM30F92E_(EE)
●Side road speed signs may be detected and di splayed (if positioned in sight of the cam-
era sensor) while the vehicle is traveling on the main road.
●Roundabout exit road speed signs may be detected and displayed (if positioned in sight
of the camera sensor) while traveling on a roundabout.
●On some models: The speed information displayed on the meter and t hat displayed on
the navigation system may be different due to the navigation system using map data.
■When driving vehicle in country with different speed unit
Since RSA recognizes signs based on the set un it of the meter, it is necessary to change
the set unit of the meter. Adjust the set unit of the meter to the speed unit of signs in the
current location. ( P. 565)
■Turning the system on/off
■Speed limit sign display
If the power switch was last turned off while a speed limit sign was displayed on the multi-
information display, the same sign displays again when the power switch is turned to ON
mode.
■Customization
Setting (e.g. speeding warning threshold) can be changed.
(Customizable feature: P. 561)
Select on of the
multi-information display (
P. 111)
Press on the steering wheel.
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WARNING
■Before using dynamic radar cruise control with full-speed range
Driving safely is the sole resp onsibility of the driver. Do not rely solely on the system,
and drive safely by always paying careful attention to your surroundings.
The dynamic radar cruise control with full-speed range provides driving assistance to
reduce the driver’s burden. However, there are limitations to the assistance provided.
Even when the system is functioning norma lly, 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, resulting 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-sp eed range is only intended to help the
driver in determining the fo llowing distance 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 pay 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.

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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 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 sp eed when driving down a steep hill.
●At entrances to freeways and highways
●When weather conditions are bad enough that they may prevent the se nsors 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 acceleration and deceleration
●When your vehicle is towing a trailer (vehicles with towing package) or during emer-
gency towing
●When an approach warning buzzer is heard often

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GS450h_300h_OM_OM30F92E_(EE) Pulling the lever toward you cancels
the speed control.
The speed control is also canceled when
the brake pedal is depressed.
(When the vehicle has been stopped by
system control, depressing the brake
pedal does not cancel the setting.)
Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.
However, when a vehicle ahead is not detected, 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.
■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 pedal
Canceling and resuming the speed control
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Approach warning (vehicle-to- vehicle distance control mode)

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■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 an y authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
■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 driv ing. If a warning message is shown on the
multi-information display, read the message and follow the instructions. ( P. 466)
■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. 303) 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 (trailers with no load on board, etc.)
●Motorcycles travelin g in the same lane
●When water or snow thrown up by the surrounding vehicles hinders the detecting of
the sensor

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■Automatic cruise control cancelation
Cruise control will stop maintaining the vehicl e 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 retaile r or Lexus authorized repairer, or any reli-
able repairer.
WARNING
■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