Lexus GS F 2019 Owner's Manuals

GS F_OM_OM30G90U_(U)
2414-5. Using the driving support systems
4
Driving
■Enabling/disabling the pre-collision system
The pre-collision system can be enabled/disabled on ( P. 100,
108) of the multi-information display.
The system is automatically enabled each time the engine switch is turned to IGNI-
TION ON mode.
If the system is disabled, the PCS
warning light will turn on and a mes-
sage will be displayed on the multi-
information display.
■Changing the pre-collision warning timing
The pre-collision warning timing can be changed on ( P. 100, 108)
of the multi-information display.
The operation timing setting is retained when the engine switch is turned off.
Far
The warning will begin to operate
earlier than with the default timing.
Middle
This is the default setting.
Near
The warning will begin to operate
later than with the default timing.
Changing settings of the pre-collision system
1
2
3

242
GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
■Operational conditions
The pre-collision system is enabled and the sy
stem determines that the possibility of a
frontal collision with a vehicle or pedestrian is high.
Each function is operationa l at the following speeds:
●Pre-collision warning:
• Vehicle speed is between approximately 7 and 110 mph (10 and 180 km/h). (For
detecting a pedestrian, vehicle speed is between approximately 7 and 50 mph [10
and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 7 mph (10 km/h) or more.
●Pre-collision brake assist:
• Vehicle speed is between approximately 20 and 110 mph (30 and 180 km/h). (For
detecting a pedestrian, vehicle speed is between approximately 20 and 50 mph
[30 and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is
approximately 20 mph (30 km/h) or more.
●Pre-collision braking:
• Vehicle speed is between approximately 7 and 110 mph (10 and 180 km/h). (Fordetecting a pedestrian, vehicle speed is between approximately 7 and 50 mph [10
and 80 km/h].)
• The relative speed between your vehicle and the vehicle or pedestrian ahead is approximately 7 mph (10 km/h) or more.
The system may not operate in the following situations:
●If a battery terminal has been disconnected and reconnected and then the vehicle has
not been driven for a certain amount of time
●If the shift lever is in R
●If VSC is disabled (only the pre-collis ion warning function will be operational)

GS F_OM_OM30G90U_(U)
2434-5. Using the driving support systems
4
Driving
■Pedestrian detection function
■Cancelation of the pre-collision braking
If either of the following occur while the pre-collision braking function is operating, it will
be canceled:
●The accelerator pedal is depressed strongly.
●The steering wheel is turned sharply or abruptly.
■Conditions under which the system may operate even if th ere is no possibility of a colli-
sion
●In some situations such as the following, th e system may determine that there is a possi-
bility of a frontal collision and operate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a preceding vehicle
• When overtaking a preceding vehicle that is changing lanes
The pre-collision system detects pedestrians
based on the size, prof
ile, and motion of a
detected object. However, a pedestrian may not
be detected depending on the surrounding
brightness and the motion, posture, and angle of
the detected object, preventing the system from
operating properly. ( P. 247)
• When overtaking a preceding vehicle that is making a left/right turn
• When passing a vehicle in an oncoming lane that is stopped to make a right/left turn

244
GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
• When rapidly closing on a vehicle ahead
• If the front of the vehicle is raised or lowered, such as when the road surface is uneven or undulating
• When approaching objects on the roadside, such as guardrails, utility poles, trees, or walls
• When driving on a narrow path surrounded by a structure, such as in a tunnel or on
an iron bridge
• When there is a metal object (manhole cover, steel plate, etc.), steps, or a protrusion
on the road surface or roadside
• When driving on a road where relative
location to vehicle ahead in an adjacent
lane may change, such as on a winding
road
• When there is a vehicle, pedestrian, or object by the roadside at the entrance of a
curve
• When a crossing pedestrian approaches very close to the vehicle
• When passing through a place with a low structure above the road (low ceiling, traffic
sign, etc.)

GS F_OM_OM30G90U_(U)
2454-5. Using the driving support systems
4
Driving
• When rapidly closing on an electric toll gate barrier, parking area barrier, or other
barrier that opens and closes
• When using an automatic car wash
• When the vehicle is hit by water, sn ow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When there are patterns or paint on the road or a wall that may be mistaken for a
vehicle or pedestrian
• When driving near an object that reflects radio waves, such as a large truck or
guardrail
• When driving near a TV tower, broadcasting station, electric power plant, or other location where strong radio waves or electrical noise may be present
• When passing under an object (billboard,
etc.) at the top of an uphill road
• When driving through or under objects that may contact the vehicle, such as thick
grass, tree branches, or a banner

246
GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
■Situations in which the system may not operate properly
●In some situations such as the following, a vehicle may not be detected by the radar
sensor and camera sensor, preventing
the system from operating properly:
• If an oncoming vehicle is approaching your vehicle
• If a vehicle ahead is a motorcycle or bicycle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a vehicle ahead is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shap ed, such as a tractor or side car
• If the sun or other light is shin ing directly on a vehicle ahead
• If a vehicle cuts in front of your ve hicle or emerges from beside a vehicle
• If a vehicle ahead makes an abrupt maneuver (such as sudden swerving, accelera-
tion or deceleration)
• When suddenly cutting behind a preceding vehicle
• When driving in inclement we ather such as heavy rain, fog, snow or a sandstorm
• When the vehicle is hit by water, sn ow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When driving in a place where the surrounding brightness changes suddenly, such as at the entrance or exit of a tunnel
• When a very bright light, such as the sun or the headlights of on coming traffic, shines
directly into the camera sensor
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in a tunnel
• If a preceding vehicle has a low rear end,
such as a low bed trailer
• If a vehicle ahead has extremely high ground clearance
• When a vehicle ahead is not directly in front of your vehicle

GS F_OM_OM30G90U_(U)
2474-5. Using the driving support systems
4
Driving
• After the engine has started the vehicle has not been driven for a certain amount oftime
• While making a left/right turn and for a few seconds after making a left/right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the wheels are misaligned
• If a wiper blade is blocking the camera sensor
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or ca mera sensor is misaligned
●In some situations such as the following, sufficient braking forc e may not be obtained,
preventing the system from performing properly:
• If the braking functions cannot operate to their full extent, such as when the brake parts are extremely cold, extremely hot, or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface
●Some pedestrians such as the following may not be detected by the radar sensor and
camera sensor, preventing the system from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or taller than approximately
6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a ra in coat, long skirt, etc.), making their sil-
houette obscure
• Pedestrians who are carrying large baggage, holding an umbrella, etc., hiding part
of their body
• Pedestrians who are bending forward or squatting
• Pedestrians who are pushing a stroller , wheelchair, bicycle or other vehicle
• Groups of pedestrians which are close together
• Pedestrians who are wearing white and look extremely bright
• Pedestrians in the dark, such as at night or while in a tunnel
• Pedestrians whose clothing appears to be nearly the same color or brightness as
their surroundings
• Pedestrians near walls, fences , guardrails, or large objects
• Pedestrians who are on a metal object (manhole cover, steel plate, etc.) on the road
• Pedestrians who are walking fast
• Pedestrians who are changing speed abruptly
• Pedestrians running out from be hind a vehicle or a large object
• Pedestrians who are extremely close to the side of the vehicle (outside rear view mirror, etc.)
• If the front of the vehicle is raised or low-
ered

248
GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
■If the PCS warning light flas
hes or illuminates and a warning message is displayed on
the multi-inform ation display
The pre-collision system may be temporarily unavailable or there may be a malfunction
in the system.
●In the following situations, the warning light will turn off, the message will disappear and
the system will become operational when normal operating conditions return:
• When the radar sensor or ca mera sensor or the area around either sensor is hot,
such as in the sun
• When the radar sensor or camera sensor or the area around either sensor is cold,
such as in an extremely cold environment
• When a front sensor is dirt y or covered with snow, etc.
• When the part of the windshield in front of the camera sensor is fogged up or cov-
ered with condensation or ice (Defogging the windshield: P. 316)
• If the camera sensor is obstructed, such as when the hood is open or a sticker is attached to the windshield near the camera sensor
●If the PCS warning light continues to flash or remains illuminated or the warning mes-
sage does not disappear even though the vehicle has returned to normal, the system
may be malfunctioning. Have the vehicle in spected by your Lexus dealer immediately.
■If VSC is disabled
●If VSC is disabled (P. 292), the pre-collision brake assist and pre-collision braking
functions are also disabled.
●The PCS warning light will turn on and “V SC Turned Off Pre-Collision Brake System
Unavailable” will be displayed on the multi-information display.

249
GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
4
Driving
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

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GS F_OM_OM30G90U_(U)4-5. Using the driving support systems
◆Steering assist function
When the system determines that
the vehicle might depart from its
lane, the system provides assistance
as necessary by operating the steer-
ing wheel in small amounts for a
short period of time to keep the
vehicle in its lane.
GS350/GS300: 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 dis-
played on the multi-information dis-
play and the warning buzzer sounds.
GS F: If the system detects that the
steering wheel has not been oper-
ated 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
function is temporarily canceled.
◆Vehicle sway warning function
When the vehicle is swaying or
appears as if it may depart from its
lane multiple times, the warning
buzzer sounds and a message is dis-
played on the multi-information dis-
play to alert the driver.