
1614-5. Using the driving support systems
RC350/RC300 Owner's Manual
4
Driving
and rear wheels and effort necessary
to turn the steering wheel to help
enhance steering responsiveness.
WARNING
■Limitations of the pre-collision system
●The driver is solely responsible for safe
driving. Always drive safely, taking
care to observe your surroundings.
Do not use the pre-collision system
instead of normal braking operations
under any circumstances. This system
will not prevent collisions or lessen col-
lision damage or injury in every situa-
tion. Do not overly rely on this system.
Failure to do so may lead to an acci-
dent, resulting in death or serious
injury.
●Although this system is designed to
help avoid a collision or help reduce
the impact of the collision, its effective-
ness may change according to various
conditions, therefore the system may
not always be able to achieve the same
level of performance.
Read the following conditions care-
fully. Do not overly rely on this system
and always drive carefully.
• Conditions under which the system may operate even if there is no possi-
bility of a collision:
P.163
• Conditions under which the system may not operate properly:
P.165
●Do not attempt to test the operation of
the pre-collision system yourself.
Depending on the objects used for
testing (dummies, cardboard objects
imitating detectable objects, etc.), the
system may not operate properly, pos-
sibly leading to an accident.
■Pre-collision braking
●When the pre-collision braking func-
tion is operating, a large amount of
braking force will be applied.
●If the vehicle is st opped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seco nds. Depress the
brake pedal as necessary.
●The pre-collision braking function may
not operate if certain operations are
performed by the driver. If the acceler-
ator pedal is being depressed strongly
or the steering wheel is being turned,
the system may determine that the
driver is taking evasive action and pos-
sibly prevent the pre-collision braking
function from operating.
●In some situations, while the pre-colli-
sion braking function is operating,
operation of the function may be
canceled if the ac celerator pedal is
depressed strongly or the steering
wheel is turned and the system deter-
mines that the driver is taking evasive
action.
●If the brake pedal is being depressed,
the system may determine that the
driver is taking evasive action and pos-
sibly delay the operat ion timing of the
pre-collision braking function.
■When to disable the pre-collision sys-
tem
In the following situations, disable the
system, as it may not operate properly,
possibly leading to an accident resulting
in death or serious injury:
●When the vehicle is being towed
●When your vehicle is towing another
vehicle
●When transporting the vehicle via
truck, boat, train or similar means of
transportation
●When the vehicle is raised on a lift with
the engine running and the tires are
allowed to rotate freely

1624-5. Using the driving support systems
RC350/RC300 Owner's Manual
■Enabling/disabling the pre-colli-
sion system
The pre-collision system can be
enabled/disabled on ( P.71) 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 warn-
ing light will turn on and a message will
be displayed on the multi-information
display.
■Changing the pre-collision warn-
ing timing
The pre-collision warning timing can
be changed on ( P.71) of the
multi-information display.
The operation timing setting is retained
when the engine switch is turned off.
1 Far
The warning will begin to operate earlier
than with the default timing.
2Middle
This is the default setting.
3Near
WARNING
●When inspecting the vehicle using a
drum tester such as a chassis dyna-
mometer or speedometer tester, or
when using an on vehicle wheel bal-
ancer
●When a strong impact is applied to the
front bumper or front grille, due to an
accident or other reasons
●If the vehicle cannot be driven in a sta-
ble manner, such as when the vehicle
has been in an accident or is malfunc-
tioning
●When the vehicle is driven in a sporty
manner or off-road
●When the tires are not properly
inflated
●When the tires are very worn
●When tires of a size other than speci-
fied are installed
●When tire chains are installed
●When a compact spare tire or an
emergency tire puncture repair kit is
used
●If equipment (snow plow, etc.) that may
obstruct the radar sensor or front cam-
era is temporarily installed to the vehi-
cle
Changing settings of the pre-col-
lision system

1664-5. Using the driving support systems
RC350/RC300 Owner's Manual
• The vehicle is wobbling.
• The vehicle is being driven at extremely high speeds.
• When driving on a hill
• If the radar sensor or front camera is mis- aligned
●In some situations such as the following,
sufficient braking force 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 front camera, preventing the system
from operating properly:
• Pedestrians shorter than approximately 3.2 ft. (1 m) or tall er than approximately
6.5 ft. (2 m)
• Pedestrians wearing oversized clothing (a rain coat, long skir t, etc.), making their
silhouette obscure
• Pedestrians who are carrying large bag- gage, 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 co lor 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 behind a
vehicle or a large object
• Pedestrians who are extremely close to
the side of the vehicle (outside rear view
mirror, etc.)
■If VSC is disabled
●If VSC is disabled ( P.198), the pre-col-
lision brake assist and pre-collision brak-
ing functions are also disabled.
●The PCS warning light will turn on and
“VSC Turned Off Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.

1684-5. Using the driving support systems
RC350/RC300 Owner's Manual
■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 displayed on
the multi-information display to alert
the driver.
WARNING
■Before using LDA system
Do not rely solely upon the LDA system.
The LDA 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 driv-
ing safely by paying careful attention to
the surrounding conditions and operat-
ing 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
operations and pay careful attention may
lead to an accident, resulting in death or
serious injury.
■To avoid operating LDA system by
mistake
When not using the LDA system, use the
LDA switch to turn the system off.
■Situations unsuitable for LDA system
Do not use the LDA system in the follow-
ing situations.
The system may not operate properly
and lead to an accident, resulting in
death or serious injury.
●A spare tire, tire chains, etc. are
equipped.
●When the tires have been excessively
worn, or when the tire inflation pres-
sure is low.
●Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●Objects or patterns that could be mis-
taken for white (yellow) lines are pres-
ent on the side of the road (guardrails,
curbs, reflective poles, etc.).
●Vehicle is driven on a snow-covered
road.
●White (yellow) lines are difficult to see
due to rain, snow, fog, dust, etc.

1724-5. Using the driving support systems
RC350/RC300 Owner's Manual
●There are shadows on the road that run
parallel with, or cover, the white (yellow)
lines.
●The vehicle is driven in an area without
white (yellow) lines, such as in front of a
tollgate or checkpoint, or at an intersec-
tion, etc.
●The white (yellow) lines are cracked,
“Botts’ dots”, “Raise d pavement marker”
or stones are present.
●The white (yellow) lines cannot be seen
or are difficult to see due to sand, etc.
●The vehicle is driven on a road surface
that is wet due to rain, puddles, etc.
●The traffic lines are yellow (which may be
more difficult to recognize than lines that
are white).
●The white (yellow) lines cross over a curb,
etc.
●The vehicle is driven on a bright surface,
such as concrete.
●The vehicle is driven on a surface that is
bright due to reflected light, etc.
●The vehicle is driven in an area where the
brightness changes suddenly, such as at
the entrances and exits of tunnels, etc.
●Light from the headlights of an oncoming
vehicle, the sun, etc. enters the camera.
●The vehicle is driven where the road
diverges, merges, etc.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which tilts
left or right, or a winding road.
●The vehicle is driven on an unpaved or
rough road.
●The vehicle is driven around a sharp
curve.
●The traffic lane is excessively narrow or
wide.
●The vehicle is extremely tilted due to car-
rying heavy luggage or having improper
tire pressure.
●The distance to the preceding vehicle is
extremely short.
●The vehicle is moving up and down a
large amount due to road conditions
during driving (poor roads or road
seams).
●The headlight lenses are dirty and emit a
faint amount of light at night, or the beam
axis has deviated.
●The vehicle is struck by a crosswind.
●The vehicle has just changed lanes or
crossed an intersection.
●Snow tires, etc. are equipped.
■Warning message
If the following warning messag e is displayed on the multi-information display and the LDA
indicator illuminates in orange, follow th e appropriate troubleshooting procedure.
Warning messageDetails/Actions
“Lane Departure Alert Malfunction
Visit Your Dealer”The system may not be operating properly.
Have the vehicle inspected at your Lexus dealer.
“Front Camera Unavailable Remove
Debris On Windshield”
Dirt, rain, condensation, ice, snow, etc. are present
on the windshield in front of the camera sensor.
Turn the LDA system off, remove any dirt, rain,
condensation, ice, snow, et c. from the windshield,
and then turn the LDA system back on.

1934-5. Using the driving support systems
RC350/RC300 Owner's Manual
4
Driving
●Guardrails, walls, signs, parked vehicles
and similar stationary objects*
●Following vehicles that are in the same
lane*
●Vehicles traveling 2 lanes away from your
vehicle*
●Vehicles which are being overtaken rap-
idly by your vehicle*
*
: Depending on the conditions, detection of a vehicle and/or object may occur.
■Conditions under which the BSM func-
tion may not function correctly
●The BSM function may not detect vehi-
cles correctly in the following situations:
• When the sensor is misaligned due to a
strong impact to the sensor or its sur-
rounding area
• When mud, snow, ice, a sticker, etc. is
covering the sensor or surrounding area
on the rear bumper
• When driving on a road surface that is
wet with standing water during bad
weather, such as heav y rain, snow, or fog
• When multiple vehicles are approaching
with only a small gap between each vehi-
cle
• When the distance between your vehicle and a following vehicle is short
• When there is a significant difference in speed between your vehicle and the vehi-
cle that enters the detection area
• When the difference in speed between your vehicle and another vehicle is
changing
• When a vehicle enters a detection area traveling at about the same speed as your
vehicle
• As your vehicle starts from a stop, a vehi- cle remains in the detection area
• When driving up and down consecutive steep inclines, such as hills, dips in the
road, etc.
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When vehicle lanes are wide, or when driving on the edge of a lane, and the
vehicle in an adjacent lane is far away
from your vehicle
• When a bicycle carrier or other acces- sory is installed to the rear of the vehicle
• When there is a significant difference in height between your vehicle and the
vehicle that enters the detection area
• Immediately after the BSM main switch is
turned on
●Instances of the BSM function unneces-
sarily detecting a vehicle and/or object
may increase in the following situations:
• When the sensor is misaligned due to a strong impact to the sensor or its sur-
rounding area
• When the distance between your vehicle and a guardrail, wall, etc. that enters the
detection area is short
• When driving up and down consecutive steep inclines, such as hills, dips in the
road, etc.
• When vehicle lanes are narrow, or when driving on the edge of a lane, and a vehi-
cle traveling in a lane other than the adja-
cent lanes enters the detection area
• When driving on roads with sharp bends, consecutive curves, or uneven surfaces
• When the tires are slipping or spinning
• When the distance between your vehicle and a following vehicle is short
• When a bicycle carrier or other acces- sory is installed to the rear of the vehicle
■Operation of the RCTA function
The RCTA function uses radar sensors to detect vehicles approaching from the
right or left at the rear of the vehicle and alerts the driver of the presence of such
vehicles by flashing the outside rear view mirror indicators and sounding a buzzer.
RCTA function

2014-5. Using the driving support systems
RC350/RC300 Owner's Manual
4
Driving
ever, the position will return to normal after
VGRS is reactivated.
■When the battery is disconnected (vehi-
cles with VGRS)
The steering wheel may move from its
straight forward position, but this will be
corrected automatically when driving.
■Sounds and vibrations caused by the
ABS, brake assist, VS C, TRAC, hill-start
assist control and VGRS systems
●A sound may be heard from the engine
compartment when the brake pedal is
depressed repeatedly, when the engine is
started or just after the vehicle begins to
move. This sound does not indicate that a
malfunction has occurred in any of these
systems.
●Any of the following conditions may
occur when the above systems are oper-
ating. None of these indicates that a mal-
function has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard also after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after
the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
■EPS, VGRS and DR S operation sound
When the steering wheel is operated, a
motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■Automatic reactivation of TRAC/VSC
systems
After turning the TRAC and VSC systems
off, the systems w ill be automatically
re-enabled in the following situations:
●When the engine switch is turned off
●If only the TRAC system is turned off, the
TRAC will turn on when vehicle speed
increases
If both the TRAC and VSC systems are
turned off, automatic re-enabling will not
occur when vehicle speed increases.
■Reduced effectiveness of the EPS sys-
tem
The effectiveness of the EPS system is
reduced to prevent the system from over-
heating when there is frequent steering
input over an extended period of time. The
steering wheel may feel heavy as a result.
Should this occur, re frain from excessive
steering input or stop the vehicle and turn
the engine off. The EPS system should
return to normal within 10 minutes.
WARNING
■The ABS does not operate effectively
when
●The limits of tire gripping performance
have been exceeded (such as exces-
sively worn tires on a snow covered
road).
●The vehicle hydroplanes while driving
at high speed on wet or slick roads.
■Stopping distance when the ABS is
operating may exceed that of normal
conditions
The ABS is not designed to shorten the
vehicle’s stopping di stance. Always main-
tain a safe distance from the vehicle in
front of you, especially in the following
situations:
●When driving on dirt, gravel or
snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes
or uneven surfaces
■TRAC/VSC may not operate effec-
tively when
Directional control and power may not
be achievable while driving on slippery
road surfaces, even if the TRAC/VSC
system is operating. Drive the vehicle
carefully in conditions where stability and
power may be lost.

2024-5. Using the driving support systems
RC350/RC300 Owner's Manual
WARNING
■Hill-start assist control does not oper-
ate effectively when
●Do not overly rely on hill-start assist
control. Hill-start assist control may
not operate effectively on steep
inclines and roads covered with ice.
●Unlike the parking brake, hill-start
assist control is not intended to hold
the vehicle stationary for an extended
period of time. Do not attempt to use
hill-start assist control to hold the vehi-
cle on an incline, as doing so may lead
to an accident.
■When the TRAC/VSC is activated
The slip indicator light flashes. Always
drive carefully. Re ckless driving may
cause an accident. Exercise particular
care when the indicator light flashes.
■When the TRAC/VSC systems are
turned off
Be especially careful and drive at a speed
appropriate to the road conditions. As
these are the systems to help ensure
vehicle stability and driving force, do not
turn the TRAC/VSC systems off unless
necessary.
■Replacing tires
Make sure that all ti res are of the speci-
fied size, brand, tread pattern and total
load capacity. In addition, make sure that
the tires are inflated to the recom-
mended tire inflation pressure level.
The ABS, TRAC and VSC systems will
not function correctly if different tires are
installed on the vehicle.
Contact your Lexus dealer for further
information when replacing tires or
wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or
modifying the suspension will affect the
driving assist systems, and may cause a
system to malfunction.