brake light LEXUS RC350 2015 User Guide

2344-5. Using the driving support systems
RC350/RCF_U (OM24636U)
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 400 ft. (120 m) ahead, determines the current vehicle-to-vehicle
following distance, and operates to main tain a suitable following distance from
the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long downhill
slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-
tance can also be set by operating the vehicle-to-vehicle distance control.
Example of deceleration cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically deceler-
ates your vehicle. When a greater reduction in vehicle speed is necessary, the system
applies the brakes (the stop lights will come on at this time). A warning tone warns you
when the system cannot decelera te sufficiently to prevent your vehicle from closing in
on the vehicle ahead.
Example of follow-up cruising
When following a preceding vehicle driving slower than the set speed
The system continues follow-up cruising wh ile adjusting for changes in the speed of
the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by the driver.
Example of acceleration
When there are no longer any preceding vehicles driving slower than the set
speed
The system accelerates until the set speed is reached. The system then returns to con-
stant speed cruising.
Driving in vehicle-to-vehicle distance control mode
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2614-5. Using the driving support systems
4
Driving
RC350/RCF_U (OM24636U)
■Sensor detection information
●RC350: The sensor’s detection areas are limited to the areas around the vehicle’s front
and rear bumpers.
●RC F: The sensor’s detection areas are limited to the areas around the vehicle’s front
corner and rear bumpers.
●Certain vehicle conditions and the surround ing environment may affect the ability of
the sensor to correctly detect obstacles. Particular instances where this may occur are
listed below.
• There is dirt, snow or ice on the sensor . (Wiping the sensors will resolve this prob-
lem.)
• The sensor is frozen. (Thawing th e area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an abnormal
display, or obstacles may not be detected.
• The sensor is covered in any way.
• The vehicle is leaning co nsiderably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle engines, air brakes of large vehicles, or other loud noises producing ultrasonic waves.
• There is another vehicle equipped with parking assist sensor in the vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Lexus suspension (low ered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of their shape,
signs and other objects may be judged by the sensor to be closer than they are.
●The shape of the obstacle may prevent the sensor from detecting it. Pay particular
attention to the following obstacles:
• Wires, fences, ropes, etc.
• Cotton, snow and other materials that absorb sound waves
• Sharply-angled objects
•Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your vehi-
cle
●The following situations may occur during use.
• Depending on the shape of the obstacle and other factors, the detection distance
may shorten, or detect ion may be impossible.
• Obstacles may not be detected if they are too close to the sensor.
• There will be a short delay between obst acle detection and display. Even at slow
speeds, there is a possibility that the obstacle will come within the sensor’s detection
areas before the display is shown and the warning beep sounds.
• Thin posts or objects lower than the sensor may not be detected when approached, even if they have been detected once.
• It might be difficult to hear beeps due to the volume of the audio system or air flow noise of the air conditioning system.

2824-5. Using the driving support systems
RC350/RCF_U (OM24636U)
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or turning on
slippery road surfaces
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Prevents the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the vehicle speed
and steering wheel movement
◆DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristics and responsiveness of the vehicle
by slightly adjusting the rear wheel angle of the vehicle in accordance with
steering wheel movement.
Driving assist systems
To help enhance driving safety and performance, the following systems oper-
ate automatically in response to various driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too
heavily when operating the vehicle.

2854-5. Using the driving support systems
4
Driving
RC350/RCF_U (OM24636U)
RC F
To turn the TRAC system off, quickly
press and release ( ).
The “TRAC OFF” indicator light will
come on.
Press ( ) again to turn the
system back on.
■Turning off both TRAC and VSC systems
RC350
To turn the TRAC and VSC systems off, pr ess and hold for more than 3 seconds
while the vehicle is stopped.
The VSC OFF indicator light will come on and the “TRAC OFF” will be shown on the
multi-information display.
*1
Press again to turn the systems back on.
RC F
To turn the TRAC and VSC systems off, press and hold ( ) for more
than 3 seconds.
The “TRAC OFF” indicator light and the VSC OFF indicator light will come on.
*2
Press ( ) again to turn the systems back on.
*1: On vehicles with PCS (Pre-Collision System), pre-collision brake assist, pre-collision
braking, and steering cont rol (performed through cooperative control of PCS and
LDH) (if equipped) will also be disabled. The pre-collision system warning light will
come on and a message will be displaye d on the multi-information display. (P. 2 9 0 )
*2: On vehicles with PCS (Pre-Collision System ), pre-collision brake assist and pre-colli-
sion braking will also be di sabled. The pre-collision system warning light will come on
and a message will be displayed on the multi-information display. ( P. 2 9 0 )

2864-5. Using the driving support systems
RC350/RCF_U (OM24636U)
■Expert mode (RC F)
When expert mode is selected, it is possible to drive in a more sporty manner than other
drive modes. Expert mode disables the TRAC and VSC systems but the engine and
brakes may be controlled depending on the vehicle behavior.
■When the message is displayed on the mu lti-information display showing that TRAC
has been disabled even if has not been pressed (RC350)
TRAC and hill-start assist control cannot be operated. Contact your Lexus dealer.
■When the “TRAC OFF” indicator light comes on even if () has not been
pressed (RC F)
TRAC and hill-start assist control cannot be operated. Contact your Lexus dealer.
■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.
●When the steering wheel is operated for an extended period of time while the vehicle is
stopped or is moving very slowly
(on vehicles with LDH, DRS is disabled together with VGRS)
●When the steering wheel has been held fully to the left or right
The center position of the steering wheel may change when VGRS is disabled. However,
the position will return to normal after VGRS is reactivated.
■When the battery is disconnected (vehicles with VGRS)
The steering wheel may move fr om its straight forward position, but this will be corrected
automatically when driving. To select expert mode, press
()
when in SPORT S+ mode.
The “EXPERT” indicator will come on together
with the TRAC OFF and VSC OFF indicators.
To cancel expert mode, press
()
or use the driving mode se lect switch to select a
driving mode other than SPORT S+ mode.

2874-5. Using the driving support systems
4
Driving
RC350/RCF_U (OM24636U)
■Sounds and vibrations caused by the ABS, brake assist, VSC, 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 sys-
tems.
●Any of the following condit ions may occur when the above systems are operating.
None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slig htly after the ABS is activated.
• The brake pedal may move down s lightly after the ABS is activated.
■EPS, VGRS and DRS operation sound
When the steering wheel is operated, a motor sound may be heard. This does not indi-
cate a malfunction.
■Reactivation of the TRAC/VSC systems
Even after the TRAC/VSC systems have been turned off, turning the engine off and then
on again will automatically reactivate the TRAC/VSC systems.
■Reactivation of the TRAC system linked to vehicle speed
When only the TRAC system is turned off, the TRAC system will turn on when vehicle
speed increases. However, when both TRAC /VSC systems are turned off, the systems
will not turn on even when vehicle speed increases.
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The steering
wheel may feel heavy as a result. Should this occur, refrain from excessive steering input
or stop the vehicle and turn the engine of f. The EPS system should return to normal
within 10 minutes.
■Operating conditions of hill-start assist control
When the following four conditions are met, the hill-start assist control will operate:
●The shift lever is in a position other than P or N (when starting off forward/backward on
an upward incline).
●The vehicle is stopped.
●The accelerator pedal is not depressed.
●The parking brake is not engaged.
■Automatic system cancelation of hill-start assist control
The hill-start assist control will turn off in any of the following situations:
●The shift lever is moved to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.

2884-5. Using the driving support systems
RC350/RCF_U (OM24636U)
WA R N I N G
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as excessively
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 operat ing may exceed that of normal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always maintain 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 may not operate effectively when
Directional control and power may not be achievable while drivin g on slippery road
surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
●Do not overly rely on hill-start assist contro l. 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 con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.

2904-5. Using the driving support systems
RC350/RCF_U (OM24636U)
◆ Pre-collision warning
When a high possibility of a frontal
collision is detected, the pre-colli-
sion system warning light flashes, a
buzzer sounds and a message is
shown on the multi-information dis-
play to urge the driver to take eva-
sive action.
◆Pre-collision brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to ho w strongly the brake pedal is depressed.
The system may not warn the driver using a warning light, warning display and
buzzer when the system detects and judges braking operations.
◆Pre-collision braking
When there is a high possibility of a frontal collision, the system warns the
driver using a warning light, warning di splay and buzzer. If the system deter-
mines that a collision is unavoidable, the brakes are automatically applied to
reduce the collision speed.
◆Suspension control (if equipped)
When the system determines that there is a high possibility of a frontal colli-
sion, the operation of Adaptive Variable Suspension System ( P. 2 8 3 ) o p t i -
mally controls the damping force of the shock absorber.
PCS (Pre-Collision System)

: If equipped
When the radar sensor detects the possibility of a frontal collision, brakes are
automatically engaged to lessen im pact as well as vehicle damage.
The pre-collision system can be turned on and off as necessary by operating
the switch. ( P. 2 9 1 )

2934-5. Using the driving support systems
4
Driving
RC350/RCF_U (OM24636U)
■Conditions that may trigger the system even if there is no danger of a collision
In the following situations, the front of the sensor may be obstructed causing the system
to determine that there is a poss ibility of a collision and operate:
●When passing an oncoming vehicle on a cu rb or while making a left or right turn
●When rapidly closing on an obstruction in front of the vehicle, such as a vehicle or toll
gate
●When climbing a hill, and an overhead structure (billboard, low ceiling, street lamps,
etc.) appears in the vehicle’s line of travel
●When driving through a narrow passage or a place with a low ceiling (bridges, tunnels,
overhead passes, etc.)
●When driving on an uneven road surface
●When there is a metal object on the road surf ace, or a gap or protrusion in the road sur-
face
●When there is an extreme change in the vehicle height
●When the sensor is misaligned due to a stro ng impact to the surrounding area of the
sensor
●When there is an object on the side of the road at the entrance to a curve, such as
guardrails
●When the front of your vehicle is inclined (during emergency towing, carrying a heavy
load in the trunk, etc.)
When the system is activated in the situations described above, there is also a possibility
that the brakes will be applied with a force greater than normal.
■Obstacles not detected
The sensor cannot detect plasti c obstacles such as traffic cones. There may also be occa-
sions when the sensor cannot detect pedestrians, animals, bicycles, motorcycles, trees,
or snowdrifts.
■Situations in which the pre-collision system does not function properly
The system may not function effectively in situations such as the following:
●On roads with sharp bends or uneven surfaces
●If a vehicle suddenly moves in front of your vehicle, such as at an intersection
●If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
●In inclement weather such as heavy rain, fog, snow or sand storms
●If the vehicle is skidding when VSC is not operating
●When your vehicle is steeply inclined
●When the radar sensor moves off position due to its surrounding area being subjected
to a strong impact
●When an obstacle suddenly appears in front of the vehicle due to the steering wheel
being turned sharply or another cause
■Automatic cancelation of the pre-collision system
When a malfunction occurs due to sensor cont amination, etc. that results in the sensors
being unable to detect obstacles, the pre-collision syst em will be automatically disabled.
In this case, the system will not activate even if there is a collision possibility.
■When there is a malfunction in the system or if the system is temporarily unusable
The pre-collision system warning light will flash or illuminate and warning messages will
be displayed. ( P. 5 3 4 , 5 4 5 )

2954-5. Using the driving support systems
4
Driving
RC350/RCF_U (OM24636U)
WA R N I N G
■Limitations of the pre-collision system
●The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Never use the pre-collision safety system instead of normal braking operations. This
system is not designed to avoid or reduce collisions in every situation. Overly relying
on the system or entrusting it with safety may lead to an accident resulting in death or
serious injury.
Although this system is designed to suppor t in avoiding a collision or reducing the
damage of a collision, its effectiveness may change according to various conditions
(  P. 292, 293). Therefore, the system may not always provide the same perfor-
mance. Also, pre-collision braking function may not operate depending on the oper-
ations of the driver. If the driver is stepping on the brake pedal or is operating the
steering wheel, the system may determine th at the driver is taking evasive action and
pre-collision braking func tion may not operate.
●As the pre-collision system is designed to assi st the driver in safe driving, it may oper-
ate under sporty driving conditions, whic h may cause an accident. For this reason
under sporty driving conditions, it is reco mmended that this system be disabled by
using the PCS OFF switch.
■Handling the radar sensor
Observe the following to ensure the pre-collision system can function effectively.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surr ounding area to a strong impact.
If the sensor moves even slightly off posi tion, the system may become inaccurate or
malfunction. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by your Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding area.
●Do not modify or paint the sensor and grille cover.
●If the radar sensor needs to be replaced, contact your Lexus dealer.