brakes LEXUS LS500 2021 User Guide
[x] Cancel search | Manufacturer: LEXUS, Model Year: 2021, Model line: LS500, Model: LEXUS LS500 2021Pages: 520, PDF Size: 9.81 MB
Page 228 of 520

2284-5. Using the driving support systems
sage will be displayed on the
multi-information display to urge the
driver to take evasive action.
■Pre-collision brake assist
When the system determines that the
possibility of a frontal collision is high,
the system applies greater braking
force in relation to how strongly the
brake pedal is depressed.
■Pre-collision braking
If the system determines that the possi-
bility of a frontal collision is extremely
high, the brakes are automatically
applied to help avoid the collision or
reduce the impact of the collision.
■Pre-collision seatbacks (front pas-
senger’s seat / power rear seat [if
equipped])
If the system determines that the possi-
bility of a frontal collision is high, it may
move the seatbacks of the front pas-
senger’s seat and power rear seats to
the upright position automatically, if
reclined.
If a seat is being ad justed, it may not be
moved by the pre-collision seat function.
■Suspension control
When the system determines that the
possibility of a frontal collision is high, the Adaptive Variable Suspension Sys-
tem (
P.304) will control the damp-
ing force of the shock absorbers to
help maintain an appropriate vehicle
posture.
■Steering control
When the system determines that the
possibility of a frontal collision is high
and the driver is op erating the steering
wheel, the LDH system ( P.305) will
control the turning angle of the front
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.231
• Conditions under which the system may not operate properly: P.233
Page 234 of 520

2344-5. Using the driving support systems
as heavy rain, fog, snow or a sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in
a tunnel, making a detectable object
appear to be nearly the same color as its
surroundings
• When driving in a place where the sur- rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• After the engine has started the vehicle has not been driven for a certain amount
of time
• While making a left/right turn and for a few seconds after makin g 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 front of the vehicle is raised or low-
ered
• If the wheels are misaligned
• If a wiper blade is blocking the front cam- era
• 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
■If VSC is disabled
●If VSC is disabled ( P.306), the pre-collision brake assist and pre-colli-
sion braking 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.
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2574-5. Using the driving support systems
4
Driving
Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears
When a vehicle is detected running ahead of you, the system automatically decelerates
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). The system will respond to changes in
the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by
the driver. Approach warning warns you when th e system cannot decelerate sufficiently to
prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehi cle will also stop (vehicle is stopped by sys-
tem control). After the vehicle ahead starts off, pressing the “+RES” switch or depressing
the accelerator pedal (start-off operation) will resume follow-up cruising. If the start-off
operation is not performed, system contro l continues to keep your vehicle stopped.
When the turn signal lever is operated and yo ur vehicle moves to an overtaking lane while
driving at 50 mph (80 km/h) or more, the vehicle will accelerate to help to overtake a
passing vehicle.
The system’s identification of what is an over taking lane may be determined solely based on
the location of the steering wheel in the vehicl e (left side driver position versus right side
driver position.) If the vehicle is driven to a re gion where the overtaking lane is on a different
side from where the vehicle is normally driven, the vehicle may accelerate when the turn
signal lever is operated in the opposite direction to the overtaking lane (e.g., if the driver
normally operates the vehicle in a region where the overtaking lane is to the right but then
drives to a region where the overtaking lane is to the left, the vehicle may accelerate when
the right turn signal is activated).
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 re ached. The system then returns to constant
speed cruising.
1 Press the cruise control main switch
to activate the cruise control.
Dynamic radar cruise control indicator will
come on and a message will be displayed
on the multi-information display. Press the
switch again to deactivate the cruise con-
trol.
If the cruise control ma in switch is pressed
and held for 1.5 seconds or more, the sys-
tem turns on in constant speed control mode. (
P.261)
2 Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
B
C
Setting the vehicle speed (vehi-
cle-to-vehicle distance control
mode)
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2754-5. Using the driving support systems
4
Driving
■If a battery terminal has been discon-
nected and reconnected
The system needs to be initialized. To initial-
ize the system, drive the vehicle straight
ahead for 5 seconds or more at a speed of
approximately 22 mph (35 km/h) or more.
Additionally, for vehicles with the Parking
Support Brake function, turn the steering
wheel fully to the left and right with the vehi-
cle stopped.
■Sensor detectio n information
●The following situations may occur
during use.
• The sensors may be able to only detect
objects near the front and rear bumpers.
• Depending on the shape of the object and other factors, the detection distance
may shorten, or detection may be impos-
sible.
• There will be a short delay between
object detection and display. Even at low
speeds, there is a possibility that the
object will come within the sensor’s
detection areas before the display is
shown and the warning beep sounds.
• It might be difficult to hear the buzzer due
to the volume of the audio system or air
flow noise of the air conditioning system.
• It may be difficult to hear the buzzer if
buzzers for other systems are sounding.
■Conditions under which the function
may not function correctly
Certain vehicle conditions and the sur-
rounding environment may affect the ability
of a sensor to correctly detect objects. Par-
ticular instances where this may occur are
listed below.
●There is dirt, snow, water drops or ice on
a sensor. (Cleaning the sensors will
resolve this problem.)
●A sensor is frozen. (Thawing the area will
resolve this problem.)
In especially cold weather, if a sensor is
frozen the sensor display may be dis-
played abnormally, or objects, such as a
wall, may not be detected.
●A sensor is covered in any way.
●When a sensor or the area around a sen-
sor is extremely hot or cold.
●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 sensors in the vicinity.
●A sensor is coated with a sheet of spray
or heavy rain.
●If a sensor is hit by a large amount of
water, such as when driving on a flooded
road.
●If the vehicle is significantly tilted.
●The vehicle is approaching a tall or
curved curb.
●If objects draw too close to the sensor.
■Objects which may not be properly
detected
The shape of the object may prevent the
sensor from detectin g it. Pay particular
attention to the following objects:
●Wires, fences, ropes, etc.
●Cotton, snow and other materials that
absorb sound waves
●Sharply-angled objects
●Low objects
●Tall objects with upper sections project-
ing outwards in the direction of your vehi-
cle
People may not be de tected if they are
wearing certain types of clothing.
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2844-5. Using the driving support systems
*:If equipped
■Parking Support Brake function
(static objects)
Ultrasonic sensors are used to detect
static objects, such as a wall, in the
detection area when driving at a low
speed or backing up. ( P.288)
■Parking Support Brake function
(rear-crossing vehicles)
Rear radar sensors are used to detect
approaching vehicles in the detection
area behind the vehicle when backing
up. ( P.293)
■Parking Support Brake function
(rear pedestrians) (if equipped)
A rear camera sensor is used to detect
pedestrians in the detection area
behind the vehicle when backing up.
( P.296)PKSB (Parking Support
Brake)*
The Parking Support Brake system
consists of the following functions
that operate when driving at a low
speed or backing up, such as when
parking. When the system deter-
mines that a collision with a
detected object or pedestrian is
high, a warning operates to urge
the driver to take evasive action. If
the system determines that the pos-
sibility of a collision with a detected
object or pedestrian is extremely
high, the brakes are automatically
applied to help avoid the collision or
help reduce the impact of the colli-
sion.
PKSB (Parking Support Brake)
system
WARNING
■Limitations of the Parking Support
Brake system
Do not overly rely on the system, as
doing so may lead to an accident. Always
drive while checking th e safety of the sur-
roundings of the vehicle.
Depending on the vehicle and road con-
ditions, weather, etc., the system may not
operate.
The detection capab ilities of sensors,
radars and camera are limited. Always
drive while checking th e safety of the sur-
roundings of the vehicle.
●Do not attempt to test the operation of
this system by driving the vehicle
toward another vehicle, a person or
detected object, as it may not operate
properly, possibly leading to an acci-
dent.
●The driver is solely responsible for safe
driving. Always drive carefully, taking
care to observe your surroundings.
The Parking Support Brake system is
designed to provide support to lessen
the severity of collisions. However, it
may not operate in some situations.
●The Parking Support Brake system is
not designed to stop the vehicle com-
pletely. Additionally, even if the system
has stopped the vehicl e, it is necessary
to depress the brake pedal immedi-
ately as brake control will be canceled
after approximately 2 seconds.
Page 286 of 520

2864-5. Using the driving support systems
The system determined that emergency
braking is necessary.
Center Display (Panoramic view monitor):
“BRAKE!”
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illuminated
Buzzer: Short beep
Vehicle stopped by system opera-
tion
The vehicle has been stopped by brake
control operation.
Center Display (Panoramic view monitor):
“Press Brake Pedal”
Multi-information display: “Switch to
Brake” (If the accelerator pedal is not
depressed, “Press Brake Pedal” will be dis-
played.)
PKSB OFF indicator: Illuminated
Buzzer: Short beep
If the Parking Support Brake deter-
mines that a collision with a detected
object or pedestrian is possible, the
engine output will be restricted to
restrain any increase in the vehicle
speed. (Engine output restriction con-
trol: See figure 2.)
Additionally, if the accelerator pedal
continues to be depressed, the brakes
will be applied automatically to reduce
the vehicle speed. (Brake control: See
figure 3.)
Figure 1 When the PKSB (Parking
Support Brake) is disabled Engine output
Braking force
Time
Figure 2 When engine output
restriction control operates
Engine output
Braking force
Time
Engine output re striction control
begins operating
System determines that possibility
of collision with detected object is
high
Engine output reduced
Example: Multi-information display:
“BRAKE!”
Figure 3 When brake control oper-
ates
System overview
A
B
C
A
B
C
D
E
F
G
Page 292 of 520

2924-5. Using the driving support systems
to normal)
• If heavy rain or water strikes a sensor
• When driving in incl ement weather such
as fog, snow or a sandstorm
• When strong winds are blowing
●Other ultrasonic wave sources
• When vehicle horns, vehicle detectors, motorcycle engines, air brakes of large
vehicles, the clearance sonar of other
vehicles or other devices which produce
ultrasonic waves are near the vehicle
• If a sticker or an el ectronic component,
such as a backlit license plate (especially
fluorescent type), fog lights, fender pole
or wireless antenna is installed near a
sensor
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or low- ered due to the carried load
• If the orientation of a sensor has been changed due to a collision or other
impact
■Situations in which the Parking Support
Brake function (stati c objects) may not
operate properly
In some situations, such as the following, this
function may not operate properly.
●Weather
• When a sensor or the area around a sen-
sor is extremely hot or cold
• When strong winds are blowing
• If a sensor is covered with water drops, ice, snow, dirt, etc. (when cleared, the sys-
tem will return to normal)
• If heavy rain or water strikes a sensor
• When driving in incl ement weather such
as fog, snow or a sandstorm
• When the sensor is frozen (Once the
sensor thaws, the system will return to
normal)
●Vehicle surroundings
• When an object that cannot be detected is between the vehicle and a detected
object
• If an object such as a vehicle, motorcycle, bicycle or pedestrian cuts in front of the
vehicle or runs out from the side of the
vehicle
• The vehicle is approaching a tall or
curved curb.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• If objects draw too close to the sensor.
●Other ultrasonic waves sources
• When vehicle horns, vehicle detectors, motorcycle engines, air brakes of large
vehicles, the clearance sonar of other
vehicles or other de vices which produce
ultrasonic waves are near the vehicle
• If a sticker or an electronic component,
such as a backlit license plate (especially
fluorescent type), fog lights, fender pole
or wireless antenna is installed near a
sensor
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or low- ered due to the carried load
• If the orientation of a sensor has been
changed due to a collision or other
impact
• When equipment that may obstruct a sensor is installed, such as a towing eye-
let, bumper protector (an additional trim
strip, etc.), bicycle carrier, or snow plow
• If the suspension has been modified or tires of a size othe r than specified are
installed
• If a sensor has been painted or covered with a sticker, etc.
Page 296 of 520

2964-5. Using the driving support systems
• When backing out of a shallow angle parking spot
• When backing up on a slope with a sharp change in grade
• When a vehicle turns into the detection area
*: If equipped
When a pedestrian is detected behind
the vehicle while backing up, the brake
pedal is not depressed or is depressed
late.
Displays a message to urge the driver
to take evasive action when a pedes-
trian is detected in the detection area
behind the vehicle. (A message will
also be displayed on the multi-informa-
Parking Support Brake func-
tion (rear pedestrians)*
If the rear camera sensor detects a
pedestrian behind the vehicle while
backing up and the system deter-
mines that the possibility of collid-
ing with the detected pedestrian is
high, a buzzer will sound. If the sys-
tem determines that the possibility
of colliding with the detected
pedestrian is extremely high, the
brakes will be applied automatically
to help reduce the impact of the
collision.
Examples of system operation
Center Display
Page 304 of 520

3044-5. Using the driving support systems
■ECB (Electronically Controlled
Brake System) (vehicles with Lexus
Safety System + A)
The electronically controlled system
generates braking force correspond-
ing to the brake operation
■ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the
brakes are applied suddenly, or if the
brakes are applied while driving on a
slippery road surface
■Brake assist
Generates an increased level of brak-
ing 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 sudden ly or turning on
slippery road surfaces.
■TRAC (Traction Control)
Helps to maintain drive power and pre-
vent the drive wheels from spinning when starting the vehicle or accelerat-
ing on slippery roads
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■VGRS (Variable Gear Ratio Steer-
ing) (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 characteris-
tics and responsiveness of the vehicle
by adjusting the rear wheel angle of the
vehicle in accordance with steering
wheel movement.
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel.
■Active stabilizer suspension sys-
tem (if equipped)
Reduces sway when cornering accord-
ing to steering wheel movement in
order to maintain a stable vehicle pos-
ture.
■Adaptive Variable Suspension Sys-
tem (if equipped)
By independently controlling the
damping force of th e shock absorbers
for each of the 4 wheels according to
the road and driving conditions, this
system helps riding comfort with supe-
rior vehicle stability, and helps good
Driving assist systems
To keep driving safety and perfor-
mance, 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 oper-
ating the vehicle.
Summary of the driving assist
systems
Page 305 of 520

3054-5. Using the driving support systems
4
Driving
vehicle posture.
Also, the damping force changes
depending on the selected driving
mode. (P.299)
■LDH (Lexus Dynamic Handling
system) (if equipped)
Provides integrated control of the
VGRS, DRS and EPS. Contributes to
turning characteristics at low speeds,
responsiveness at medium speeds and
safety at high speeds by controlling the
steering angle of the front and rear
wheels in accordance with the steering
wheel operation and vehicle speed.
■VDIM (Vehicle Dynamics Inte-
grated Management)
Provides integrated control of the
ABS, brake assist, TRAC, VSC,
hill-start assist control, EPS, VGRS (if
equipped), DRS (if equipped), active
stabilizer suspension system (if
equipped) and Adaptive Variable Sus-
pension System (if equipped)
Helps to maintain vehicle stability when
swerving on slippery road surfaces by
controlling the brakes, engine output,
steering assist, and steering ratio
■The Secondary Collision Brake
When the SRS airbag sensor detects a
collision and the system operates, the
brakes and stop lights are automati-
cally controlled to reduce the vehicle
speed and help redu ce the possibility
of further damage due to a secondary
collision.
■When the TRAC/VSC systems are
operating (vehicles without Lexus
Safety System + A)
The slip indicator light will flash while the
TRAC/VSC systems are operating.
■When the TRAC/VSC/ABS systems are
operating (vehicles with Lexus Safety
System + A)
The slip indicator light will flash while the
TRAC/VSC/ABS systems are operating.
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow,
the TRAC system may reduce power from
the engine to the wheels. Pressing the
switch to turn the system off may make it
easier for you to rock the vehicle in order to
free it.
To turn the TRAC system off, quickly press
and release the switch.
The “Traction Co ntrol Turned Off” will be
shown on the multi-information display.
Press the switch ag ain to turn the sys-
tem back on.