1804-5. Using the driving support systems
WARNING
■Limitations of the pre-collision sys-
tem
●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.182
• Conditions under which the system may not operate properly: P.184
●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 stopped by the opera-
tion of the pre-collision braking func-
tion, the pre-collision braking function
operation will be canceled after
approximately 2 seconds.
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 can-
celed if the accelerator 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
●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
1824-5. Using the driving support systems
system determines that the possibility of a
frontal collision with a vehicle or pedestrian
is high.
Each function is operational at the following
speeds:
●Pre-collision warning:
• Vehicle speed is be tween 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 be tween 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 be tween 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.
The system may not operate in the following
situations:
●If a battery terminal has been discon-
nected and reconnected and then the
vehicle has not been driven for a certain
amount of time
●If the shift position is in R
●If VSC is disabled (only the pre-collision
warning function will be operational)
■Pedestrian detection function
The pre-collision system detects pedestri-
ans based on the size, profile, and motion of
a detected object. However, a pedestrian
may not be detected depending on the sur-
rounding brightness and the motion, pos-
ture, and angle of the detected object,
preventing the system from operating properly. (
P.184)
■Cancelation of the pre-collision braking
If either of the follo wing occur while the
pre-collision braking fu nction 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 there is no possibility of a
collision
●In some situations su ch as the following,
the system may determine that there is a
possibility of a frontal collision and oper-
ate.
• When passing a vehicle or pedestrian
• When changing lanes while overtaking a
preceding vehicle
• When overtaking a preceding vehicle
that is changing lanes
• 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
1854-5. Using the driving support systems
4
Driving
• 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, guard-
rails, 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.220), the pre-
collision brake assist and pre-collision
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.
1964-5. Using the driving support systems
This mode employs a radar sensor to detect the presence of vehicles up to approx-
imately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle following
distance, and operates to maintain 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 distance
can also be set by operating the ve hicle-to-vehicle distance switch.
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 will resume follow-up cruising.
WARNING
●During emergency towing
●When an approach warning buzzer is
heard often
Driving in vehicle-to-vehicle distance control mode
A
B
1994-5. Using the driving support systems
4
Driving
After the vehicle ahead of you starts
off, press the “+RES” switch.
Your vehicle will also resume follow-
up cruising if the accelerator pedal is
depressed after the vehicle ahead of
you starts off.1
Pressing the cancel switch 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.)
2Pressing the “+RES” switch
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
25 mph (40 km/h) 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 appropri-
ate vehicle-to-vehicle distance.
MediumApproximately 130 ft. (40 m)
ShortApproximately 100 ft. (30 m)
Resuming follow-up cruising
when the vehicle has been
stopped by system control (vehi-
cle-to-vehicle distance control
mode)
Distance optionsVehicle-to-vehicle distanceCanceling and resuming the
speed control
Approach warning (vehicle-to-
vehicle distance control mode)
2014-5. Using the driving support systems
4
Driving
mately 30 mph (50 km/h).
However, when a preceding vehicle is
detected, the dynamic radar cruise con-
trol with full-speed range can be set even
if the vehicle speed is below approxi-
mately 30 mph (50 km/h).
■Accelerating after setting the vehicle
speed
The vehicle can accelerate by operating the
accelerator pedal. After accelerating, the
set speed resumes. However, during vehi-
cle-to-vehicle distance control mode, the
vehicle speed may decrease below the set
speed in order to maintain the distance to
the preceding vehicle.
■When the vehicle stops while follow-up
cruising
●Pressing the “+RES” switch while the
vehicle ahead stops will resume follow-
up cruising if the vehicle ahead starts off
within approximately 3 seconds after the
switch is pressed.
●If the vehicle ahead starts off within 3 sec-
onds after your vehicle stops, follow-up
cruising will be resumed.
■Automatic cancelation of vehicle-to-
vehicle distance control mode
Vehicle-to-vehicle dist ance control mode is
automatically canceled in the following situ-
ations:
●Actual vehicle speed falls at or below
approximately 25 mph (40 km/h) when
there are no vehicles ahead.
●The preceding vehicle leaves the lane
when your vehicle is following at a vehicle
speed at or below approximately 25 mph
(40 km/h). Otherwise, the sensor can
not properly detect the vehicle.
(“CRUISE NOT AVAILABLE No Pre-
ceding Vehicles” is displayed on the
multi-information display)
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is
turned off.
●When snow mode is set.
●The sensor cannot detect correctly
because it is covered in some way.
●Pre-collision braking is activated.
●The parking brake is operated.
●The vehicle is stopped by system control
on a steep incline.
●The following are detected when the
vehicle has been stopped by system con-
trol:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes
If vehicle-to-vehicle distance control mode
is automatically canceled for any other rea-
son, there may be a malfunction in the sys-
tem. Contact your Lexus dealer.
■Automatic cancelation of constant
speed control mode
Constant speed control mode is automati-
cally canceled in the following situations:
●Actual vehicle speed is more than
approximately 10 mph (16 km/h) below
the set vehicle speed.
●Actual vehicle speed falls below approxi-
mately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is
turned off.
●Pre-collision braking is activated.
If constant speed control mode is automati-
cally canceled for any other reason, there
may be a malfunction in the system. Con-
tact your Lexus dealer.
■Brake system operation sound
If the brakes are app lied automatically while
the vehicle is in vehicle-to-vehicle distance
control mode, a brake system operation
sound may be heard. This does not indicate
a malfunction.
■If “Radar Cruise Control Unavailable” is
shown on the multi-information display
The radar cruise control system cannot be
used temporarily. Use the system when it
becomes available again.
2024-5. Using the driving support systems
■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.
■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 insuffi-
cient 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.199) 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 detect-
ing of the sensor
●When your vehicle is pointing upwards
(caused by a heavy load in the luggage
compartment, etc.)
●Preceding vehicle has an extremely high
ground clearance
■Conditions under which the vehicle-to-
vehicle distance control mode may not
function correctly
In the case of the following conditions,
operate the brake pedal (or accelerator
pedal, depending on the situation) as nec-
essary.
As the sensor may not be able to correctly
detect vehicles ahead, the system may not
operate properly.
●When the road curves or when the lanes
are narrow
●When steering wheel operation or your
position in the lane is unstable
●When the vehicle ahead of you deceler-
ates suddenly
●When driving on a road surrounded by a
structure, such as in a tunnel or on a
bridge
●While the vehicle speed is decreasing to
the set speed after the vehicle acceler-
ates by depressing the accelerator pedal
2064-5. Using the driving support systems
■If “Clean Parking Assist Sensor” is dis-
played on the multi-information display
A sensor may be dirty or covered with snow
or ice. In such cases, if it is removed from
the sensor, the system should return to nor-
mal.
Also, due to the sensor being frozen at low
temperatures, a malfunction display may
appear or an obstacle may not be detected.
If the sensor thaws out, the system should
return to normal.
■If “Parking Assist Malfunction” or
“Parking Assist Malfunction Visit Your
Dealer” is displayed on the multi-infor-
mation display
There is a malfunction and the device may
not be working properly.
Have the vehicle inspected by your Lexus
dealer.
■Sensor detectio n information
●The sensor’s detection areas are limited
to the areas around the vehicle’s front
and rear bumpers.
●Certain vehicle conditions and the sur-
rounding 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
problem.)
• The sensor is frozen. (Thawing the 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 considerably 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, be cause 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 particu-
lar 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 pro- jecting outwards in the direction of your
vehicle
●The following situations may occur
during use.
• Depending on the shape of the obstacle and other factors, the detection distance
may shorten, or detection may be impos-
sible.
• Obstacles may not be detected if they are too close to the sensor.
• There will be a short delay between obstacle detection and display. Even at
slow speeds, there is a possibility that the
obstacle will come within the sensor’s
detection areas befo re the display is
shown and the warning beep sounds.
• Thin posts or object s lower than the sen-
sor 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.
• It might be difficult to hear beeps due to the sounds of other systems.