2474-5. Using the driving support systems
4
Driving
■ECB (Electronically Controlled
Brake System)
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
■Enhanced VSC (Enhanced Vehi-
cle 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 perfor-
mance.
■Secondary Collision Brake
When the SRS airbag sensor detects a
collision and the system operates, the
brakes and brake lights are automati-
cally controlled to reduce the vehicle
speed and that help reduce the possi-
bility of further damage due to a sec-
ondary collision
■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
■Active Cornering Assist (ACA)
Helps to prevent the vehicle from drift-
ing to the outer side by performing
inner wheel brake control when
attempting to accele rate while turning
■Hill-start assist control
Helps to reduce the backward move-
ment of the vehicle when starting on an
uphill
■EPS (Electric Power Steering)
Employs an electric motor to reduce
the amount of effort needed to turn the
steering wheel
■When the TRAC/VSC/ABS systems are
operating
The slip indicator light will flash while the
TRAC/VSC/ABS systems are operating.
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
2484-5. Using the driving support systems
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt or snow,
the TRAC system may reduce power from
the hybrid system 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.
“Traction Control Turned Off” will be shown
on the multi-information display.
Press the switch again to turn the sys-
tem back on.
■Turning off both TRAC and VSC sys-
tems
To turn the TRAC and VSC systems off,
press and hold the switch for more
than 3 seconds while the vehicle is stopped.
The VSC OFF indicator light will come on
and the “Traction Cont rol Turned Off” will
be shown on the multi-information display.
*
Press the switch again to turn the sys-
tem back on.
*: PCS (Pre-Collision System) will also be disabled (only Pre-Collision warning is
available). The PCS warning light will come on and a message
will be displayed
on the multi-information display.
( P.184)
■When the message is displayed on the
multi-information display showing that
TRAC has been disabled even if the
switch has not been pressed
TRAC is temporary deactivated. If the infor-
mation continues to show, contact your
Lexus dealer.
■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/back-
ward on an up ward 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 shifted to P or N.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●2 seconds at maximum elapsed after the
brake pedal is released.
■Sounds and vibrations caused by the
ABS, brake assist, VSC, TRAC and hill-
start assist control systems
●A sound may be heard from the engine
compartment when the brake pedal is
depressed repeatedly, when the hybrid
system is started or just after the vehicle
begins to move. This sound does not indi-
cate 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.
2494-5. Using the driving support systems
4
Driving
• A motor sound may be heard also after the vehicle comes to a stop.
■ECB operating sound
ECB operating sound may be heard in the
following cases, but it does not indicate that
a malfunction has occurred.
●Operating sound heard from the engine
compartment when the brake pedal is
operated.
●Motor sound of the brake system heard
from the front part of the vehicle when
the driver’s door is opened.
●Operating sound heard from the engine
compartment when one or two minutes
passed after the stop of the hybrid sys-
tem.
■Active Cornering Assist operation
sounds and vibrations
When the Active Cornering Assist is oper-
ated, operation sounds and vibrations may
be generated from the brake system, but
this is not a malfunction.
■EPS 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 and
VSC systems
After turning the TRAC and VSC systems
off, the systems will be automatically re-
enabled in the following situations:
●When the power 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.
■Secondary Collision Brake operating
conditions
The system operates when the SRS airbag
sensor detects a collision while the vehicle
is in motion.
However, the system does not operate in
any of the following situations.
●The vehicle speed is below 6 mph (10
km/h)
●Components are damaged
■Secondary Collision Brake automatic
cancellation
The system is automatically canceled in any
of the following situations.
●The vehicle speed drops below approxi-
mately 6 mph (10 km/h)
●A certain amount of time elapses during
operation
●The accelerator pedal is depressed a
large amount
■Operating conditions of Active Corner-
ing Assist
The system operates when the following
occurs.
●TRAC/VSC can operate
●The driver is attempting to accelerate
while turning
●The system detects that the vehicle is
drifting to the outer side
●The brake pedal is released
■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, refrain from excessive
steering input or stop the vehicle and turn
the hybrid system 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.
2504-5. Using the driving support systems
WARNING
■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.
■Active Cornering Assist does not
operate effectively when
●Do not overly rely on Active Corner-
ing Assist. Active Cornering Assist
may not operate effectively when
accelerating down slopes or driving on
slippery road surfaces.
●When Active Cornering Assist fre-
quently operates, Active Cornering
Assist may temporarily stop operating
to ensure proper operation of the
brakes, TRAC and VSC.
■Hill- start assist control does not
operate 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/ABS/VSC is acti-
vated
The slip indicator light flashes. Always
drive carefully. Reckless 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.
■Secondary Collision Brake
Do not rely solely upon the Secondary
Collision Brake. This system is designed
to help reduce the possibility of further
damage due to a secondary collision,
however, that effect changes according
to various conditions. Overly relying on
the system may result in death or serious
injury.
■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 suspensi on will affect the
driving assist systems, and may cause a
system to malfunction.
3256-3. Do-it-yourself maintenance
6
Maintenance and care
■Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN” lines
on the tank.
■Adding fluid
Make sure to check the fluid type and
prepare the necessary items.
Fluid type
FMVSS No.116 DOT 3 or SAE J1703
brake fluid
FMVSS No.116 DOT 4 or SAE J1704
brake fluid
Item
Clean funnel
■Brake fluid can absorb moisture from
the air
Excess moisture in the brake fluid can cause
a dangerous loss of braking efficiency. Use
only newly opened brake fluid.
If any washer does not work or “Wind-
shield Washer Fluid Low” is shown on
the multi-information display, the
washer tank may be empty. Add
washer fluid.
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser
as they may be hot and cause serious
injuries, such as burns.
Checking and adding the brake
fluid
WARNING
■When filling the reservoir
Take care as brake fluid can harm your
hands and eyes and damage painted sur-
faces.
If fluid gets on your hands or in your eyes,
flush the affected area with clean water
immediately.
If you still experience discomfort, see a
doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go
down slightly as the brake pads wear out
or when the fluid leve l in the accumulator
is high.
If the reservoir need s frequent refilling,
there may be a serious problem.
Adding the washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid
system is hot or operating as washer fluid
contains alcohol and may catch fire if
spilled on the engine etc.
3667-2. Steps to take in an emergency
■ABS warning light (warning buzzer)
■Brake Override System warning light/Drive-Start Control warning light*
(warning buzzer)
*: This light illuminates on the multi-information display.
■Electric power steering system warning light (warning buzzer)
Warning lightDetails/Actions
(U.S.A.)
or
(Canada)
Indicates a malfunction in:
The ABS; or
The brake assist system
Have the vehicle inspected by your Lexus dealer immediately.
Warning lightDetails/Actions
When a buzzer sounds:
Brake Override System is malfunctioning;
Drive-Start Control is operating; or
Drive-Start Control is malfunctioning
Follow the instructions displayed on the multi-information display.
When a buzzer does not sound:
Brake Override System is operating
Release the accelerator pedal and depress the brake pedal.
Warning lightDetails/Actions
(red)
or
(yellow)
Indicates a malfunction in the EPS (Electric Power Steering) system
Have the vehicle inspected by your Lexus dealer immediately.
3727-2. Steps to take in an emergency
If the tire pressure warning light blinks for
approximately 1 minute then stays on
There may be a malfunction in the tire pres-
sure warning system. Have the vehicle
inspected by your Lexus dealer immedi-
ately.
If the tire pressure warning light comes
on
1
After the temperature of the tires has
lowered sufficiently, check the inflation
pressure of each tire and adjust them to
the specified level.
2
If the warning light does not turn off
even after several minutes have
elapsed, check that the inflation pres-
sure of each tire is at the specified level
and perform initialization. ( P.334)
■The tire pressure warning light may
come on due to natural causes
The tire pressure warning light may come
on due to natural causes such as natural air
leaks and tire inflation pressure changes
caused by temperature. In this case, adjust-
ing the tire inflation pressure will turn off the
warning light (after a few minutes).
■When a tire is replaced with a spare tire
The compact spare tire is not equipped with
a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warn-
ing light will not turn off even though the flat
tire has been replaced with the spare tire.
Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The
tire pressure warning lig ht will go off after a
few minutes.
■Conditions that the tire pressure warn-
ing system may not function properly
P.332
WARNING
■If both the ABS and the brake system
warning lights remain on
Stop your vehicle in a safe place immedi-
ately and contact your Lexus dealer.
The vehicle will become extremely
unstable during braking, and the ABS
system may fail, which could cause an
accident resulting in death or serious
injury.
■When the electric power steering
system warning light comes on
When the light comes on yellow, the
assist to the power st eering is restricted.
When the light comes on red, the assist
to the power steering is lost and handling
operations of the steering wheel become
extremely heavy.
When steering wheel operations are
heavier than usual, grip the steering
wheel firmly and operate it using more
force than usual.
■If the tire pressure warning light
comes on
Be sure to observe the following precau-
tions.
Failure to do so could cause a loss of
vehicle control and result in death or
serious injury.
●Stop your vehicle in a safe place as
soon as possible. Check and adjust the
tire inflation pre ssure immediately.
●If the tire pressure warning light comes
on even after tire inflation pressure
adjustment, it is prob able that you have
a flat tire. Check the tire s. If a tire is flat,
change it with the spare tire and have
the flat tire repaired by the nearest
Lexus dealer.
●Avoid abrupt maneuvering and brak-
ing.
If the vehicle tires deteriorate, you
could lose control of the steering
wheel or the brakes.
3847-2. Steps to take in an emergency
76 ft•lbf (103 N•m, 10.5 kgf•m)
5Stow the flat tire, tire jack and all
tools.
■The compact spare tire
●The compact spare tire is identified by the
label “TEMPORARY USE ONLY” on
the tire sidewall.
Use the compact spare tire temporarily,
and only in an emergency.
●Make sure to check the tire inflation pres-
sure of the compact spare tire. (P.405)
■After completing the tire change
The tire pressure warning system must be
reset. ( P.333)
■When using the compact spare tire
As the compact spare tire is not equipped
with a tire pressure warning valve and trans-
mitter, low inflation pressure of the spare
tire will not be indicated by the tire pressure
warning system. Also, if you replace the
compact spare tire after the tire pressure
warning light comes on, the light remains
on.
■When the compact spare tire is
attached
The vehicle becomes lower when driving
with the compact spar e tire compared to
when driving with standard tires.
■If you have a flat front tire on a road cov-
ered with snow or ice
Install the compact spare tire on one of the
rear wheels of the vehicle. Perform the fol-
lowing steps and fit tire chains to the front
tires: 1
Replace a rear tire with the compact
spare tire.
2
Replace the flat front tire with the tire
removed from the rear of the vehicle.
3
Fit tire chains to the front tires.
WARNING
■When using the compact spare tire
●Remember that the compact spare tire
provided is specific ally designed for
use with your vehicle. Do not use your
compact spare tire on another vehicle.
●Do not use more than one compact
spare tire simultaneously.
●Replace the compact spare tire with a
standard tire as soon as possible.
●Avoid sudden acceleration, abrupt
steering, sudden braking and shifting
operations that cause sudden engine
braking.
■When the compact spare tire is
attached
The vehicle speed may not be correctly
detected, and the following systems may
not operate correctly:
• ABS & Brake assist
• VSC
• TRAC
• Dynamic radar cruise control with full- speed range
• PCS (Pre-Collision System)
• EPS
• LTA (Lane Tracing Assist)
• Panoramic view monitor (if equipped)
• Lexus parking assist monitor (if equipped)
• Intuitive parking assist (if equipped)
• Navigation system (if equipped)
• BSM (Blind spot monitor) (if equipped)
• Automatic high Beam