2394-5. Using the driving support systems
4
Driving
WARNING
●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 rely solely upon Active Cor-
nering 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, 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 overly rely on the Secondary Col-
lision 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.
2424-6. Driving tips
Use fluids that are appropriate to
the prevailing outside temperatures.
• Engine oil
• Engine coolant/power control unit cool-
ant
• Washer fluid
Have a service technician inspect
the condition of the 12-volt battery.
Have the vehicle fitted with four
snow tires or purchase a set of tire
chains for the front tires.
*
Ensure that all tires are the specified size
and brand, and that chains match the size
of the tires.
*: Tire chains cannot be mounted on vehi-
cles with 18-inch tires.
Perform the following according to the
driving conditions:
Do not try to forcibly open a window
Winter driving tips
Carry out the necessary prepara-
tions and inspections before driving
the vehicle in winter. Always drive
the vehicle in a manner appropriate
to the prevailing weather condi-
tions.
Preparation for winter
WARNING
■Driving with snow tires
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in a loss of
vehicle control and cause death or seri-
ous injury.
●Use tires of the specified size.
●Maintain the recommended level of air
pressure.
●Do not drive in excess of 75 mph (120
km/h), regardless of the type of snow
tires being used.
●Use snow tires on all, not just some
wheels.
■Driving with tire chains (vehicles with
17-inch tires)
Observe the following precautions to
reduce the risk of accidents.
Failure to do so may result in the vehicle
being unable to be driven safely, and may
cause death or serious injury.
●Do not drive in excess of the speed
limit specified for the tire chains being
used, or 30 mph (50 km/h), which-
ever is lower.
●Avoid driving on bumpy road surfaces
or over potholes.
●Avoid sudden acceleration, abrupt
steering, sudden br aking and shifting
operations that cause sudden engine
braking.
●Slow down sufficiently before entering
a curve to ensure that vehicle control is
maintained.
●Do not use LTA (Lane Tracing Assist)
system.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow
tires from Lexus dealers or legitimate tire
retailers.
This is because the removal and attach-
ment of snow tires affects the operation
of the tire pressure warning valves and
transmitters.
Before driving the vehicle
2434-6. Driving tips
4
Driving
or move a wiper that is frozen. Pour
warm water over the frozen area to
melt the ice. Wipe away the water
immediately to prevent it from
freezing.
To ensure proper operation of the
climate control system fan, remove
any snow that has accumulated on
the air inlet vents in front of the
windshield.
Check for and remove any excess
ice or snow that may have accumu-
lated on the exterior lights, vehicle’s
roof, chassis, around the tires or on
the brakes.
Remove any snow or mud from the
bottom of your shoes before getting
in the vehicle.
■To protect the windshield wipers
P.158
Accelerate the vehicle slowly, keep a
safe distance between you and the
vehicle ahead, and drive at a reduced
speed suitable to road conditions.
Park the vehicle and move the shift
lever to P without setting the park-
ing brake. The parking brake may
freeze up, preventing it from being
released. If the vehicle is parked
without setting the parking brake,
make sure to block the wheels.
Failure to do so may be dangerous
because it may cause the vehicle to move unexpectedly, possibly lead-
ing to an accident.
If the vehicle is parked without set-
ting the parking brake, confirm that
the shift lever cannot be moved out
of P
*.
*: The shift lever will be locked if it is
attempted to be shifted from P to any
other position with out depressing the
brake pedal. If the shift lever can be
shifted from P, there may be a problem
with the shift lock system. Have the vehi-
cle inspected by your Lexus dealer
immediately.
Vehicles with 17-inch tires
Use the correct tire chain size when
mounting the tire chains.
Chain size is regulated for each tire
size.
Side chain:
0.12 in. (3 mm) in diameter
0.39 in. (10 mm) in width
1.18 in. (30 mm) in length
Cross chain:
0.16 in. (4 mm) in diameter
0.55 in. (14 mm) in width
When driving the vehicle
When parking the vehicle
Selecting tire chains
A
B
C
D
E
3266-3. Do-it-yourself maintenance
Check if the treadwear indicators are
showing on the tires. Also check the
tires for uneven wear, such as excessive
wear on one side of the tread.
Check the spare tire condition and
pressure if not rotated.New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is
shown by a “TWI” or “ ” mark, etc.,
molded into the sidewall of each tire.
Replace the tires if the treadwear indica- tors are showing on a tire.
■When to replace your vehicle’s tires
●Tires should be replaced if:
• The treadwear indicators are showing on a tire.
• You have tire damage such as cuts, splits,
cracks deep enough to expose the fabric,
and bulges indicating internal damage
• A tire goes flat repeatedly or cannot be
properly repaired due to the size or loca-
tion of a cut or other damage
If you are not sure, consult your Lexus
dealer.
●Vehicles with 17-inch tires:
The wheel angle differs from vehicles
equipped with 18-inch tires. Therefore, 18-
inch tires cannot be installed, as sufficient
gaps with surrounding parts cannot be
ensured.
■Tire life
Any tire over 6 years old must be checked
by a qualified technician even if it has sel-
dom or never been used or damage is not
obvious.
■Low profile tires (18-inch tires)
Generally, low profile tires will wear more
rapidly and tire grip performance will be
reduced on snowy and/or icy roads when
compared to standard tires. Be sure to use
snow tires on snowy and/or icy roads and
drive carefully at a speed appropriate for
road and weather conditions.
■Maximum load of tire
Check that the maximum load of the
replacement tire is greater than 1/2 of the
Gross Axle Weight Ratings (GAWR) of
either the front axle or the rear axle, which-
ever is greater.
For the GAWR, see the Certification Label.
For the maximum load of the tire, see the
load limit at maximum cold tire inflation
pressure mentioned on the sidewall of the
tire. ( P.403)
Tires
Replace or rotate tires in accor-
dance with maintenance schedules
and treadwear.
Checking tires
A
B
C
3276-3. Do-it-yourself maintenance
6
Maintenance and care
■Tire types
●Summer tires
Summer tires are high-speed perfor-
mance tires best suited to highway driv-
ing under dry conditions. Since summer
tires do not have the same traction per-
formance as snow tires, summer tires are
inadequate for driving on snow-covered
or icy roads. For driving on snow-covered
roads or icy roads, the use of snow tires is
recommended. When installing snow
tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide
better traction in snow and to be ade-
quate for driving in most winter condi-
tions as well as for use year-round. All
season tires, however, do not have ade-
quate traction performance compared
with snow tires in heavy or loose snow.
Also, all season tires fall short in accelera-
tion and handling performance com-
pared with summer tires in highway
driving.
●Snow tires
For driving on snow-covered roads or icy
roads, we recommend using snow tires. If
you need snow tires, select tires of the
same size, construction and load capacity
as the originally installed tires. Since your
vehicle has radial tires as original equip-
ment, make sure your snow tires also
have radial construction. Do not install
studded tires without first checking local
regulations for possible restrictions.
Snow tires should be installed on all
wheels. ( P.242)
■If the tread on snow tires wears down
below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is
lost.
WARNING
■When inspecting or replacing tires
Observe the following precautions to
prevent accidents.
Failure to do so may cause damage to
parts of the drivetrain as well as danger-
ous handling characteristics, which may
lead to an accident resulting in death or
serious injury.
●Do not mix tires of different makes,
models or tread patterns.
Also, do not mix tires of remarkably
different treadwear.
●Do not use tire sizes other than those
recommended by Lexus.
●Do not mix differently constructed
tires (radial, bias-belted or bias-ply
tires).
●Do not tow if your vehicle has a com-
pact spare tire installed.
●Do not mix summer, all season and
snow tires.
●Do not use tires that have been used
on another vehicle.
Do not use tires if you do not know
how they were used previously.
NOTICE
■Driving on rough roads
Take particular care when driving on
roads with loose surfaces or potholes.
These conditions may cause losses in tire
inflation pressure, reducing the cushion-
ing ability of the tires. In addition, driving
on rough roads may cause damage to
the tires themselves, as well as the vehi-
cle’s wheels and body.
■Low profile tires (18-inch tires)
Low profile tires may cause greater dam-
age than usual to the tire wheel when
sustaining impact from the road surface.
Therefore, pay attention to the following:
3296-3. Do-it-yourself maintenance
6
Maintenance and care
●Tire inflation pressure changes with tem-
perature. The displayed values may also
be different from the values measured
using a tire pressure gauge.
■Situations in which the tire pressure
warning system may not operate prop-
erly
●In the following cases, the tire pressure
warning system may not operate prop-
erly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is
not an OE (Original Equipment) tire.
• A tire has been replaced with a tire that is
not of the specified size.
• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehi-
cle, particularly around the wheels or
wheel housings.
• If the tire inflation pressure is extremely
higher than the specified level.
• If wheel without tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warn- ing valves and transmitters is not regis-
tered in the tire pressure warning
computer.
●Performance may be af fected in the fol-
lowing situations.
• Near a TV tower, electric power plant,
gas station, radio stat ion, large display,
airport or other fac ility that generates
strong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless
communication device
If tire position information is not correctly
displayed due to the radio wave conditions,
the display may be corrected by driving and
changing the radio wave conditions.
●When the vehicle is parked, the time
taken for the warning to start or go off
could be extended.
●When tire inflation pr essure declines rap-
idly for example when a tire has burst, the
warning may not function.
■Warning performance of the tire pres-
sure warning system
The warning of the tire pressure warning
system will change in accordance with driv-
ing conditions. For this reason, the system
may give a warning even if the tire pressure
does not reach a low enough level, or if the
pressure is higher than the pressure that
was adjusted to when the system was initial-
ized.
■Tire pressure warning system certification
For vehicles sold in the U.S.A. , Hawaii, Guam and Puerto Rico
3316-3. Do-it-yourself maintenance
6
Maintenance and care
■The tire pressure warning system
must be initialized in the following
circumstances:
When rotating the tires.
When the tire inflation pressure is
changed when changing traveling
speed.
When the tire inflation pressure is
changed such as when changing tire
size. (When there are multiple spec-
ified pressures)
After registering the ID codes.
( P.332)
When the tire pressure warning system
is initialized, the cu rrent tire inflation
pressure is set as the benchmark pres-
sure.
■How to initialize the tire pressure
warning system
1 Park the vehicle in a safe place and
stop the hybrid system for 20 min-
utes or more.
Initialization cannot be performed while
the vehicle is moving.
2 Adjust the tire inflation pressure to
the specified cold tire inflation pres-
sure level.
Make sure to adjust th e tire pressure to the
specified cold tire infl ation pressure level.
The tire pressure warning system will oper-
ate based on this pressure level.
3 Start the hybrid system ( P.135)
4 Press or of the meter con-
trol switches and select . 5
Press or of the meter con-
trol switches and select “Vehicle
Settings”, then press “OK”.
6 Press or of the meter con-
trol switches and select “TPWS”,
then press “OK”.
7 Press or of the meter con-
trol switches and select “Set Pres-
sure”. Then press and hold “OK”
until the tire pressure warning light
starts blinking.
A message is displayed on the multi-infor-
mation display. Also, “--” is displayed for
inflation pressure of each tire on the multi-
information display while the tire pressure
warning system determines the position.
8Drive at approximately 25 mph
(40 km/h) or more for approxi-
mately 10 to 30 minutes.
When initialization is complete, the infla-
tion pressure of each tire will be displayed
on the multi-information display.
Even if the vehicle is not driven at approxi-
mately 25 mph (40 km/h) or more, initial-
ization can be completed by driving for a
long time. However, if initialization does not
complete after driving for 1 hour or more,
park the vehicle in a safe place for approxi-
mately 20 minutes and then drive the vehi-
cle again.
■When initializing
●Initialization is performed while driving at
Initializing the tire pressure
warning system
3346-3. Do-it-yourself maintenance
tration may take longer than usual to be
completed or may not be possible. Nor-
mally, registration completes within
approximately 30 minutes.
• Vehicle is not parked for approximately 20 minutes or more before driving
• Vehicle is not driven at approximately 25 mph (40 km/h) or more
• Vehicle is driven on unpaved roads
• Vehicle is driven near other vehicles and system cannot recognize tire pressure
warning valve and tran smitters of your
vehicle over those of other vehicles
• Wheel with tire pressure warning valve and transmitter installed is inside or near
the vehicle
If registration does not complete after driv-
ing for 1 hour or more, perform the ID code
registration procedure again from the
beginning.
●If the vehicle is reve rsed during registra-
tion, the data up to that point is reset, so
perform the registrati on procedure again
from the beginning.
●In the following situations, ID code regis-
tration will not be started or was not com-
pleted properly and the system will not
operate properly. Perform the ID code
registration procedure again.
• If, when attempting to start ID code regis-
tration, the tire pressure warning light
does not blink slowly 3 times.
• If, when the vehicle has been driven for
about 20 minutes after performing ID
code registration, the tire pressure warn-
ing light blinks for approximately 1 minute
and then illuminates.
●If ID code registration cannot be com-
pleted after performing the above proce-
dure, contact your Lexus dealer.
The recommended cold tire inflation
pressure and tire size are displayed on
the tire and loading information label.
( P.399)
Tire valve
Tire inflation pressure
Checking the specified tire infla-
tion pressure
Inspection and adjustment pro-
cedure
A