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Brake assist system
If you slam the brakes on such as in an emergency or
apply the brakes more firmly than usual such as when
descending the hill with the designated number of
occupants in the vehicle, the brake assist system
provides more powerful braking.
If you slam the brakes on or apply the brakes more firmly, more
powerful braking will be applied. At this time, you may hear a
sound in the engine compartment and feel the vibrations of the
brake pedal. This does not indicate a malfunction.
The brake assist system becomes operative after the vehicle
has accelerated to a speed in excess of approximately 10 km/h
(6 mph). It stops operating when the vehicle decelerates to a
speed below approximately 5 km/h (3 mph).
For an explanation of this system’s warning light, see “ABS
warning light” on page 81 or 460.
TIRE PRESSURE WARNING SYSTEM
The tire pressure warning system is designed to provide
warning when tire inflation pressure is critically low while
the vehicle is moving. The low tire pressure warning light
comes on to inform you that such low tire pressure may
hamper driving.
This system is not designed to operate when the vehicle is
stopped. Therefore, check the tire inflation pressure regularly.
The recommended cold tire inflation pressure, tire size and the
vehicle capacity weight are on the tire and loading information
label. (For instructions, see “Checking tire inflation pressure”
on page 570.)
Installed tires should be of the specified size. They should be
of the same size and construction. If tires other than the
specified size are used, or if tires of different sizes or
constructions are mixed, the tire pressure warning system will
not function properly.
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Low tire pressure warning light
This light comes on when the ignition key is turned to the “ON”
position. It goes off after a few seconds. This indicates that the
tire pressure warning system is functioning properly.
If the low tire pressure warning light comes on or blinks
while driving, do the following.
If the warning light comes on: The tire pressure is critically
low. Adjust the tire inflation pressure to the specified level
as soon as possible. (See “Tires and wheels” on page 566.)
Once the ignition switch is turned off, the warning light also
goes off. If the light comes on again when the vehicle is started
after adjusting tire inflation pressure to the specified level, have
the system checked at your Lexus dealer. If you have a flat tire, replace it with the spare tire. For details,
see “If you have a flat tire” on page 500.
If the warning light blinks once every second: The low
tire pressure warning system may be malfunctioning.
Contact your Lexus dealer.
If the warning light blinks twice every second: The low
tire pressure warning system needs to be initialized. Reset
the system with the tire pressure warning system reset
switch. (To reset the system, see “Tire pressure warning
system reset switch”.)
The tire pressure warning system does not function
properly under certain circumstances. In the following
cases, the low tire pressure warning light may not come
on even if the tire inflation pressure is low, or it may come
on when the tire inflation pressure is actually normal.
A compact spare tire, snow tires, or tire chains are used.
The tire inflation pressure is excessively higher than
specified, or tire inflation pressure suddenly drops due to
bursting or other causes.
The vehicle is driven on a slippery road surface such as
rough or frozen roads.
The vehicle speed is less than 30 km/h (19 mph) or more
than 100 km/h (62 mph), and the driving duration is less than
5 minutes.
The tires differ in tread pattern or manufacturer.
The tires are not the specified size.
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The tread wear is very different among the installed tires.
Rapid acceleration/deceleration or sharp turns is continue.
Towing a trailer.
The loading is over the limit or imbalanced.
Initialization was not performed correctly after replacing or
rotating tires or wheels.
The outside temperature is below 0 C (32F) or above
40 C (104 F).
CAUTION
When the tire pressure warning light comes on, observe
the following instructions:
Adjust the tire inflation pressure to the specified level
as soon as possible.
Avoid abrupt steering wheel maneuvering and
braking when the tire pressure warning light comes
on. If the vehicle tires deteriorate, you could lose
control of the steering wheel or the brakes, causing
death or serious injury.
Tire pressure warning system reset switch
The tire pressure warning system need to be initialized in
the following conditions:
When the low tire pressure warning light blinks twice
every second
After replacing or rotating tires or wheels
When initializing the system, the present tire condition is
stored as a standard.
To initialize the system, perform the following:
1. Park the vehicle at a safe place and apply the parking brake.
Stop the engine.
2. Adjust the pressure of all the installed tires to the specified
level. (See “Tires and wheels” on page 566.)
3. Turn the ignition key to “ON”.
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4. With the vehicle stopped, push the reset switch on the left
lower instrument panel and hold it until the low tire pressure
warning light blinks three times.
Initialization is
completed after driving at the speeds of 30 km/h
(19 mph) or over for about a few hours total, when the tire
pressure warning system detects the normal tire pressure. If
the following driving conditions are satisfied, initialization will
be completed in about one hour.
Vehicle speed varies between 30 km/h (19 mph) and 80
km/h (50 mph)
Normal road surface
When the warning light blinks twice every second while driving,
you may be unable to reset the system. In this case, set the
system again according to the above procedure.
Do not push the reset switch without adjusting the tire inflation
pressure to the specified level. Otherwise, the low tire
pressure warning light may not come on even if the tire
pressure is low, or it may come on when the tire inflation
pressure is actually normal.
If you push the reset switch while the vehicle is moving,
initialization is not performed.
If the low tire pressure warning light does not blink when you
push and hold the reset switch, have the low pressure warning
system checked at your Lexus dealer.
BRAKE PAD WEAR LIMIT INDICATORS
The brake pad wear limit indicators on your disc brakes
give a warning noise when the brake pads are worn to the
extent that replacement is required.
If you hear a squealing or scraping noise while driving, have the
brake pads checked and replaced by your Lexus dealer as
soon as possible. Expensive rotor damage can result if the
pads are not replaced when needed.
MAINTENANCE
530Battery
Check the battery condition by the indicator color. See page
601 for additional information.
Brake fluid level
Make sure the brake fluid level is correct. See page 568 for
additional information.
Engine oil level
Check the level on the dipstick with the engine turned off and
the vehicle parked on a level spot. See page 556 for
additional
information.
Power steering fluid level
Check the level through the reservoir. The level should be in
the “HOT” or “COLD” range depending on the fluid
temperature. See page 569 for additional information.
Exhaust system
If you notice any change in the sound of the exhaust or smell
exhaust fumes, have the cause located and corrected
immediately. (See “Engine exhaust caution” on page 384.)
Vehicle interior
Items listed below should be checked regularly, e.g. while
performing periodic services, cleaning the vehicle, etc.
Lights
Make sure the headlight, stop lights, tail lights, turn signal
lights, and other lights are working. Check headlight aim.
Service reminder indicators and warning buzzers
Check that all service reminder indicators and warning buzzers
function properly.
Steering wheel
Check that it has the specified free play. Be alert for changes
in steering condition, such as hard steering, excessive free
play or strange noise.
Seats
Check that all front seat controls such as seat adjusters,
seatback recliner, etc., operate smoothly. Check that the head
restraints move up and down smoothly and that the locks hold
securely in any latched position. For folding −down rear
seatbacks, check that the latches lock securely.
Seat belts
Check that the seat belt system such as buckles, retractors
and anchors operate properly and smoothly. Make sure the
belt webbing is not cut, frayed, worn or damaged.
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Uniform tire quality grading
This information has been prepared in accordance
with regulations issued by the National Highway
Traffic Safety Administration of the U.S.
Department of Transportation. It provides the
purchasers and/or prospective purchasers of
Lexus vehicles with information on uniform tire
quality grading.
Your Lexus dealer will help answer any questions
you may have as you read this information.
DOT quality grades — All passenger vehicle tires
must conform to Federal Safety Requirements in
addition to these grades. Quality grades can be
found where applicable on the tire sidewall
between tread shoulder and maximum section
width. For example: Treadwear 200 Traction AA
Temperature ATreadwear
— The treadwear grade is a comparative
rating based on the wear rate of the tire when tested
under controlled conditions on a specified government
test course. For example, a tire graded 150 would
wear one and a half (1 — 1/2) times as well on the
government course as a tire graded 100. The relative
performance of tires depends upon the actual
conditions of their use, however, and may depart
significantly from the norm due to variations in driving
habits, service practices and differences in road
characteristics and climate.
Traction AA, A, B, C — The traction grades, from
highest to lowest, are AA, A, B and C, and they
represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is
based on braking (straight ahead) traction tests and
does not include cornering (turning) traction.
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Temperature A, B, C — The temperature grades are
A (the highest), B, and C, representing the tire’s
resistance to the generation of heat and its ability to
dissipate heat when tested under controlled conditions
on a specified indoor laboratory test wheel. Sustained
high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The
grade C corresponds to a level of performance which
all passenger car tires must meet under the Federal
Motor Vehicle Safety Standard No. 109. Grades B
and A represent higher levels of performance on the
laboratory test wheel than the minimum required by
law.
Warning: The temperature grades for this tire are
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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ROTATING TIRES
To equalize the wear and help extend tire life,
Lexus recommends that you rotate your tires
according to the maintenance schedule. (For
scheduled maintenance information, please refer
to the “Owner’s Manual Supplement / Scheduled
Maintenance”.) However, the most appropriate
timing for tire rotation may vary according to your
driving habits and road surface conditions.
The wheel assemblies must be rotated as illustrated
above.When rotating tires, check for uneven wear and
damage. Abnormal wear is usually caused by
incorrect tire pressure, improper wheel alignment,
out−of balance wheels, or severe braking.
Before storing radial, snow or studded tires, mark the
direction of rotation and be sure to install them in the
same direction when using them again. Tires should
be stored in a cool dry place.
Initial adjustment of the tire pressure warning
system is necessary after you have rotated your
tires. See “Tire pressure warning system” on page
462.