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Brake assist system
When you slam the brakes on, the brake assist system
judges as an emergency stop and provides more powerful
braking for a driver who cannot hold down the brake pedal
firmly.
When you slam the brakes on, 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).
The brake assist system may not work for about 60 seconds
after the engine is started.
For an explanation of this system’s warning light, see “ABS
warning light” on page 57.
Drum in disc type parking brake system
Your vehicle has a drum−in−disc type parking brake system.
This type of brake system needs bedding −down of the brake
shoes periodically or whenever the parking brake shoes and/or
drums are replaced.
Have your Lexus dealer perform the bedding −down.
TIRE PRESSURE WARNING
SYSTEM
The tire pressure warning system is designed to provide
warning when tire inflation pressure of one or more of
your tires (including the spare tire) is low. The low tire
pressure warning light comes on to inform you that low
tire inflation pressure may hamper driving.
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.
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388If the low tire pressure warning light comes on or blinks,
do the following.
If the warning light comes on:
Stop your
vehicle in a safe place as soon as possible and
check that the inflation pressure of all tires (including the
spare tire) is as specified on the tire and loading
information label. (See “Checking tire inflation pressure”
on page 523.) If the warning light comes on even after tire
inflation pressure adjustment, you may have a flat tire. If
you have a flat tire, replace it with the spare tire. For
details, see “If you have a flat tire” on page 432.
The warning light goes off a few minutes after air is put into the
deflated tire.
This warning light may turn on due to natural causes such as
natural air leaks or tire pressure changes caused by
temperature. In this case, adjusting the tire pressure will turn
off the warning light.
CAUTION
When the low tire pressure warning light comes on,
observe the following instructions:
Depending on the conditions, reduce to an
appropriate speed as soon as possible.
Adjust the tire pressure to the specified level as soon
as possible.
Avoid abrupt steering wheel maneuvering and
braking. Tire deterioration may reduce steering
wheel control and brake effectiveness. This may lead
to serious injury or death.
The tire pressure warning system may not activate
immediately if sudden bursts of air leakage occur.
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NOTICE
Do not use liquid sealants for a flat tire as air pressure
sensors will be damaged.
When the tires must be repaired or replaced, have
them repaired or replaced by the nearest Lexus
dealer or authorized tire dealer. The tire pressure
sensors will be affected by the installation or removal
of tires.
The tire pressure warning system is not to be used as
a substitute for regular inspections. Be sure to check
the air pressure in the tires on a regular basis.
When the tires must be replaced, replace the
grommets for air pressure sensors as well.
If the warning light blinks:
The tire pressure warning system may be malfunctioning.
Contact your Lexus dealer.
System malfunction
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.
Electric devices or facilities using similar radio wave
frequencies are nearby.
A radio set to similar frequencies is in use.
A lot of snow or ice covers the vehicle, in particular, around
the wheels or wheel housings.
The tires are not equipped with an air pressure sensor.
Tire chains are used.
Non −genuine Lexus wheels are used.
Although the tires are equipped with air pressure sensors,
the selector switch (see page 393.) is set to other tire setting.
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