2006 Lexus GS430 stop start

STARTING AND DRIVING
433
When the slip indicator light comes on, and the message
“CHECK ECB*” appears
on the multi−information display, the
vehicle dynamics integrated management does not operate.
Have your vehicle checked by your Lexus dealer as soon as
possible.
*: Electronically Controlled Brake System
In addition, when the master warning light comes on, and the
message “CHECK VGRS” or “CHECK P/S” appears on the
multi−information display, the system will not be temporarily
functioning. Although it is no problem in driving as usual, have
your vehicle checked by your Lexus dealer as soon as
possible.
CAUTION
Do not overestimate the vehicle dynamics integrated
management. Even when this management is
functional, there is a limit to vehicle stability, and
irresponsible driving may lead to an accident. When
driving, you should always pay attention to your speed
and keep a safe distance between your vehicle and the
vehicle in front.
BRAKE SYSTEM
GS430:
This brake system has 3 independent hydraulic circuits. If any
circuits should fail, the other will still work. However, the pedal
will be harder to press, and your stopping distance will
increase. Also, the brake system warning light (red) may come
on.
GS300:
The tandem master cylinder brake system is a hydraulic
system with two separate sub −systems. If either sub −system
should fail, the other will still work. However, the pedal will be
harder to press, and your stopping distance will increase. Also,
the brake system warning light (red) may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake actuator (GS430)
The brake actuator uses brake fluid pressurized by the pump
to power −assist the brakes. If the brake actuator fails during
driving, the brake system warning light (red) comes on and the
buzzer sounds continuously. In this case, the brakes may not
work properly. If the brake system warning light comes on,
immediately stop your vehicle and contact your Lexus dealer.

STARTING AND DRIVING
434Any of the following conditions may occur, but does not
indicate a malfunction:

The brake system warning light (red) may stay on for about
60 seconds after the engine is started. It is normal if the light
turns off after a while.
 Depressing the brake pedal repeatedly may turn on the
brake system warning light (red). It is normal if the light goes
out after a few seconds.
 You may hear a small sound in the engine compartment
after the engine is started or the brake pedal is depressed
repeatedly. This is a pump pulsating sound of the brake
system.
CAUTION
Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your reserved brake
fluid pressure.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will increase.
Brake booster (GS300)
The brake booster uses engine vacuum to power −assist the
brakes. If the engine should quit while you are driving, you can
bring the vehicle to a stop with normal pedal pressure. There
is enough reserved vacuum for one or two stops but no more!
CAUTION
 Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your reserved
vacuum.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will increase.
Antilock brake system
The antilock brake system is designed to automatically
help prevent lockup of the wheels during a sudden
braking or braking on slippery road surfaces. This assists
in providing directional stability and steering
performance of the vehicle under these circumstances.
Effective way to press the ABS brake pedal: When the
anti−lock brake system function is in action, you may feel the
brake pedal pulsating and hear a noise. In this situation, to
let the anti−lock brake system work for you, just hold the
brake pedal down more firmly. Do not pump the brake in a
panic stop. This will result in reduced braking performance.

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The anti
−lock brake 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).
Depressing the brake pedal on slippery road surfaces such as
on a manhole cover, a steel plate at a construction site, joints
in a bridge, etc. on a rainy day tends to activate the anti −lock
brake system.
You may hear a click or motor sound in the engine
compartment for a few seconds when the engine is started or
just after the vehicle begins to move. This means that the
anti−lock brake system is in the self− check mode, and does not
indicate a malfunction.
When the antilock brake system is activated, the
following conditions may occur. They do not indicate a
malfunction of the system:
 You may hear the anti− lock brake system operating and feel
the brake pedal pulsating and the vibrations of the vehicle
body and steering wheel. You may also hear the motor
sound in the engine compartment even after the vehicle is
stopped.
 At the end of the anti−lock brake system activation, the
brake pedal may move a little forward.
CAUTION
Do not overestimate the antilock brake system:
Although the antilock brake system assists in
providing vehicle control, it is still important to drive
with all due care and maintain a moderate speed and
safe distance from the vehicle in front of you, because
there are limits to the vehicle stability and effectiveness
of steering wheel operation even with the antilock
brake system on.
If tire grip performance exceeds its capability, or if
hydroplaning occurs during high speed driving in the
rain, the antilock brake system does not provide
vehicle control.
Antilock brake system is not designed to shorten the
stopping distance: Always drive at a moderate speed
and maintain a safe distance from the vehicle in front of
you. Compared with vehicles without an antilock
brake system, your vehicle may require a longer
stopping distance in the following cases:
 Driving on rough, gravel or snowcovered roads.
 Driving with tire chains installed.
 Driving over the st eps such as the joints on the road.
 Driving on roads where the road surface is pitted or
has other differences in surface height.

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Install all 4 tires of specified size at appropriate
pressure: The antilock brake system detects vehicle
speeds using the speed sensors for respective wheels’
turning speeds. The use of tires other than specified
may fail to detect the accurate turning speed resulting
in a longer stopping distance.“ABS” warning light
G31080
 1 U.S.A. 2Canada
GS430—The light comes on when the engine switch is
selected in “IG −ON” mode. If the anti −lock brake system and
the brake assist system work properly, the light turns off in a
few seconds after the engine is started.
GS300—The light comes on for a few seconds when the
engine switch is selected in “IG −ON” mode. It indicates the
anti− lock brake system and the brake assist system work
properly.
If either system malfunctions, the light comes on again.
When the “ABS” warning light is on, the anti− lock brake system
and the brake assist system do not operate, but the brake
system still operates conventionally.

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If any of the following conditions occur, this indicates a
malfunction
somewhere in the components monitored by
the warning light system. Contact your Lexus dealer as
soon as possible to service the vehicle.
 The light does not come on when engine switch is selected
in “IG− ON” mode.
 The light remains on after the engine is started (GS430), or
remains on a few seconds after the engine switch is
selected in “IG −ON” mode (GS300).
 The light comes on while you are driving.
A warning light turning on briefly during operation does not
indicate a problem.
CAUTION
If the “ABS” warning light remains on together with the
brake system warning light (red), immediately stop your
vehicle at a safe place and contact your Lexus dealer.
In this case, not only the antilock brake system will fail
but also the vehicle will become extremely unstable
during braking.
GS430 only—Either of the following conditions may
occur, but does not indicate a malfunction:
 The light may stay on for about 60 seconds after the engine
is started. It is normal if it turns off after a while.
 Depressing the brake pedal repeatedly may turn on the
light. It is normal if it turns off after a few seconds.
Drumindisc 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.
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 80 or 436.

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BRAKE PAD WEAR LIMITINDICATORS
G31006
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.
GS430 front brake only—
The high brake performance is achieved by proper wear of
brake pads and discs. As a result, the brake discs may wear
earlier than the ones on the conventional brake system.
When brake pads are replaced, brake disc thickness is
required to be measured.
It is dangerous to continue driving when brake pads and discs
have exceeded the wear limit.
ELECTRIC POWER STEERING SYSTEM
The electric power steering system, using an electric
motor, assists the turning of the steering wheel.
In the following cases, you may feel the steering becomes
heavy. However, the electric power steering system
warning light does not come on. (Because it is not a
malfunction.)
When maneuvering or turning frequently over a long time, the
power steering effect will be reduced to prevent the system
from overheating. A void turning the steering wheel, or stop the
vehicle. The system will become cool in about 10 minutes.
NOTICE
Frequent maneuvering and turning over a long time may
cause damage to the system in which the mechanism
prevents overheating of the electric power steering
system.
When the battery is discharged, check the battery’s condition.
If necessary, recharge or replace the battery. For details, see
“Checking battery condition” on page 581.

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Display
Indicator
statusMeaningsDo this
Tire pressure
warning lightONTire inflation
pressure is
lowAdjust the tireinflation
pressure
Multi
information
displayLOW TIRE
(PRESSURE)
Tire pressure
warning lightBlinkingTire pressure
warning
system
malfunctionHave the
system
checked at
your Lexus
dealer
Multi
information
displayCHECK
(TIRE
PRES-
SURE)
SYSTEM
CAUTION
If the tire pressure warning light comes on, be sure to
observe the following precautions. Failure to do so
could cause loss of vehicle control and result in death
or serious injury.
Vehicles with runflat tires:
 Decelerate to the lowest appropriate speed as soon
as possible. Do not drive over 90 km/h (55 mph).
 Check and adjust the tire inflation pressure
immediately.
 If the tire pressure warning light comes on even after
tire inflation pressure adjustment, it is probable that
you have a flat tire. Have the tire replaced by the
nearest Lexus dealer.
 Avoid abrupt maneuvering and braking. If the vehicle
tires deteriorate, you could lose control of the
steering wheel or the brakes.
Vehicles with standard tires:
 Stop your vehicle in a safe place as soon as possible.
Adjust the tire inflation pressure immediately.
 If the tire pressure warning light comes on even after
tire inflation pressure adjustment, it is probable that
you have a flat tire. Check the tires. If the tire is flat,
change to the spare tire and have the flat tire repaired
by the nearest Lexus dealer.
 Avoid abrupt maneuvering and braking. If the vehicle
tires deteriorate, you could lose control of the
steering wheel or the brakes.

STARTING AND DRIVING
442The tire pressure warning light may turn on due to natural
causes such as natural air l
eaks or tire inflation pressure
changes caused by temperature. In this case, adjusting the
tire inflation pressure will turn off the light after a few minutes.
Pushing the tire pressure warning reset switch should not turn
off the tire pressure warning light. Adjusting the tire inflation
pressure will turn off the light.
The compact spare tire is not equipped with the tire pressure
warning valve and transmitter. If a tire goes flat, the warning
light will not turn off even though the flat tire is replaced with the
spare tire. Replace the spare tire with the repaired tire and
adjust the proper tire inflation pressure. The tire pressure
warning light will turn off after a few minutes.
CAUTION
Each tire, including the spare (if provided), should be
checked m onthly when cold and inflated to the inflation
pressure recommended by the vehicle manufacturer on
the vehicle placard or tire inflation pressure label (tire
and load information label). (If your vehicle has tires of
a different size than the size indicated on the vehicle
placard or tire inflation pressure label (tire and load
information label), you should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system
(TPMS–tire pressure warning system) that illuminates a
low tire pressure telltale (tire pressure warning light)
when one or more of your tires is significantly
underinflated. Accordingly, when the low tire pressure
telltale (tire pressure warning light) illuminates, you
should stop and check your tires as soon as possible,
and inflate them to the proper pressure. Driving on a
significantly underinflated tire causes the tire to
overheat and can lead to tire failure. Underinflation
also reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.