2006 Lexus GS430 warning

IN CASE OF AN EMERGENCY
471
Compact spare tire
G40025
The compact spare tire is designed for temporary
emergency use only.
The compact spare tire is identified by the distinctive
wording “TEMPORARY USE ONLY” molded into the
side wall of the tire.
To keep the compact spare tire noticeable, do not hide
the wheel by a wheel cover or such.
The compact spare tire saves space in your luggage
compartment, and its lighter weight helps to improve fuel
economy and permits easier installation in case of a flat
tire. The compact spare tire is not equipped with the tire
pressure sensor
. If tire inflation pressure becomes low,
the tire pressure warning system will not be activated.
Also, if you replace the compact spare tire after the low
tire pressure warning light comes on, the light remains
on.
The compact spare tire can be used many times, if
necessary. It has tread life of up to 4800 km (3000 miles)
depending on road conditions and your driving habits.
When tread wear indicators appear on the tire, replace
the tire. (See “Checking and replacing tires” on page
554.)

MAINTENANCE
494Battery
Your Lexus has a maintenance free battery. You do not have
to add distilled water. For longer life of the battery, however,
see page 571 for additional information.
Brake fluid level
Make sure the brake fluid level is correct. See page 538 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 522 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 341.)
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 ha s 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.
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.

CHASSIS
538
CHECKING BRAKE FLUID
G62010
GS430
G62011
GS300
To check the fluid level, simply look at the seethrough
reservoir. The level should be between the ”MAX” and
”MIN” lines on the tank. It is normal for the brake fluid level to go down slightly as the
brake pads wear or when the fluid level in the accumulator is
high.
If the level is low, take your vehicle to a Lexus dealer as
soon as possible. Do not drive your vehicle if the brake
system warning light (red) is on. Call a Lexus dealer for
assistance.
If the fluid level goes down soon after your vehicle is
serviced, it may indicate a serious mechanical problem.
Have your vehicle checked by your Lexus dealer.
CAUTION
Brake
fluid can harm your hands or eyes. If fluid gets on
your hands or in your eyes, flush the affected area with
clean water immediately. If you still feel uncomfortable
with your hands or eyes, go to the doctor.

CHASSIS
548
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
A
Treadwear − 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.
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.

CHASSIS
552
RUNFLAT TIRES
This vehicle can be equipped with either runflat
tires (RFT) or standard tires. You may continue
driving on the vehicle with runflat tires even if any
tire goes flat. It may be able to run for a maximum
of 160 km (100 miles) at a speed below 90 km/h (55
mph) after the low tire pressure warning light comes
on. When you drive your vehicle after the low tire
pressure warning light comes on, the tire must be
replaced. Do not use the repaired tire.
G63004
A “RFT” or “DSST” mark is molded on the sidewall of the
run−flat tire.
If you cannot distinguish between the standard tire and
run−flat tire, consult Lexus dealer.
If you have a flat tire, you have to take a different action
depending on whether the tires are standard tires or
run−flat tires.
Runflat tires characteristics:
The vehicle with run −flat tires helps you to continue
driving for up to 160 km (100 miles) at the moderate
speed and do not ever exceed 90 km/h (55 mph) even
with a flat tire. After such usage, the tire must be
replaced. If you are not sure, consult your Lexus dealer.
If you have a flat tire, decrease the speed and drive at
lower speed to reduce the extent to which the tire is
damaged.
However, in some conditions (such as at high
temperatures), you could not continue driving for up to
160 km (100 miles).
The use of non−genuine wheels may prohibit optimum
performance.
The run −flat tires equipped on this vehicle are ones
dedicated for GS430/300. Do not use them on another
model.
Do not mix run− flat tires with standard tires.
The tire warranty book covers the detailed information
on run− flat tires. For details, see the tire warranty book.
Tire pressure warning system
The tire pressure warning system is equipped to warn
you of the low tire inflation pressure. For details, see
“Tire pressure warning system” on page 433.

CHASSIS
559
Chain installation
Install the chains on the rear tires as tightly as possible.
Do not use tire chains on the front tires. Retighten chains
after driving 0.5 1.0 km (1/4 1/2 mile).
When installing chains on your tires, carefully follow the
instructions of the chain manufacturer.
CAUTION
Do not exceed 50 km/h (30 mph) or the chain
manufacturer’s recommended speed limit,
whichever is lower.
 Drive carefully avoiding bumps, holes, and sharp
turns, which may cause the vehicle to bounce.
 Avoid sharp turns or lockedwheel braking, as use of
chains may adversely affect vehicle handling.
 When driving with chains installed, be sure to drive
carefully. Slow down before entering curves to avoid
losing control of the vehicle. Otherwise an accident
may occur.
NOTICE
When the snow tires must be repaired or replaced,
have them repaired or replaced by Lexus dealer or
authorized tire dealer. The tire pressure sensor will
be affected by the installation or removal of snow
tires.
 When the snow tires must be replaced, replace the
grommets for tire pressure sensors as well.
 Do not attempt to use a tire chain on the compact
spare tire, as it may result in damage to the vehicle as
well as the tire.
If the chains are installed, the tire pressure warning
system may not operate properly. See “Tire pressure
warning system” on page 433.

CHASSIS
560
REPLACING WHEELS
As you might have difficulty in identifying a flat or deflated
tire, a tire pressure warning system is provided on this
vehicle.
When replacing the wheels, be sure to install tire pressure
sensors on the wheels.
There are 2 ways to set up the tire pressure sensors.
a. Remove the sensor from the old wheel and install it to the
new wheel.
b. Use a new wheel and sensor.You have to register an ID code for a new sensor. Up to 2
sets of codes can be registered. As one ID for the originally
installed sensor is registered at “MAIN” of the selector
switch, use the “2nd” position to register an ID for the new
sensor.
You do not need to re −register the ID code for any other
replacements. For the use of the originally installed tires,
put the selector switch at “MAIN” and for the use of tires
purchased later, put the switch at “2nd”. For the sensor
selector switch, see page 442.
CAUTION
 Have the tires, wheels or sensors replaced and ID
codes registered by Lexus dealer. If you need
sensors, purchase from Lexus dealer.
 The sensor nuts should always be tightened to a
torque of 4 N·m (0.4 kgf·m, 2.9 ft·lbf).
 The use of nongenuine wheels will cause the tire
pressure sensor to transmit the electronic code in
different manner, resulting in the failure of the
system.
When to replace your wheels
If you have wheel damage such as bending, cracks or
heavy corrosion, the wheel should be replaced.
If you fail to replace a damaged wheel, the tire may slip off the
wheel or cause loss of handling control.
Replacement with used wheels is not recommended as they
may have been subjected to rough treatment or high mileage
and could fail without warning. Also, bent wheels which have
been straightened may have hidden structural damage and
therefore should not be used. Never use an inner tube in a
leaking wheel which is designed for a tubeless tire.

ELECTRICAL COMPONENTS
566
No.FUSEAMPERECIRCUIT
1 STR LOCK25Steering lock system
2 SECURITY7.5Smart access system with
push−button start
3 TI &TE20Power tilt and telescopic
steering wheel, Multiplex
communication system
4 AM17.5Starting system
5 STOP SW7.5
Stop/tail lights, Multi− port fuel
injection system/sequential
multiport fuel injection system,
Starting system, Electronic
control brake system, Vehicle
stability control system, Shift
lock system
6 OBD7.5On− board diagnosis system
7 FR P/SEAT
RH30Power seat system
8 AIR SUS20Electronic modulated
suspension
9 PWR
OUTLET15Power outlet
10 CIG15Cigarette lighter
11 ACC7.5
Multiplex communication
system, Smart access system
with push− button start, Rear
view monitor system, Audio
system, Air conditioning system
No.FUSEAMPERECIRCUIT
12 IGN10
Multi− port fuel injection
system/sequential multiport fuel
injection system, SRS airbag
system, Stop/tail lights,
Steering lock system, Electronic
control brake system
13 GAUGE7.5Gauges and meters
14 ECUIG
RH10
Power tilt and telescopic
steering wheel, Multiplex
communication system, Smart
access system with
push −button start, Audio
system, Air conditioning
system, Shift lock system, Tire
pressure warning system,
Combination switch
15 FR S/HTR
RH15Seat heater, Heated and
ventilated seats
16 RHIG7.5
Seat heater switches, Front
right door control system, Rear
right door control system,
Capacitor, Combination switch,
Seat belt pretensioners,
Intuitive parking assist
17 AM215Starting system