suspension LEXUS LS430 2005 Owners Manual

GAUGES, METERS AND SERVICE REMINDER INDICATORS
101
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If the smart key system determines that the battery
voltage is low (2V to 3V) when the ignition is turned off
more than 20 minutes after turned on, the master warning
light flashes, a warning tone sounds and the above
message appears for 5 seconds.
If the above message appears, the battery needs to be
replaced. Although you can replace the battery referring to
“Replacing the battery (Type A)” on page 42, we recommend
you have it replaced by your Lexus dealer as it is easy to be
scratched.
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The above message appears when the high mode in the
electronically modulated air suspension is selected.
However, if the system fails , the master warning light
comes on, a warning tone also sounds and the above
message appears.
Although it is no problem to continue driving, have your vehicle
checked by your Lexus dealer as soon as possible.
w285
If the sensor of the Lexus park assist system is
malfunctioning or a cable is broken when the Lexus park
assist system is on, the master warning light comes on, a
warning tone sounds, the malfunctioning sensor flashes
and the above message appears.
The flashing sensor does not operate properly. Although it is
no problem to continue driving, have your vehicle checked by
your Lexus dealer as soon as possible.
w286
If icicles, snowflakes or mud gets on the sensor of the
Lexus park assist system or it is frozen when the Lexus
park assist system is on, the sensor not be able to detect
an obstacle flashes and the above message appears.
Remove the foreign matter or deice the sensor. If the message
does not appear after cleaning, the system is operating
properly.

OCCUPANT RESTRAINT SYSTEMS
177
When the seat belt pretensioners are activated, an operating
noise
may be heard and a small amount of non −toxic gas may
be released. This does not indicate that a fire is occurring. This
gas is normally harmless.
Once the seat belt pretensioners have been activated, the seat
belt retractors remain locked.
CAUTION
Do not modify, remove, strike or open the seat belt
pretensioner assemblies, airbag sensor or surrounding
area or wiring. Failure to follow these instructions may
prevent the seat belt pretensioners from activating
correctly, cause sudden operation of the system or
disable the system, which could result in death or
serious injury. Consult your Lexus dealer about any
repair and modification.
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the seat belt
pretensioners in some cases.
 Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player.
 Repairs on or near the seat belt retractor assemblies.
 Modification of the suspension system.
 Modification of the front end structure.
 Attachment of a grille guard (bull bar, kangaroo bar,
etc.), snowplow, winches or any other equipment to
the front end.
 Repairs made on or near the front fenders, front end
structure or console.

OCCUPANT RESTRAINT SYSTEMS
187
16L759
Do not attach any heavy, sharp or hard objects such
as keys or accessories to the ignition key. The
objects may restrict the SRS knee airbag inflation or
be thrust into the driver’s seat area by the force of the
deploying airbag, causing a danger.
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the SRS front airbag
system in some cases.
 Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player.
 Modification of the suspension system.
 Modification of the front end structure.
 Attachment of a grille guard (bull bar, kangaroo bar,
etc.), snowplow, winches or any other equipment to
the front end.
 Repairs made on or near the front fenders, front end
structure, console, steering column, steering wheel,
lower portion of instrument panel or dashboard near
the front passenger airbag.

OCCUPANT RESTRAINT SYSTEMS
197
NOTICE
Do not perform any of the following changes without
consulting your Lexus dealer. Such changes can
interfere with proper operation of the SRS side airbag
and curtain shield airbag system in some cases.
Installation of electronic devices such as a mobile
twoway radio, cassette tape player or CD player.
 Modification of the suspension system.
 Modification of the structure of the passenger
compartment.
 Repairs made on or near the console or front seat.
16L330b
The indicator comes on when the ignition switch is turned
to the “ON” position. It goes off after about 6 seconds.
This means the SRS side airbags and curtain shield
airbags are operating properly.
This warning light system monitors the airbag sensor
assembly, front airba g sensors, side and curtain shield airbag
sensor assemblies, curtain shield airbag sensor assemblies,
driver’s seat position sensor, driver’s seat belt buckle switch,
occupant detection sensor, front passenger’s seat belt buckle
switch, seat belt pretensioner assemblies, inflators, warning
light, interconnecting wiring and power sources. (For details,
see “Service reminder indicators and warning buzzers” on
page 82.)

SECTION 3 – 1
295
STARTING AND DRIVING
Starting and driving
Three−way catalytic converters296
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine exhaust caution 297
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Before starting the engine 298
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Smart ignition system with steering lock 298
. . . . . . . . . . . . . . . . . . . . .
Ignition switch with steering lock 301
. . . . . . . . . . . . . . . . . . . . . . . . . . .
Parking brake 304
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
How to start the engine 304
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic transmission 305
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electronic throttle control system 315
. . . . . . . . . . . . . . . . . . . . . . . . . . .
Lexus park assist system 316
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear view monitor system 323
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cruise control 326
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
Dynamic radar/laser cruise control 329
. . . . . . . . . . . . . . . . . . . . . . . . .
Electronically modulated air suspension 360
. . . . . . . . . . . . . . . . . . . . .
Traction control system 362
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vehicle stability control system 364
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake system 366
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
Tire pressure warning system 370
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake pad wear limit indicators 373
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pre−collision safety system 374
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STARTING AND DRIVING
360
ELECTRONICALLY MODULATEDAIR SUSPENSION
This electronically modulated air suspension adjusts the
damping effect on the shock absorbers and the vehicle
height. This adjustment is automatically made in
response to the driving conditions to provide good riding
comfort and stability in all driving conditions.
(a) Vehicle height adjustment
31L343
 1High position 2Normal position
This system maintains a stable vehicle height, regardless
of occupants and luggage weight. Select either of the
following modes using a selector switch. Normal mode:
Suitable for driving on roads with a normal
surface.
High mode: Suitable for driving on rough roads which are
unsurfaced or continually bumpy.
The damping effect is set slightly firmer in the high mode. So
you may feel the vibration of the vehicle compared to in the
normal mode. However, this does not mean a malfunction in
the system. We recommend you use a normal mode in normal
driving.
To change the mode, push the selector switch.
Normal mode:
The vehicle height remains at normal height at all driving
speeds.
High mode:
The vehicle height switches between the following two vehicle
heights according to the driving conditions:
Vehicle height
Driving condition
NormalMedium and high speed driving
HighLow speed driving

STARTING AND DRIVING
374
PRECOLLISION SAFETY SYSTEM
(Vehicles with dynamic radar cruise control)
When the precollision safety system detects what it
perceives to be an unavoidable collision, the front seat
belts are quickly drawn back by the retractors
(precollision seat belts) and more powerful braking is
applied according to the amount of pedal depression to
help reduce injury to the occupants and damage to the
vehicle body. In addition, the electronically modulated air
suspension works to help regulate the vehicle not to pitch
forward so much.
Precollision sensor
The millimeter wave radar sensor detects vehicles or
objects near or on the road your vehicle is traveling and
determines the possibility of a collision based on the
object position, vehicle speeds and the course you are
traveling.
The pre −collision sensor will operate in the following
conditions:
 When the ignition switch is turned on.
 When the vehicle speed is about 5 km/h (3 mph) or over.
(The pre−collision safety system does not work with the
vehicle stopped.)
31L359a
 1
Millimeter wave grille cover
2Millimeter wave radar sensor
The millimeter wave radar sensor is installed in the front grille
of the hood.
The millimeter wave radar sensor cannot detect plastic objects
such as pylons, and may not detect people, animals, bicycles,
motor cycles, trees, snowbanks, etc. as objects with which
your vehicle may collide.

STARTING AND DRIVING
376
Precollision brake assist system
When the precollision sensor detects an object or
vehicle with which your vehicle might collide, and
determines that a collision may be unavoidable,
depressing the brake pedal provides more powerful
braking according to the amount of pedal depression.
The pre−collision brake assist system will operate in the
following conditions:
 When the ignition switch is turned on.
 When the approaching speed in regard to the object or the
vehicle exceeds about 30 km/h (18 mph).
 When the brake pedal is depressed.
If the brake pedal is kept depressed before the sensor’s
determination of unavoidable collision, the pre −collision brake
assist system will operate soon after the sensor’s
determination.
Electronically modulated air suspension
control
When the precollision sensor detects an object or
vehicle with which your vehicle may collide, and
determines that a collision may be unavoidable, the
electronically modulated air suspension adjusts the
damping effect on the shock absorbers and regulates the
vehicle not to pitch forward so much.
The electronically modulated air suspension will operate in the
following conditions:
 When the ignition switch is turned on.
 When the vehicle speed is about 5 km/h (3 mph) or over.
 When the approaching speed in regard to the object or the
vehicle exceeds about 30 km/h (18 mph).

DRIVING TIPS
389
Tires
Ensure that your vehicle’s tires are properly inflated. Adjust
the tire inflation pressure to the recommended cold tire
inflation pressure indicated below:
Tire inflation pressure, kPa (kgf/cm
2 or bar, psi)
P225/55R17 95H Front 220 (2.2, 32) Rear 220 (2.2, 32)
245/45R18 96W Front 230 (2.3, 33) Rear 230 (2.3, 33)
P245/45R18 96V Front 230 (2.3, 33) Rear 230 (2.3, 33)
 The trailer tires should be inflated to the pressure
recommended by the trailer manufacturer in respect to the
total trailer weight.
Trailer lights
 Trailer lights must comply with federal, state/provincial and
local regulations. See your local recreational vehicle dealer
or rental agency for the correct type of wiring and relays for
your trailer. Check for correct operation of the turn signals
and stop lights each time you hitch up. Direct splicing may
damage your vehicle’s electrical system and cause a
malfunction of your lights.
Breakin schedule
 Lexus recommends that you do not tow a trailer with a new
vehicle or a vehicle with any new power train component
(engine, transmission, differential, wheel bearing, etc.) for
the first 800 km (500 miles) of driving.
Maintenance
 If you tow a trailer, your vehicle will require more frequent
maintenance due to the additional load. For this
information, please refer to the scheduled maintenance
information in the “Owner’s Manual Supplement /
Scheduled Maintenance”.
 Retighten all fixing bolts of the towing ball and bracket after
approximately 1000 km (600 miles) of trailer driving.
Pretowing safety check
 Check that your vehicle remains level when a loaded or
unloaded trailer is hitched. Do not drive if the vehicle has
an abnormal nose −up or nose− down condition, and check
for improper tongue load, overload, worn suspension or
other possible causes.
 Make sure the trailer cargo is securely loaded so that it
cannot shift.
 Check that your rear view mirrors conform to any federal,
state/provincial or local regulations. If they do not, install
required rear view mirrors appropriate for towing purposes.

MAINTENANCE
430
Tire rotation
Rotate the tires according to the maintenance schedule.
(For scheduled maintenance information, please refer to
the “Owner’s Manual Supplement / Scheduled
Maintenance”.) See page 480 for additional information.DOES YOUR VEHICLE NEED
REPAIRING?
Be on the alert for changes in performance and sounds, and
visual tip −offs that indicate service is needed. Some important
clues are:
 Engine missing, stumbling, or pinging
 Appreciable loss of power
 Strange engine noises
 A fluid leak under the vehicle (However, water dripping from
the air conditioning after use is normal.)
 Change in exhaust sound (This may indicate a dangerous
carbon monoxide leak. Drive with the windows open and
have the exhaust system checked immediately.)
 Flat−looking tires, excessive tire squeal when cornering,
uneven tire wear
 Vehicle pulls to one side when driving straight on a level
road
 Strange noises related to suspension movement
 Loss of brake effectiveness, spongy feeling brake pedal,
pedal almost touches floors, vehicle pulls to one side when
braking
 Engine coolant temperature continually higher than normal
If you notice any of these clues, take your vehicle to your Lexus
dealer as soon as possible. It probably needs adjustment or
repair.