air suspension lexus LS400 1998 Electrical Components / LEXUS 1998 LS400 OWNER'S MANUAL (OM50498U)

COMFORT ADJUSTMENT
96
NOTICE
Do not perform any of the following changes without consulting
your Lexus dealer. Such changes can interfere with proper
operation of the SRS in some cases.
Installation of electronic items such as a mobile twoway
radio, cassette tape player or compact disc player.
Modification of the suspension system.
Modification of the front end structure and side structure of
the passenger compartment.
Attachment of a grille guard (bull bar, kangaroo bar, etc.),
snow plow, 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,
dashboard near the front passenger airbag, front seats or seat
belt assembly.
16L136-2
This SRS has an indicator to inform the driver of operating problems.
If either of the following conditions occurs, this indicates a
malfunction of the airbags and/or seat belt pretensioners. Even if the
seat belt pretensioners should fail, the seat belts will operate
conventionally. Contact your Lexus dealer as soon as possible to
service the vehicle.
The light does not come on as described above.
The light stays on or flashes.
The light comes on or starts flashing while driving.
If the light stays on, it indicates that the driver and front passenger
airbags fail. If the light flashes, the side airbags and/or seat belt
pretensioners fail.

SECTION 3 1
154
STARTING AND DRIVING
Starting and driving
Threeway catalytic converter 155. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine exhaust caution 156. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Before starting the engine 157. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ignition switch with steering lock 157. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parking brake 158. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
How to start the engine 159. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic transmission 160. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electronic throttle control system 167. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cruise control 168. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electronically modulated air suspension 171. . . . . . . . . . . . . . . . . . . . . . .
Traction control system 173. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vehicle skid control system 174. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake system 176. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Types of tires 179. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STARTING AND DRIVING
171
Cruise control failure warning
If the ”CRUISE” indicator light in the instrument cluster flashes
when using the cruise control, push the main switch to turn the
system off and then push it again to turn it on.
If any of the following conditions then occurs, there is some trouble
in the cruise control system.
The indicator light does not come on.
The indicator light flashes again.
The indicator light goes out after it comes on.
If this is the case, contact your Lexus dealer and have your Lexus
inspected.
ELECTRONICALLY MODULATED
AIR SUSPENSION
(U.S.A. ONLY)
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
31L015-3
This system maintains a stable vehicle height, regardless of
occupants and luggage weight. You can select one of the
following modes using a selector switch.

STARTING AND DRIVING
174
VEHICLE SKID CONTROL SYSTEM
The vehicle skid control system helps to provide comprehensive
control of the systems such as an antilock brake system,
traction control, engine control, electronically modulated air
suspension, etc. This system automatically controls the output
of the brakes or engine to help prevent the vehicle from skidding
when cornering on a slippery road surface or abrupt steering
wheel operation occurs.
31L0521
Slip indicator light
If the vehicle is going to skid during driving, the slip indicator light
flashes and an alarm sounds.
The vehicle skid control activates when the vehicle speed is about
more than 15 km/h (9 mph).Depressing the brake pedal repeatedly causes a small noise from the
engine compartment. This is a pump pulsating sound of the brake
system and it is not a malfunction.
You may hear a slight clicking noise in the engine compartment for
a few seconds when the engine is started or just after the vehicle is
started. This means that the vehicle skid control is in the selfcheck
mode and does not indicate a malfunction.
31L017-2
You can turn off the vehicle skid control system by pushing the
”VSC OFF” switch. The ”VSC OFF” indicator comes on. At
this time, the traction control system also turns off. You cannot
turn off either one of them. Pushing the ”VSC OFF” switch a
second time turns the system back on and extinguishes the ”VSC
OFF” indicator light.
When you turn the ignition switch on, this system always turns on.

MAINTENANCE
217
DOES YOUR VEHICLE NEED
REPAIRING?
Be on the alert for changes in performance and sounds, and visual
tipoffs 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.)
Flatlooking 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.
CAUTION
Do not continue driving with the vehicle unchecked. It could
result in serious vehicle damage and possibly personal injury.

CHASSIS
247
REPLACING WHEELS
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 damaged wheels, a tire may slip off a wheel or
they may 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.
Wheel selection
When replacing wheels, care should be taken to ensure that they
are equivalent to those removed in load capacity, diameter, rim
width, and offset.
Correct replacement wheels are available at your Lexus dealer.
A wheel of a different size or type may adversely affect handling,
wheel and bearing life, brake cooling, speedometer/odometer
calibration, stopping ability, headlight aim, bumper height, vehicle
ground clearance, and tire or snow chain clearance to the body and
chassis.
ALUMINUM WHEEL
PRECAUTIONS
After driving your vehicle the first 1600 km (1000 miles), check
that the wheel nuts are tight.
If you have rotated, repaired, or changed your tires, check that the
wheel nuts are still tight after driving 1600 km (1000 miles).
When using tire chains, be careful not to damage the aluminum
wheels.
Use only the Lexus wheel nuts and wrench designed for your
aluminum wheels.
When balancing your wheels, use only Lexus balance weights or
equivalent and a plastic or rubber hammer.
As with any wheel, periodically check your aluminum wheels for
damage. If damaged, replace immediately.
SUSPENSION AND CHASSIS
CAUTION
Do not modify the suspension/chassis with lift kits, spacers,
springs, etc. It can cause dangerous handling characteristics,
resulting in loss of control.