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STARTING AND DRIVING
421
CAUTION
Do not rely excessively on the vehicle stability
control system. Even if the vehicle stability control
system is operating, you must always drive carefully
and attentively to avoid serious injury. Reckless
driving will result in an accident. If the slip indicator
light blinks, sounding an alarm, special care should
be taken while driving.
Only use tires of specified size. The size,
manufacturer, brand and tread pattern for all 4 tires
should be the same. If you use the tires other than
specified, or different type or size, the vehicle
stability control system may not function correctly.
When replacing the tires or wheels, contact your
Lexus dealer.
In situations where the road surface is covered with
ice or snow, your vehicle should be fitted with snow
tires or tire chains.
G31038
Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light blinks and an alarm sounds intermittently. Special care
should be taken while driving.
GS430—The slip indicator light comes on when the engine
switch is selected in “IG−ON” mode. The light goes off when
the engine is started.
GS300—The slip indicator light comes on for a few seconds
when the engine switch is selected in “IG−ON” mode.
If the indicator light does not come on when the engine switch
is selected in “IG−ON” mode, contact your Lexus dealer.
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STARTING AND DRIVING
426
VEHICLE DYNAMICS
INTEGRATED MANAGEMENT
(GS430 only)
Vehicle Dynamics Integrated Management (VDIM) helps
manage control for vehicle stability control system,
anti−lock brake system, brake assist system, traction
control system, engine output control, hill−start assist
control system and also manages variable gear ratio
steering system and electric power steering system.
In order to control sudden steering wheel operation and
the sideslip on slippery road surfaces, this system
provides excellent vehicle stability by automatically
controlling the brake, engine output and front wheel
angle.
The state of the tires will affect the performance of the vehicle
dynamics integrated management system. Be sure to check
the following:
Are tires of specified size installed?
Are tires of identical type installed?
Do the tires have stipulated tire pressure?
Are the tires worn?
A problem with the tires or modified suspension systems will
have an adverse effect on the system and may cause a
malfunction, so be careful.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.
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.
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STARTING AND DRIVING
434If the low tire pressure warning light does not go off or comes
on during driving, it indicates that tire inflation pressure is low.
Make sure there is no flat tire. If the light comes on again even
after tire inflation pressure adjustment, you may have a flat tire.
If there is not adequate air pressure in the tires, the light will not
go off.
The light may turn on due to natural causes such as natural air
leaks or tire inflation pressure changes caused by
temperature. In this case, adjusting the tire inflation pressure
will turn off the light.
The tire pressure warning system is not a substitute for
checking tire inflation pressure.
For details about adjusting the tire inflation pressure, see
“Checking tire inflation pressure” on page 539.
If the low tire pressure warning light comes on, the action you
must take is different depending on the type of tires used.Vehicles with run−flat tires:
Stop your vehicle at a safe place as soon as possible and
check that the tire inflation pressure is as specified on the tire
and loading information label. If the low tire pressure warning
light comes on even after tire inflation pressure adjustment, it
is probable that you have a flat tire. If you cannot verify the tire
inflation pressure soon, go to the nearest Lexus dealer or
authorized tire dealer at the moderate speed and do not ever
exceed 90 km/h (55 mph) and have all your vehicle’s tires
checked and adjusted. And whether there is a flat tire or not
should be also checked at this time. If any tire must be
replaced, see “If you have a flat tire” on page 468.
If your vehicle is equipped with spare tire, the spare is not
equipped with the tire pressure sensor. So, the low tire
pressure warning light remains on even if the spare tire is
mounted.
The light goes off a few minutes after air is put into the deflated
tire.