2006 Lexus GS430 check engine light

STARTING AND DRIVING
425
G31038
Slip indicator light
Leave the system on during the ordinary driving so that it
can operate when needed.
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the traction control system is in the self −check mode, but does
not indicate a malfunction.
When the traction control system is operating, the following
conditions occur:
 The system controls the spinning of the drive wheels. At this
time, the slip indicator light blinks.
 You may feel vibration or noise in your vehicle, caused by
operation of the brakes. This indicates the system is
functioning properly.
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.
Traction control off mode
(twowheel drive models only)
G31008
If your wheels get stuck in a ditch when you are driving on
a severe off road and sand, turn off the traction control
system. This system that controls engine performance
interferes with the process of freeing your wheels.
To turn off: Push “TRAC OFF” switch.
The slip indicator light will come on.
The vehicle stability control system is always activated even if
the traction control system is turned off.

STARTING AND DRIVING
426GS430
only—When the vehicle speed exceeds about 50 km/h
(30 mph) even if the traction control system is turned off, the
system turns on automatically.
To turn on: Push “TRAC OFF” switch once again.
The slip indicator light will go off.
In the following cases, contact your Lexus dealer:
 The slip indicator light does not come on when the engine
switch is selected in “IG −ON” mode.
 The slip indicator 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 slip indicator light comes on in the normal driving mode
while driving.
Traction control system failure warning
G31039
 1
GS430 2GS300
If the traction control system malfunctions, the slip
indicator light (twowheel drive models only) and brake
system warning light (yellow) come on. At this time, the
above message appears. (GS430 only—In some cases,
the multiinformation display shows either “CHECK VSC”
or “CHECK ECB*” only.)
*: Electronically Controlled Brake System
If the message appears, the traction control system, vehicle
stability control system and hill− start assist control system do
not work. Although it is no problem to continue driving, have
your vehicle checked by your Lexus dealer as soon as
possible.

STARTING AND DRIVING
427
VEHICLE STABILITY CONTROLSYSTEM
The vehicle stability control system helps provide
comprehensive control of the systems such as antilock
brake system, traction control, engine control, etc. This
system automatically controls the brakes and engine to
help prevent the vehicle from skidding when cornering on
a slippery road surface or operating steering wheel
abruptly.
The vehicle stability control system is activated when the
vehicle speed is about more than 15 km/h (9 mph).
You may hear a sound in the engine compartment for a few
seconds just after the vehicle begins to move. This means that
the system is in the self− check mode, but does not indicate a
malfunction.
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.

STARTING AND DRIVING
428
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.
Vehicle stability control failure warning
G31039
 1
GS430 2GS300
If the vehicle stability control system malfunctions, the
slip indicator light (twowheel drive models only) and
brake system warning light (yellow) come on. At this time,
the above message appears. (GS430 only—In some
cases, the multiinformation display shows either
“CHECK VSC” or “CHECK ECB*” only.)
*: Electronically Controlled Brake System
If the message appears, the vehicle stability control system,
traction control system and hill −start assist control system do
not work. Although it is no problem to continue driving, have
your vehicle checked by your Lexus dealer as soon as
possible.

STARTING AND DRIVING
430GS430—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.
Keep the following in mind when driving:
 The hill −start assist control system operates for 5 seconds
maximally. If both the brake and accelerator pedals remain
undepressed for longer than 5 seconds, the system will
gradually stop operating.
 The hill− start assist control system is not designed for
stopping the vehicle on an uphill slope. When stopping the
vehicle, be sure to depress the brake pedal.
Hillstart assist control system failure
warning
G31039
 1 GS430 2GS300
If the hillstart assist control system malfunctions, the
slip indicator light (twowheel drive models only) and
brake system warning light (yellow) come on. At this time,
the above message appears. (GS430 only—In some
cases, the multiinformation display shows either
“CHECK VSC” or “CHECK ECB*” only.)
*: Electronically Controlled Brake System
If the message appears, the hill−start assist control system,
vehicle stability control system and traction control system do
not work. Although it is no problem to continue driving, have
your vehicle checked by your Lexus dealer as soon as
possible.

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432
Variable gear ratio steering system failure
warning
G31044
If there is any malfunction in the system, the above message
appears and the master warning light comes on.
If the warning message and light come on while driving, the
system is not working. Although conventional steering
operates when maneuvered, a larger degree of wheel
maneuvering (than at the time when the system is functioning
properly) is needed when driving at low speed. At this time, the
center position of the steering wheel could be changed.
Although it is no problem to continue driving, have your vehicle
repaired at your Lexus dealer.
VEHICLE DYNAMICS
INTEGRATED MANAGEMENT (GS430 only)
Vehicle Dynamics Integrated Management (VDIM) helps
manage control for vehicle stability control system,
antilock brake system, brake assist system, traction
control system, engine output control, hillstart 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.

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440
TIRE PRESSURE WARNINGSYSTEM
The tire pressure warning system warns you that the tire
inflation pressure is low.
The tire pressure warning syst em is not a substitute for
checking n ormal tire inflation pressure. Check the tire inflation
pressure with a tire pressure gauge regularly.
CAUTION
The warning system may not activate immediately if
bursts or sudden air leakage should occur.
G31003
 Tire pressure warning light
The tire pressure warning light comes on when the engine
switch “IG−ON” mode is selected, and goes off after a few
seconds. This means the tire pressure warning light is
operating properly. If the tire inflation pressure becomes low,
the light comes on again. At this time, the master warning light
comes on and the message “LOW TIRE” appears on the
multi−information display.
In this case, adjusting the tire inflation pressure will turn off the
light after a few minutes. If the light blinks, the tire pressure
warning system is not working properly. At this time, the
master warning light comes on and the message “CHECK
SYSTEM” appears on the multi −information display.

STARTING AND DRIVING
444If the tire pressure warning light blinks...
G31048
If the tire pressure warning light blinks when the engine
switch “IGON” mode is selected, the tire pressure
warning system is not working properly.
The system will be disabled in the following conditions:
(When the condition becomes normal, the system will work
properly.)

If tires not equipped with tire pressure warning valves and
transmitters are used.
 If the ID code on the tire pressure warning valves and
transmitters is not registered.
 If electronic devices or facilities using similar radio wave
frequencies are nearby.
 If a radio set at similar frequencies is in use in the vehicle. 
If a window tint that affects the radio wave signals is
installed.
 If the tire pressure warning select switch is set to a dif ferent
tire setting.
 If there is a lot of snow or ice on the vehicle, in particular
around the wheels or wheel housings.
 If non− genuine Lexus wheels are used.
 If tire chains are used.
 If the tire inflation pressure is more than 500 kPa (5.1
kgf/cm
2 or bar, 73 psi).
If the tire pressure warning light blinks frequently when the
engine switch “IG −ON” mode is selected, have it checked by
your Lexus dealer.
Even if you use genuine wheels, the tire pressure warning
system may not work properly with some types of tires.
Pushing the tire pressure warning reset switch should not turn
off the tire pressure warning light.