traction control Lexus GX470 2003 Electrical Components / LEXUS 2003 GX470 OWNER'S MANUAL (OM60A45U)

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
48
(f) “ABS” Warning Light
The light comes on when the ignition key is turned to the “ON”
position. If the anti−lock brake system and the brake assist
system work properly, the light turns off after a few seconds.
Thereafter, if either of the systems malfunctions, the light
comes on again.
When the “ABS” warning light is on (and the brake system
warning light is off), the following systems do not operate, but
the brake system still operates conventionally.
 Anti− lock brake system
 Brake assist system
 Active traction control system
 Vehicle skid control system
 Downhill assist control system
 Hill− start assist control system
When the “ABS” warning light is on (and the brake system
warning light is off), the anti −lock brake system does not
operate, so that the wheels will lock up during a sudden braking
or braking on slippery road surfaces.
If either of the following conditions occurs, this indicates
a malfunction somewhere in the components monitored
by the warning light system. Contact your Lexus dealer as
soon as possible to service the vehicle.
 The light does not come on when the ignition key is turned
to the “ON” position, or remains on.
 The light comes on while you are driving. A warning light turning on briefly during operation does not
indicate a problem.
CAUTION
If the “ABS” warning light remains on together with the
brake system warning light, immediately stop your
vehicle at a safe place and contact your Lexus dealer.
In this case, not only the antilock brake system will fail
but also the vehicle will become extremely unstable
during braking.
Either of the following conditions may occur, but do not
indicate a malfunction:

The light may stay on for about 60 seconds after the ignition
key is turned to the “ON” position. It is normal if it turns off
after a while.
 Depressing the brake pedal repeatedly may turn on the
light. It is normal if it turns off after a few seconds.

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
50
(j) “VSC TRAC” Warning Light
The light warns that there is a problem somewhere in the
following.
Vehicle skid control system
 Active traction control system
 Downhill assist control system
 Hill− start assist control system
The light will come on when the ignition key turned to “ON”, and
will go off after a few seconds.
It is not a malfunction that the warning light may stay on for 60
seconds after the ignition key is turned to the “ON” position.
Depressing the brake pedal repeatedly may turn on the lights.
It is normal if they go out after a few seconds.
There is no problem when the “VSC TRAC” warning light
comes on when the brake actuator temperature becomes high.
If the light comes on while driving, the above mentioned
systems do not work. However, as conventional braking
operates when applied, there is no problem to continue your
driving.
In the following cases, contact your Lexus dealer:
 The warning light does not come on after the ignition key is
turned to “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.
(k) Discharge Warning Light
This light warns that the battery is being discharged.
If it comes on while you are driving, stop the vehicle, turn off the
engine, and check for the cause. Look first at the engine drive
belt.
 If it is loose or broken, the generator will not charge the
battery properly.
 If the belt is O.K., there is a problem somewhere in the
charging system.
The engine ignition will continue to operate, however, until the
battery is discharged. Turn off the air conditioning, blower,
radio, etc., and drive directly to the nearest Lexus dealer or
repair shop.
NOTICE
Do not continue driving if the engine drive belt is broken
or loose.
(l) Low Engine Oil Pressure Warning Light
This light warns that the engine oil pressure is too low.
If it flickers or stays on while you are driving, pull off the road
to a safe place and stop the engine immediately. Call a Lexus
dealer or qualified repair shop for assistance.

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GAUGES, METERS AND SERVICE REMINDER INDICATORS
52
How to check all the service reminder
indicators
(except the low fuel level warning light):
1. Apply the parking brake.
2. Open the door.
The following service reminder indicator should come on. It
goes off when you close the door completely.
3. Place the four−wheel drive control lever in “N” position and
the selector lever in “P” position and turn the ignition key to
“ACC”.
The following service reminder indicator should come on. It
goes off when you place the four −wheel drive control lever in
“H” or “L” position.
4. Turn the ignition key to “ON”.
The following service reminder indicators should come on.

w72a
w73
The following service reminder indicator goes off after a few
seconds.

The anti −lock brake system warning light, vehicle skid control
system off indicator light and vehicle skid control system and
active traction control system warning light may stay on for
about 60 seconds after the ignition key is turned to the “ON”
position. It is normal if they go out after a while.

SECTION 3 – 1
296
STARTING AND DRIVING
Starting and driving
Three−way catalytic converters297
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Engine exhaust caution 298
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Before starting the engine 299
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Ignition switch with steering lock 300
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Parking brake 301
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
How to start the engine 302
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Automatic transmission 303
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Four−wheel drive system 309
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Cruise control 312
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. . . . . .
Rear height control air suspension 315
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Electronic modulated suspension 320
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Active traction control system 321
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Vehicle skid control system 323
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Downhill assist control system 326
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Hill −start assist control system 329
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Brake system 331
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Brake pad wear limit indicators 335
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Limited −slip differential 336
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Types of tires 336
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STARTING AND DRIVING
310
NOTICE
As soon as the center differential lock switch is turned
on, the “VSC OFF” indicator light comes on. After the
wheels are out of the ditch or off the slippery or bumpy
surface, turn the center differential lock switch off.
Make sure the center differential lock indicator light and
vehicle skid control system off indicator light turn off.
“H” (high speed position, center differential unlocked):
Lever at “H”, center differential lock button left out
Use this for normal driving on all types of roads, from dry
hard−surfaced roads to wet, icy or snow −covered roads. This
position gives greater economy, quietest ride, least wear and
better vehicle control.
“H” (high speed position, center differential locked):
Lever at “H”, center differential lock button pushed in
Use this for greater traction when you experience a loss of
power, such as wheel slipping, in the center dif ferential unlock
mode.
“N” (neutral position): Lever at “N”
No power is delivered to the wheels. The vehicle must be
stopped. “L” (low speed position, center differential unlocked):
Lever at “L”, center differential lock button left out
Use this for maximum power and traction. Use this for climbing
or descending steep hills, off
−road driving, and hard pulling in
sand or mud.
In this mode, the braking feeling that occurs when the wheels
are negotiating a sharp corner is further reduced than in the “L”
(low position, center differential locked) mode.
“L” (low speed position, center differential locked): Lever
at “L”, center differential lock button pushed in
Use this for maximum power and traction. Use this for hard
pulling in situations the vehicle cannot negotiate even in the “L”
(low speed position, center differential unlocked) mode. Also,
using this mode when driving down steep off −road inclines will
help contribute to increased vehicle stability.
The indicator light tells when the differential lock is engaged.
Note that the differential is not still locked as long as the
indicator light remains off.
When the operation is not completed, the indicator blinks. If the
indicator light does not go off when you push out the center
differential lock switch, drive straight ahead while accelerating
or decelerating, or drive in reverse.
The center differential lock system operation is not completed
within 5 seconds while the cruise control system is set, cancel
the cruise control system. To cancel the cruise control system,
see “Cruise control” on page 312.
If the indicator light does not go off when you push out the
center differential lock button, drive straight ahead while
accelerating or decelerating, or drive in reverse.

STARTING AND DRIVING
311
See “(b) Shifting procedure” for further instructions.
Advice for driving on slippery roads in “L” (low speed
position) mode
If you shift the four−wheel drive control lever to “L”, the
automatic transmission lever to “2” when you drive in steep
off−road areas, the output of the brake can be controlled
effectively by the active traction control system, which assists
the driver to control the driving power of 4 wheels.
Use the “L” position of the automatic transmission lever for
maximum power and traction when your wheels get stuck or
when you drive down a steep incline. In the following cases,
the out put of the brake can be controlled by the active traction
control system if the engine speed is under 3,000 rpm
(normally engine speed is under 3,000 rpm when the wheels
get unstuck).
 The four− wheel drive control lever in the “L” position and the
automatic transmission lever in the “L” position or the
automatic transmission lever in the “D” or “2” with the
transmission downshifting to the first gear.
 The four− wheel drive control lever in the “L” position and the
automatic transmission lever in the “R” position
(As for the automatic transmission lever positions, see
“Automatic transmission” on page 303.)
(b) Shifting procedure
To shift between unlock and lock modes in “H”, push the
center differential lock button.
To shift between unlock and lock modes in “L”, push the
center differential lock button.
To shift between “H” and “L”, stop the vehicle, put the
transmission into “N” and move the four −wheel drive control
lever.
CAUTION
Never move the fourwheel drive control lever if wheels
are slipping. Stop the slipping or spinning before
shifting.
NOTICE
For normal driving on dry and hard surface roads,
unlock the center differential. To prevent damage to the
center differential lock system, do not push the center
differential lock button when the vehicle is cornering or
when its wheels are spinning freely of f the ground. If the
indicator light does not go off when unlocking the
center differential, drive straight ahead while
accelerating or decelerating, or drive in reverse.

STARTING AND DRIVING
321
When your vehicle is loaded heavily or you are driving in an
unpaved road, the mode

3
or 4
will be recommended. To
provide good vehicle stability, the damping effect will be harder
than for ordinary driving mode.
With the four−wheel drive control lever at “L”, the damping
effect suitable for off −road driving will be harder in any mode.ACTIVE TRACTION CONTROL
SYSTEM
The active traction control system automatically helps
prevent the spinning of 4 wheels when the vehicle is
started or accelerated on slippery road surfaces.
When the ignition key is turned to “ON”, the system
automatically turns on.
CAUTION
Under certain slippery road conditions, full traction of
the vehicle and power to the 4 wheels cannot be
maintained, even though the traction control system is
in operation. Do not drive the vehicle under any speed
or maneuvering conditions which may cause the
vehicle to lose traction control. In situations where the
road surface is covered with ice or snow, your vehicle
should be fitted with snow tires or tire chains. Always
drive at an appropriate and cautious speed for the
present road conditions.

STARTING AND DRIVING
322
 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 when the engine is started or just after the vehicle
begins to move. This means that the active traction control
system is in the self−check mode, but does not indicate a
malfunction.
When the active traction control system is operating, the
following conditions occur:
 The system controls the spinning of the 4 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. The slip indicator light comes on for a few seconds when the
ignition key is turned to “ON”. If the indicator light does not
come on when the ignition is turned on, contact your Lexus
dealer.
“VSC TRAC” warning light
This light warns that there is a problem somewhere in the
following.

Active traction control system
 Vehicle skid control system
 Downhill assist control system
 Hill− start assist control system
When the system is normal and the ignition key is turned to
“ON”, the warning light will come on and will go off after a few
seconds. It is not a malfunction that the warning light may stay
on for 60 seconds after the ignition key is turned to the “ON”
position.

STARTING AND DRIVING
323
Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
The brake actuator temperature increases during continuous
operation of
the above mentioned systems such as on slippery
roads. If the brake actuator temperature becomes too high
while any of the systems is operating, a buzzer will start to
sound intermittently to indicate that the active traction control
system can no longer operate. In this case, immediately stop
your vehicle at a safe place.
If the system continues to operate, the buzzer sound changes
from intermittent to continuous. (The continuous buzzer
sounds for about 3 seconds.) At the time, the “VSC TRAC”
warning light will come on and the active traction control
system temporarily stops operating in order to protect the
brake actuator. (Although the active traction control system
does not operate, there is no problem to continue your driving.)
The system will be automatically restored after a short time and
the “VSC TRAC” warning light goes out.
If the light comes on while driving, the active traction control
system does not work. However, as normal braking operates
when being applied, there is no problem to continue your
driving.
In the following cases, contact your Lexus dealer:
 The warning light does not come on after the ignition key is
turned to “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.
VEHICLE SKID CONTROL SYSTEM
The vehicle skid control system helps provide integrated
control of the systems such as antilock brake system,
traction control, engine control, etc. This system
automatically controls t he output of the brakes or engine
to help prevent the vehicle from skidding when cornering
on a slippery road surface or operating steering wheel
abruptly.
The vehicle skid control activates when the vehicle speed is
more than following speed:
Four− wheel drive control lever in “H” 15 km/h (9 mph) . . .
Four−wheel drive control lever in “L” 30 km/h (19 mph) . . .
You may hear a sound in the engine compartment for a few
seconds when the engine is started or 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 skid control
system. Even if the vehicle skid control system is
operating, you must always drive carefully and
attentively to avoid serious injury. Reckless driving
will result in an unexpected accident. If the slip
indicator light blinks and an alarm sounds, special
care should be taken while driving.

STARTING AND DRIVING
325

The indicator light remains on after the ignition is turned on.
 The indicator light comes on when the system is on while
driving.
NOTICE
Make sure that the center dif ferential lock indicator light
goes off before normal driving.
“VSC TRAC” warning light
This light warns that when there is a problem somewhere in the
following. 
Vehicle skid control system
 Active traction control system
 Downhill assist control system
 Hill− start assist control system
When the system is normal and the ignition key is turned to
“ON”, the warning light will come on and will go off after a few
seconds. It is not a malfunction that the warning light may stay
on for 60 seconds after the ignition key is turned to the “ON”
position.
Depressing the brake pedal repeatedly may turn on the light.
It is normal if they go out after a few seconds.
If the light comes on while driving, the vehicle skid control
system does not work. However, as normal braking operates
when being applied, there is no problem to continue your
driving.
In the following cases, contact your Lexus dealer:
 The warning light does not come on after the ignition key is
turned to “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.