light Lexus GX470 2006 Basic Functions In Frequent Use / LEXUS 2006 GX470 OWNER'S MANUAL (OM60B99U)

STARTING AND DRIVING
378
Turning on the system
1. Shift the fourwheel drive control lever to the “L”
position.
The system will not operate if the four−wheel drive control lever
is in the “H” position.
2. In order to make full use of the engine brake, putting the
transmission in “L” or “2” is recommended.
The system will operate even if the transmission selector lever
is in “D”, “4”, “3” or “N”. However, when it is in “L” or “2” the
engine brake can also be utilized enabling the system to
operate more effectively.
3. Push the “DAC” switch to turn the system on. The
downhill assist control system indicator light on the
instrument panel will come on. If the downhill assist control system indicator light flashes, the
transmission selector lever may be in “N” or four
−wheel drive
control lever may be in the “H” position.
If the indicator light does not come on when the switch is
pushed, contact your Lexus dealer.
 Slip indicator light
With the vehicle traveling at a speed of 25 km/h (15 mph) or
less, release your foot from the accelerator or brake pedal to
activate the system. The vehicle will descend the hill at a low
speed. While the system is operating, the slip indicator light on
the instrument panel will flash and the stop lights and high
mounted stoplight will be lit.

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379
If you push the “DAC” switch to turn the system off while it is
in operation, the system will stop operating gradually. The
downhill assist control system indicator light will flash to alert
the driver. To continue driving at a low speed, push the “DAC”
switch to turn the system on.
The slip indicator light and downhill assist control system
indicator
light come on for a few seconds when the ignition key
is turned to “ON”. If any of the indicator lights does not come
on when the ignition is turned on, contact your Lexus dealer.
The brake actuator temperature increases during continuous
operation of the following systems.
 Active traction control system
 Vehicle stability control system
 Downhill assist control system
 Hill −start assist control
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 downhill assist control system
can no longer operate. In this case, stop your vehicle
immediately 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 this time, the slip indicator light
will come on and the downhill assist control system stops
operating temporarily in order to protect the brake actuator.
(Although the downhill assist control system does not operate,
it is no problem to continue your driving.) The system will be
automatically restored after a short time and the slip indicator
light goes out.
“VSC TRAC” warning light
If there is any abnormality in the system, the “VSC TRAC”
warning light will come on. When the “DAC” switch is
pushed, the downhill assist control system indicator light
also flash.

STARTING AND DRIVING
380If the “VSC TRAC” warning light comes on, there may be an
abnormality in any of the following systems in addition to the
downhill assist control system.

Hill −start assist control
 Active traction control system
 Vehicle stability 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 it goes out after a few seconds.
If the “VSC TRAC” warning light and slip indicator light comes
on while driving, the system does not work. However, as
normal braking operates when being applied, it 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.
HILLSTART ASSIST CONTROL
The hillstart assist control assists you in starting to move
up a steep or slippery hill. When you start to move up the
hill slope, the system helps to prevent the vehicle from
rolling backward in the interval while you move your foot
from the brake pedal to the accelerator pedal.
CAUTION
 Do not rely excessively on the hillstart assist
control. The vehicle may not be able to start
smoothly on road surfaces or offroad surfaces such
as extremely steep slopes or icy roads, on which
sliding can occur very easily.
 Do not use the hillstart assist control to stop the
vehicle. The hillstart assist control is not designed
as a function for stopping the vehicle on a uphill
slope.

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381
The hillstart assist control will operate for 5 seconds
maximally when all of the following conditions apply.

When the transmission is in any of positions “D”, “4”,
“3”, “2” or “L”
 When the brake pedal is not depressed
The system is designed to operate when the vehicle is starting
on an uphill slope; therefore, if the transmission is in “P” or “\
N”
it will not operate. It will not operate either if the vehicle starts
to move in reverse on a slope with the transmission in the “R”.
 Slip indicator light
When the hill−start assist control is operating, the slip indicator
light flashes and an alarm sounds intermittently. At the same
time, the stop lamps and high mounted stoplight are lit.
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. Keep in mind the following when driving.

The hill −start assist control operates for 5 seconds
maximally. If both the brake and accelerator pedals remain
undepressed for longer than 5 seconds, the buzzer will
sound at more frequent intervals and the system will
gradually stop operating.
 The hill −start assist control is not designed as a function for
stopping the vehicle on a uphill slope. When stopping the
vehicle, be sure to depress the brake pedal.
The brake actuator temperature increases during continuous
operation of the following systems.
 Active traction control system
 Vehicle stability control system
 Downhill assist control system
 Hill −start assist control
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 hill −start assist control can no
longer operate. In this case, stop your vehicle immediately at
a safe place.

STARTING AND DRIVING
382If the system continues to operate, the buzzer sound changes
from intermittent to continuous. (The continuous buzzer
sounds
for about 3 seconds.) At this time, the slip indicator light
will come on and the hill −start assist control stops operating
temporarily in order to protect the brake actuator. (Although
the hill−start assist control does not operate, it is no problem
to continue your driving.) The system will be automatically
restored after a short time and the slip indicator light goes out.
“VSC TRAC” warning light
If there is any abnormality in the system, the “VSC TRAC”
warning light will come on.
If the system malfunctions, the “VSC TRAC” warning light will
come on.
If the “VSC TRAC” warning light comes on, there may be an
abnormality in any of the following systems in addition to the
hill−start assist control.
 Downhill assist control system
 Active traction control system
 Vehicle stability 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
383
Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
If the “VSC TRAC” warning light and slip indicator light comes
on while driving, the system does not work. However, as
normal braking operates when being applied, it 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.
BRAKE SYSTEM
This brake system has 2 independent hydraulic circuits. If
either circuit should fail, the o ther will still work. However, the
pedal will be harder to press, and your stopping distance will
increase. Also, the brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake booster
The brake booster uses brake fluid pressurized by the pump
to power−assist the brakes. If the brake booster fails during
driving, the brake system warning light comes on and buzzer
sounds continuously. In this case, the brakes may not work
properly. If they do not work well, depress the brake pedal
firmly. If the brake system warning light comes on, immediately
stop your vehicle and contact your Lexus dealer.
The brake system warning light may stay on for about 60
seconds after the ignition key is turned to the “ON” position. It
is normal if the light turns off after a while.
Depressing the brake pedal repeatedly may turn on the brake
system warning light and buzzer. It is normal if the light goes
out and the buzzer stops sounding after a few seconds.

STARTING AND DRIVING
386“ABS” warning light
1U.S.A.2Canada
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 anti −lock brake system, the brake
assist system, the active traction control system and the
vehicle stability control system do/does not operate, but the
brake system still operates conventionally.
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 could 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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387
Brake assist system
When you slam the brakes on, the brake assist system
judges as an emergency stop and provides more powerful
braking for a driver who cannot hold down the brake pedal
firmly.
When you slam the brakes on, more powerful braking will be
applied. At this time, you may hear a sound in the engine
compartment and feel the vibrations of the brake pedal. This
does not indicate a malfunction.
The brake assist system becomes operative after the vehicle
has accelerated to a speed in excess of approximately 10 km/h
(6 mph). It stops operating when the vehicle decelerates to a
speed below approximately 5 km/h (3 mph).
The brake assist system may not work for about 60 seconds
after the engine is started.
For an explanation of this system’s warning light, see “ABS
warning light” on page 57.
Drumindisc type parking brake system
Your vehicle has a drum−in−disc type parking brake system.
This type of brake system needs bedding −down of the brake
shoes periodically or whenever the parking brake shoes and/or
drums are replaced.
Have your Lexus dealer perform the bedding −down.
TIRE PRESSURE WARNING
SYSTEM
The tire pressure warning system is designed to provide
warning when tire inflation pressure of one or more of
your tires (including the spare tire) is low. The low tire
pressure warning light comes on to inform you that low
tire inflation pressure may hamper driving.
Low tire pressure warning light
This light comes on when the ignition key is turned to the “ON”
position. It goes off after a few seconds. This indicates that the
tire pressure warning system is functioning properly.

STARTING AND DRIVING
388If the low tire pressure warning light comes on or blinks,
do the following.
If the warning light comes on:
Stop your
vehicle in a safe place as soon as possible and
check that the inflation pressure of all tires (including the
spare tire) is as specified on the tire and loading
information label. (See “Checking tire inflation pressure”
on page 523.) If the warning light comes on even after tire
inflation pressure adjustment, you may have a flat tire. If
you have a flat tire, replace it with the spare tire. For
details, see “If you have a flat tire” on page 432.
The warning light goes off a few minutes after air is put into the
deflated tire.
This warning light may turn on due to natural causes such as
natural air leaks or tire pressure changes caused by
temperature. In this case, adjusting the tire pressure will turn
off the warning light.
CAUTION
When the low tire pressure warning light comes on,
observe the following instructions:
 Depending on the conditions, reduce to an
appropriate speed as soon as possible.
 Adjust the tire pressure to the specified level as soon
as possible.
 Avoid abrupt steering wheel maneuvering and
braking. Tire deterioration may reduce steering
wheel control and brake effectiveness. This may lead
to serious injury or death.
 The tire pressure warning system may not activate
immediately if sudden bursts of air leakage occur.

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NOTICE
Do not use liquid sealants for a flat tire as air pressure
sensors will be damaged.
 When the tires must be repaired or replaced, have
them repaired or replaced by the nearest Lexus
dealer or authorized tire dealer. The tire pressure
sensors will be affected by the installation or removal
of tires.
 The tire pressure warning system is not to be used as
a substitute for regular inspections. Be sure to check
the air pressure in the tires on a regular basis.
 When the tires must be replaced, replace the
grommets for air pressure sensors as well.
If the warning light blinks:
The tire pressure warning system may be malfunctioning.
Contact your Lexus dealer.
System malfunction
The tire pressure warning system does not function
properly under certain circumstances. In the following
cases, the low tire pressure warning light may not come
on even if the tire inflation pressure is low, or it may come
on when the tire inflation pressure is actually normal.
Electric devices or facilities using similar radio wave
frequencies are nearby.
 A radio set to similar frequencies is in use.
 A lot of snow or ice covers the vehicle, in particular, around
the wheels or wheel housings.
 The tires are not equipped with an air pressure sensor.
 Tire chains are used.
 Non −genuine Lexus wheels are used.
 Although the tires are equipped with air pressure sensors,
the selector switch (see page 393.) is set to other tire setting.