2004 Lexus GX470 light

STARTING AND DRIVING
396
HILL-ST ART ASSIST CONTROL
SYSTEM
The hill-start assist control system 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 hill-start assist control
system. The vehicle may not be able to start
smoothly on road surfaces or off-road surfaces such
as extremely steep slopes or icy roads, on which
sliding can occur very easily.
Do not use the hill-start assist control system to stop
the vehicle. This system is not designed as a function
for stopping the vehicle on a uphill slope.
The hill-start assist control system will operate for 5
seconds maximally when all of the following conditions
apply.
When the transmission is in any of positions Dº, 4º,
3º, 2º or Lº
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 Pº or Nº
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 Rº.

Slip indicator light
When the hill-start assist control system 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.

STARTING AND DRIVING
397 The slip indicator light comes on for a few seconds when the
ignition key is turned to ONº. 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 system 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 system 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.
If the system is used frequently, the brake actuator
temperature may become too high and a buzzer will sound
intermittently.
In this case, a buzzer will sound intermittently. When the
temperature of the brake actuator goes down, the system will
begin to operate again. Until it restarts, the active traction
control system and downhill assist control system will not
operate; however, the conventional brake can be operated.
VSC TRACº warning light
If there is any abnormality in the system, the VSC TRACº
warning light will come on.
If the system malfunctions, the VSC TRACº warning light will
come on.
If the VSC TRACº warning light comes on, there may be an
abnormality in any of the following systems in addition to the
hill-start assist control system.
Downhill assist control system
Active traction control system
Vehicle stability control system
When the system is normal and the ignition key is turned to
ONº, 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 ONº
position.

STARTING AND DRIVING
398Depressing 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 system on such as 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 hill-start 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 VSC TRACº
warning light will come on and the hill-start assist control
system stops operating temporarily in order to protect the
brake actuator. (Although the hill-start 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
VSC TRACº warning light goes out.
If the warning 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 ONº.
The warning light remains on after the ignition key is turned
to ONº.
The warning light comes on while driving.
BRAKE SYSTEM
This brake system has 2 independent hydraulic circuits. If
either circuit should fail, the other 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 ONº 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
401 ABSº warning light
The light comes on when the ignition key is turned to the ONº
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 ABSº 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 ABSº 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 ONº 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 ABSº 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 anti-lock 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 ONº 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.

STARTING AND DRIVING
402
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 lightº on page 60.
Drum-in-disc 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.
BRAKE PAD WEAR LIMIT
INDICATORS
The brake pad wear limit indicators on your disc brakes
give a warning noise when the brake pads are worn to the
extent that replacement is required.
If you hear a squealing or scraping noise while driving, have the
brake pads checked and replaced by your Lexus dealer as
soon as possible. Expensive rotor damage can result if the
pads are not replaced when needed.

DRIVING TIPS
408
OPERATION IN FOREIGN
COUNTRIES
If you plan to drive your Lexus in another country...
First, comply with the vehicle registration laws.
Second, confirm the availability of the correct fuel (unleaded
and minimum octane rating).
TIPS FOR DRIVING IN VARIOUS
CONDITIONS
Always slow down in gusty crosswinds. This will allow you
much better control.
Drive slowly onto curbs and, if possible, at a right angle.
Avoid driving onto high, sharp-edged objects and other
road hazards. Failure to do so can lead to severe tire
damage such as a tire burst.
Drive slowly when passing over bumps or travelling on a
bumpy road. Otherwise, the impact could cause severe
damage to the tires and/or wheels.
When parking on a hill, turn the front wheels until they touch
the curb so that the vehicle will not roll. Apply the parking
brake, and place the transmission in Pº. If necessary, block
the wheels.
Washing your vehicle or driving through deep water may get
the brakes wet. To see whether they are wet, check that
there is no traffic near you and then press the pedal lightly.
If you do not feel a normal braking force, the brakes are
probably wet. To dry them, drive the vehicle cautiously while
lightly pressing the brake pedal with the parking brake
applied. If they still do not work safely, pull to the side of the
road and call a Lexus dealer for assistance.

DRIVING TIPS
409
CAUTION
Before driving off, make sure the parking brake is
fully released and that the parking brake reminder
light is off.
Do not leave your vehicle unattended while the
engine is running.
Do not rest your foot on the brake pedal while driving.
It can cause dangerous overheating, needless wear,
and poor fuel economy.
To drive down a long or steep hill, reduce your speed
and downshift. Remember, if you ride the brakes
excessively, they may overheat and not work
properly. See page 368.
Be careful when accelerating, upshifting,
downshifting or braking on a slippery surface. The
abrupt change in engine speed, such as sudden
acceleration or engine braking, could cause the
vehicle to spin or skid.
Do not drive in excess of the speed limit. Even if the
legal speed limit permits it, do not drive over 140 km/h
(85 mph) unless your vehicle has high-speed
capability tires. Driving over 140 km/h (85 mph) may
result in tire failure, loss of control and possible
injury. Be sure to consult a tire dealer to determine
whether the tires on your vehicle are high-speed
capability tires or not before driving at such speeds.

DRIVING TIPS
421
Hitches
If you wish to install a trailer hitch, you should consult with
your Lexus dealer.
Use only a hitch recommended by the hitch manufacture
and the one which conforms to the total trailer weight
requirement.
According to the hitch receiver type, the maximum gross
trailer weight and hitch that can be used differs. Refer to the
illustrations to confirm the hitch receiver type for your
vehicle.
If you wish to install an aftermarket hitch, the hitch must be
bolted securely to the vehicle frame and installed according
to the hitch manufactures' instructions.
The hitch ball and king pin should have a light coat of grease.
Lexus recommends the ball mount assembly be removed
when not towing to prevent injury and to prevent damage in
the event of a rear end collision. After removing the ball
mount assembly, install the grommet to the hitch to prevent
entry of dirt and mud.