warning Lexus GX470 2005 Scheduled Maintenance Guide / LEXUS 2005 GX470 (OM60B11U) Service Manual

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(f) Parking and stopping tips
If you immediately stop the engine to park the vehicle after
off±road driving, the vehicle height is lowered slightly as the
vehicle becomes cool. When parking, make sure there is
nothing that will be in contact with the underbody of the vehicle.
When you start the engine, the vehicle returns to the previous
height.
If you park the vehicle for a long time, the vehicle height may
be gradually lowered. When parking for a long time, make sure
there is nothing that will be in contact with the underbody of the
vehicle. When you start the engine, the vehicle returns to the
previous height.
If you stop the engine, the vehicle height may change in
accordance with the change in the temperature. When you
start the engine, the vehicle returns to the previous height.
(g) Rear height control failure warning
If there is a problem somewhere in the rear height control air
suspension, the ªNº mode is automatically selected. If this
occurs, the height control ªOFFº indicator light blinks and the
vehicle height control cannot be activated until the malfunction
is corrected. If this is the case, bring your vehicle to your Lexus
dealer as soon as possible and have it checked.
ELECTRONIC MODULATED SUSPENSION
This electronic modulated suspension adjusts the
damping effect on the shock absorbers with the control
switch. Select one of the 4 modes which is suited to the
driving conditions with the control switch to provide good
riding comfort and stability.
1For driving on a bumpy road
2For ordinary driving such as in the city traffic
3For moderate high speed driving
4For sporty type driving such as on winding mountain
roads and high speed driving
5Soft
6Firm

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ªVSC TRACº warning light
This light warns that there is a problem somewhere in the
following.
Active traction control system
 Vehicle stability control system
 Downhill assist control system
 Hill±start assist control
When the system is normal and the ignition key is turned to
ªONº, 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 ªONº
position. Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
If the ªVSC TRACº warning light and slip indicator 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 ªONº.
 The warning light remains on after the ignition key is turned
to ªONº.
 The warning light comes on while driving.

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The indicator light comes on when the system is on while
driving.
NOTICE
Make sure that the center differential lock indicator light
goes off before normal driving.
ªVSC TRACº warning light
This light warns that when there is a problem somewhere in the
following. 
Vehicle stability control system
 Active traction control system
 Downhill assist control system
 Hill±start assist control
When the system is normal and the ignition key is turned to
ªONº, 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 ªONº
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 stability 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 ªONº.
 The warning light remains on after the ignition key is turned
to ªONº.

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The warning light comes on while driving.
DOWNHILL ASSIST CONTROL
SYSTEM
The downhill assist control system is a system that
assists the deceleration of the engine brake when you
drive down a steep hill. When you are driving down a hill
with the four±wheel drive control lever in the ªLº position,
push the ªDACº switch to limit the vehicle's acceleration.
If the vehicle is traveling at a speed of 25 km/h (15 mph) or
less, you can descend at a constant speed.
CAUTION
Do not rely excessively on the downhill assist control
system. It may not be able to maintain a low speed over
road surf aces or off±road surfaces on which sliding can
easily occur, such as extremely steep slopes or icy or
muddy roads.
Turning on the system
1. Shift the four±wheel drive control lever to the ªLº
position.
The system will not operate if the four±wheel drive control lever
is in the ªHº position.
2. In order to make full use of the engine brake, putting the
transmission in ªLº or ª2º is recommended.
The system will operate even if the transmission selector lever
is in ªDº, ª4º, ª3º or ªNº. However, when it is in ªLº or ª2º the
engine brake can also be utilized enabling the system to
operate more effectively.
3. Push the ªDACº switch to turn the system on. The
downhill assist control system indicator light on the
instrument panel will come on.

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ªVSC TRACº warning light
If there is any abnormality in the system, the ªVSC TRACº
warning light will come on. When the ªDACº switch is
pushed, the downhill assist control system indicator light
also flash.If the ªVSC TRACº 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
ªONº, 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 ªONº
position.
Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
If the ªVSC TRACº 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 ªONº.
 The warning light remains on after the ignition key is turned
to ªONº.
 The warning light comes on while driving.

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ªVSC TRACº warning light
If there is any abnormality in the system, the ªVSC TRACº
warning light will come on.
If the system malfunctions, the ªVSC TRACº warning light will
come on.
If the ªVSC TRACº 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
ªONº, 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 ªONº
position. Depressing the brake pedal repeatedly may turn on the light.
It is normal if it goes out after a few seconds.
If the ªVSC TRACº 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 ªONº.
 The warning light remains on after the ignition key is turned
to ªONº.
 The warning light comes on while driving.

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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 ªONº 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. You may hear a small sound in the engine compartment after
the engine is started or the brake pedal is depressed
repeatedly. This is a pump pulsating sound of the brake
system, and it is not a malfunction.
CAUTION

Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your brake fluid
pressure reserve.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will increase.
Anti±lock brake system
The anti±lock brake system is designed to automatically
help pr event lock±up of the wheels during a sudden brake
or braking on slippery road surfaces. This assists in
providing directional stability and steering performance
of the vehicle under these circumstances.
Effective way to press the ABS brake pedal: When the
anti±lock brake system function is in action, you may feel the
brake pedal pulsating and hear a noise. In this situation, to
let the anti±lock brake system work for you, just hold the
brake pedal down more firmly. Do not pump the brake in a
panic stop. This will result in reduced braking performance.

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Driving over the steps such as the joints on the road.
 Driving on roads where the road surface is pitted or
has other differences in surface height.
Install all 4 tires of specified size at appropriate
pressure: The anti±lock brake system detects vehicle
speeds using the speed sensors for respective wheels'
turning speeds. The use of tires other than specified
may fail to detect the accurate turning speed resulting
in a longer stopping distance.ªABSº warning light

1U.S.A.2Canada
The light comes on when the ignition key is turned to the ªONº
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 ªABSº 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 ªABSº 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.

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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 ªONº 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 ªABSº 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 ªONº 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.
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 ªABS
warning lightº on page 67.
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.

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TIRE PRESSURE WARNINGSYSTEM
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 ªONº
position. It goes off after a few seconds. This indicates that the
tire pressure warning system is functioning properly. If 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 ªChecking tire inflation pressureº
on page 574.) 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 ªIf you have a flat tireº on page 497.
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.