2003 Lexus GX470 ignition

STARTING AND DRIVING
328
“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.
If 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 system
 Active traction control system
 Vehicle skid 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.
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 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 “VSC TRAC”
warning 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
“VSC TRAC” 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 “ON”.
 The warning light remains on after the ignition key is turned
to “ON”.
 The warning light comes on while driving.

STARTING AND DRIVING
330The 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 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 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 system.
 Downhill assist control system
 Active traction control system
 Vehicle skid 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
331
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 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 TRAC”
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 TRAC” 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 “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
be longer. 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
334“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 anti
−lock brake system, the brake
assist system, the active traction control system and the
vehicle skid 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 parts 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 the 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.

DRIVING TIPS
345
WINTER DRIVING TIPS
Make sure you have a proper freeze protection of engine
coolant.
Your coolant must contain ethylene−glycol type coolant for a
proper corrosion protection of aluminum components. Use
“Toyota Genuine Long Life Coolant” or equivalent. See
“Checking the engine coolant level” on page 422 for
instructions.
NOTICE
Do not use alcohol type antifreeze or plain water alone.
When it is extremely cold, we recommend to use 60% solution
for your Lexus, to provide protection down to about −50C
(−58 F). Do not use more than 70% solution for better coolant
performance.
Check the condition of the battery and cables.
Cold temperatures reduce the capacity of any battery, so it
must be in top shape to provide enough power for winter
starting. Page 447 tells you how to visually inspect the battery.
Your Lexus dealer and most service stations will be pleased to
check the battery charge level.
Make sure the engine oil viscosity is suitable for the cold
weather.
See page 420 for recommended viscosity. Leaving a heavy
summer oil in your vehicle during winter months may cause
harder starting. If you are not sure about which oil to use, call
your Lexus dealer − they will be pleased to help. Check the electronic ignition system for loose
connections or obvious damage.
Keep the door locks from freezing.
Squirt
lock de− icer or glycerine into the locks to keep them from
freezing.
Use a washer fluid containing an antifreeze solution.
This product is available at your Lexus dealer and most auto
parts stores. Follow the manufacturer’s directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute
because it may damage your vehicle’s paint.
Do not use your parking brake when there is a possibility
it could freeze.
When parking, put the transmission into “P” and block the front
wheels. Do not use the parking brake, or snow or water
accumulated in and around the parking brake mechanism may
freeze the parking brake, making it hard to release.
Keep ice and snow from accumulating under the fenders.
Ice and snow built up under your fenders can make steering
difficult. During bad winter driving, stop and check under the
fenders occasionally.

DRIVING TIPS
353
Maintenance
If you tow a trailer, your vehicle will require more frequent
maintenance due to the additional load. For this
information, please refer to the scheduled maintenance
information in the “Owner’s Manual Supplement /
Scheduled Maintenance”.
 Retighten all fixing bolts of the towing ball and bracket after
approximately 1000 km (600 miles) of trailer driving.
Connecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the “LO” (low)
mode. Turn the ignition switch off or push the “HEIGHT
CONTROL OFF” switch to turn off the rear height control air
suspension.
2. Connect a trailer.
3. Turn the ignition switch on or push the “HEIGHT CONTROL
OFF” switch to turn on the rear height control air suspension.
Select the “N” (normal) mode with the height select switch.
Disconnecting a trailer
Stop your vehicle and a trailer in line and perform the following:
1. Put the rear height control air suspension in the “LO” (low)
mode. (Make sure the vehicle height is in the “LO” (low) mode
by pushing the height select switch on the “
” side.)
2. Turn the ignition switch off or push the “HEIGHT CONTROL
OFF” switch to turn off the rear height control air suspension.
3. Set the supporting leg of a trailer on the ground and raise
the hitch by 100 mm (4 in.).
4. Turn the ignition switch on or push the “HEIGHT CONTROL
OFF” switch to turn on the rear height control air suspension.
5. Wait for about 20 seconds until the rear vehicle height is
lowered by the automatic leveling function.
6. Make sure the hitch is disconnected. If not, raise the hitch
higher and repeat steps 2 through 5.
7. Move the vehicle forward in the “LO” (low) mode where the
hitch does not touch anything in the “N” (normal) mode.
8. Put the rear height control air suspension in the “N” (normal)
mode.

IN CASE OF AN EMERGENCY
359
IF YOUR ENGINE STALLS WHILEDRIVING
If your engine stalls while driving ...
1. Reduce your speed gradually, keeping a straight line. Move
cautiously off the road to a safe place.
2. Turn on your emergency flashers.
3. Turn the ignition key to “ACC” or “LOCK”, and try starting
the engine again.
If the engine will not start, see “If your vehicle will not start”\
.
CAUTION
If the engine is not running, the power assist for the
brakes and steering will not work, so steering and
braking will be much harder than usual.
IF YOUR VEHICLE WILL NOT START
(a) Simple checks
Before making these checks, make sure you have followed the
correct starting procedure instructions in “How to start the
engine” on page 302 and that you have sufficient fuel. Since
your vehicle is equipped with the engine immobiliser system,
also check whether the other keys will start the engine. If they
work, your key may be broken. Have the key checked at your
Lexus dealer. If none of your keys work, the system is possibly
broken. Call your Lexus dealer. See “Keys” on page 8.
If the engine is not turning over or is turning over too
slowly
1. Check that the battery terminals are tight and clean.
2. If the battery terminals are O.K., switch on the interior light.
3. If the light is out, dim or goes out when the starter is cranked,
the battery is discharged. You may try jump starting. See “(c)
Jump starting” for further instruction.
If the light is O.K., but the engine still will not start, it needs
adjustment or repair. Call a Lexus dealer, Roadside
Assistance or Customer Service Assistance. (See
“Foreword”.)

IN CASE OF AN EMERGENCY
360
NOTICE
Do not pull or pushstart the vehicle. It may damage
the vehicle or cause a collision when the engine starts.
Also the threeway catalytic converter may overheat
and become a fire hazard.
If the engine turns over at its normal speed but will not
start
1. Turn the ignition key to “ACC” or “LOCK” and try starting the
engine again.
2. The engine may be flooded because of repeated cranking.
See “(b) Starting a flooded engine” for further instructions.
3. If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer Service
Assistance. (See “Foreword”.)
(b) Starting a flooded engine
If the engine will not start, your engine may be flooded
because of repeated cranking.
If this happens, turn the ignition key to “START” with the
accelerator pedal held down, and hold the key at this position
for about 30 seconds. Then the cranking hold function stops
cranking automatically, and you can try starting the engine with
your foot off the accelerator pedal.
If the engine does not start, wait a few minutes and try again.
If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer Service
Assistance. (See “Foreword”.)
(c) Jump starting
To avoid serious personal injury and damage to your
vehicle which might result from battery explosion, acid
burns, electrical burns, or damaged electronic
components, these instructions must be followed
precisely.
If you are unsure about how to follow this procedure, we
strongly recommend that you seek help from your Lexus
dealer, Roadside Assistance or Customer Service Assistance.
(See “Foreword”.)