check engine Lexus GX470 2003 How To Use This Manual / LEXUS 2003 GX470 (OM60979U) User Guide

STARTING AND DRIVING
320
(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 “N” mode is automatically selected. If this
occurs, the height control “OFF” 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.
1 For driving on a bumpy road
2 For ordinary driving such as in the city traffic
3 For moderate high speed driving
4 For sporty type driving such as on winding mountain
roads and high speed driving
5 Soft
6 Firm
We recommend you to select the mode
2
for ordinary
driving. The damping effect will be changed automatically to
provide good riding comfort.

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
332You 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 be longer.
Antilock brake system
The antilock brake system is designed to automatically
help prevent lockup 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.
The anti−lock brake 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).
Depressing the brake pedal on slippery road surfaces such as
on the manhole cover, the steel plate under the construction,
joints in the bridge, etc. on a rainy day tends to activate the
anti−lock brake system.
You may hear a click or motor 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
anti−lock brake system is in the self −check mode, and does not
indicate a malfunction.
When the antilock brake system is activated, the
following conditions may occur. They do not indicate a
malfunction of the system:
 You may hear the anti −lock brake system operating and feel
the brake pedal pulsating and the vibrations of the vehicle
body and steering wheel. You may also hear the motor
sound in the engine compartment even after the vehicle is
stopped.
 At the end of the anti−lock brake system activation, the
brake pedal may move a little to the forward.

STARTING AND DRIVING
335
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 48.
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.
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
344
When driving offroad or in rugged terrain, do not
drive at excessive speeds, jump, make sharp turns,
strike objects, etc. This may cause loss of control or
vehicle rollover causing death or serious injury. You
are also risking expensive damage to your vehicle’s
suspension and chassis.
NOTICE
 If driving through water, such as when crossing
shallow streams, first check the depth of the water
and the bottom of the river bed for firmness. Drive
slowly and avoid deep water.
 Take all necessary safety measures to ensure that
water damage to the engine or other components
does not occur.
Water entering the engine air intake will cause severe
engine damage.
Water can wash the grease from wheel bearings,
causing rusting and premature failure, and may also
enter the differentials, transmission and transfer
case, reducing the gear oil’s lubricating qualities.
 Sand and mud that has accumulated in brake drums
and around brake discs may affect braking ef ficiency
and may damage brake system components.
 Always perform a maintenance inspection after each
day of offroad driving that has taken you through
rough terrain, sand, mud, or water. For scheduled
maintenance information, refer to the “Owner’s
Manual Supplement / Scheduled Maintenance”.

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
352
Tires
Ensure that your vehicle’s tires are properly inflated. Adjust
the tire pressure to the recommended cold tire pressure
indicated below.
Tire pressure: 220 kPa (2.2 kgf/cm
2 or bar, 32 psi)
 The trailer tires should be inflated to the pressure
recommended by the trailer manufacturer in respect to the
total trailer weight.
Trailer lights
 Socket for trailer lights
Your vehicle is equipped with a wire harness stored in the rear
end underbody. Models with tow hitch receiver are fitted with
a socket for trailer lights under the rear bumper. Use either of
them to connect and operate the trailer lights. However, the
trailer lights must comply with federal, state/provincial and
local regulations. See your local recreational vehicle dealer or
rental agency for the correct type of wiring and relays for your
trailer. Check for correct operation of the turn signals and stop
lights each time you hitch up. Direct splicing may damage your
vehicle’s electrical system and cause a malfunction of your
lights.
Breakin schedule
Lexus recommends that you do not tow a trailer with a new
vehicle or a vehicle with any new power train component
(engine, transmission, differential, wheel bearing, etc.) for the
first 800 km (500 miles) of driving.

DRIVING TIPS
356When restarting out after parking on a slope:
1. With the transmission in “P” position, start the engine. Be
sure to keep the brake pedal depressed.
2. Shift into the “3”, “2”, “L” or “R” position.
3. Release the parking brake and brake pedal and slowly pull
or back away from the wheel blocks. Stop and apply your
brakes.
4. Have someone retrieve the blocks.
CAUTION

Do not exceed 72 km/h (45 mph) or the posted towing
speed limit, whichever is lower. Because instability
(swaying) of a towing vehicletrailer combination
usually increases as the speed increases, exceeding
72 km/h (45 mph) may cause loss of control.
 Slow down and downshift before descending steep
or long downhill grades. Do not make sudden
downshifts.
 Avoid holding the brake pedal down too long or too
frequently. This could cause the brakes to overheat
and result in reduced braking efficiency.
HOW TO SAVE FUEL AND MAKE
YOUR VEHICLE LAST LONGER
Improving fuel economy is easy − just take it easy. It will help
make your vehicle last longer, too. Here are some specific tips
on how to save money on both fuel and repairs:
 Keep your tires inflated at the correct pressure. Check
the pressure every two weeks, or at least once a month.
Underinflation causes tire wear and wastes fuel.
 Do not carry unneeded weight in your vehicle. Excess
weight puts a heavier load on the engine, causing greater
fuel consumption.
 Avoid lengthy warmup idling. Once the engine is
running smoothly, begin driving − but gently. Remember,
however, that on cold winter days this may take a little
longer.
 Always keep the automatic transmission selector lever
in the “D” position when engine braking is not required.
Driving with the overdrive off will reduce the fuel economy.
(For details, see “Automatic transmission” on page 303.)
 Accelerate slowly and smoothly. Avoid jackrabbit starts.
 Avoid long engine idling. If you have a long wait and you
are not in traffic, it is better to turn off the engine and start
again later.
 Avoid engine overrevving. Use a gear position suitable
for the road on which you are traveling.

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”.)