2003 Lexus GX470 maintenance ac system

INTRODUCTION
ii
New vehicle warranty
Your new vehicle is covered by the following Lexus limited
warranties:
New vehicle warranty
 Emission control systems warranty
 Others
For further information, please refer to the “Owner’s Guide”,
“Owner’s Manual Supplement” or “Warranty Booklet”.
Your responsibility for maintenance
It is the owner’s responsibility to make sure the specified
maintenance is performed. Section 5 of this Owner’s Manual
gives details of these maintenance requirements. Included in
Section 6 is general maintenance. For scheduled
maintenance information, please refer to the “Owner’s Manual
Supplement / Scheduled Maintenance”.
Accessories, spare parts and modification of
your Lexus
A wide variety of non −genuine spare parts and accessories for
Lexus vehicles are currently available in the market. You
should know that Toyota does not warrant these products and
is not responsible for their performance, repair, or
replacement, or for any damage they may cause to, or adverse
effect they may have on, your Lexus vehicle. This vehicle should not be modified with non
−genuine Lexus
products. Modification with non −genuine Lexus products
could af fect its performance, safety or durability, and may even
violate governmental regulations. In addition, damage or
performance problems resulting from the modification may not
be covered under warranty.
If you install any Genuine Accessories such as a bull −bar,
winch, etc., consult your Lexus dealer.
Installation of a mobile twoway radio system
As the installation of a mobile two −way radio system in your
vehicle could affect electronic systems such as the multiport
fuel injection system/sequential multiport fuel injection system,
cruise control system, anti −lock brake system, SRS airbag
system and seat belt pretensioner system, be sure to check
with your Lexus dealer for precautionary measures or special
instructions regarding installation.
Scrapping of your Lexus
The SRS airbag and seat belt pretensioner devices in your
Lexus contain explosive chemicals. If the vehicle is scrapped
with the airbags and seat belt pretensioners left as they are,
this may cause an accident such as a fire. Be sure to have the
systems of the SRS airbag and seat belt pretensioner removed
and disposed of by a qualified service shop or by your Lexus
dealer before you scrap your vehicle.

Finish
GAUGES, METERS AND SERVICE REMINDER INDICATORS
47
(e) Malfunction Indicator Lamp
This lamp comes on when the ignition key is turned to the
“ON” position and goes off after the engine starts. This
means that the warning light system is operating properly.
If the lamp remains on, or the lamp comes on while driving,
first check the followings.
 Empty fuel tank
If the fuel tank is empty, refuel immediately.
 Loose fuel tank cap
If the fuel tank cap is loose, securely tighten it.
These cases are temporary malfunctions. The malfunction
indicator lamp will go off after taking several driving trips.
If the lamp will not go off even after the several trips, contact
your Lexus dealer as soon as possible.
If the fuel tank is not empty or the fuel tank cap is not
loose ...
 There is a problem somewhere in the engine, emission
control system, electronic throttle control system, automatic
transmission electrical system or warning light system itself.
Contact your Lexus dealer as soon as possible to service the
vehicle.
If the engine speed does not increase with the accelerator
pedal depressed down, there may be a problem somewhere
in your electronic throttle control system. At this time, vibration may occur. However, if you depress the
accelerator pedal more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle checked by your
Lexus dealer as soon as possible.
Even if the abnormality of the electronic throttle control system
is corrected during low speed driving, the system may not be
recovered until the engine is stopped and the ignition key is
turned to “ACC” or “LOCK” position.
CAUTION
Be especially careful to prevent erroneous pedal
operation.
Emissions inspection and maintenance (I/M) programs
Your vehicle may not pass a state emission inspection if the
malfunction indicator lamp remains on. Contact your Lexus
dealer to check your vehicle’s emission control system and
OBD (On−Board Diagnostics) system before taking your
vehicle for the inspection.
For details, see “Emissions inspection and maintenance (I/M)
programs” on page 401.

STARTING AND DRIVING
298
To ensure that the threeway catalytic converter and
the entire emission control system operate properly,
your vehicle must receive the periodic inspections
required by the Lexus Maintenance Schedule. For
scheduled maintenance information, refer to the
“Owner’s Manual Supplement / Scheduled
Maintenance”.
ENGINE EXHAUST CAUTION
CAUTION
Avoid inhaling the engine exhaust. It contains
carbon monoxide, which is a colorless and odorless
gas. It can cause unconsciousness or even death.
 Make sure the exhaust system has no holes or loose
connections. The system should be checked from
time to time. If you hit something, or notice a change
in the sound of the exhaust, have the system checked
immediately.
 Do not run the engine in a garage or enclosed area
except for the time needed to drive the vehicle in or
out. The exhaust gases cannot escape, making this
a particularly dangerous situation.
 Do not remain for a long time in a parked vehicle with
the engine running. If it is unavoidable, however, do
so only in an unconfined area and adjust the heating
or cooling system to force outside air into the vehicle.
 Keep the back door closed while driving. An open or
unsealed back door may cause exhaust gases to be
drawn into the vehicle.

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
357

Avoid continuous speeding up and slowing down.
Stop−and−go driving wastes fuel.
 Avoid unnecessary stopping and braking. Maintain a
steady pace. Try to time the traf fic signals so you only need
to stop as little as possible or take advantage of through
streets to avoid traffic lights. Keep a proper distance from
other vehicles to avoid sudden braking. This will also
reduce wear on your brakes.
 Avoid heavy traffic or traffic jams whenever possible.
 Do not rest your foot on the brake pedal. This causes
premature wear, overheating and poor fuel economy.
 Maintain a moderate speed on highways. The faster you
drive, the greater the fuel consumption. By reducing your
speed, you will cut down on fuel consumption.
 Keep the front wheels in proper alignment. Avoid hitting
the curb and slow down on rough roads. Improper
alignment not only causes faster tire wear but also puts an
extra load on the engine, which, in turn, wastes fuel.
 Keep the bottom of your vehicle free from mud, etc. This
not only lessens weight but also helps prevent corrosion. 
Keep your vehicle tunedup and in top shape. A dirty air
cleaner, improper valve clearance, dirty plugs, dirty oil and
grease, brakes not adjusted, etc. all lower engine
performance and contribute to poor fuel economy. For
longer life of all parts and lower operating costs, keep all
maintenance work on schedule, and if you often drive under
severe conditions, see that your vehicle receives more
frequent maintenance. (For scheduled maintenance
information, please refer to the “Owner’s Manual
Supplement / Scheduled Maintenance”.)
CAUTION
Never turn off the engine to coast down hills. Your
power steering and brake booster will not function
without the engine running. Also, the emission control
system operates properly only when the engine is
running.

MAINTENANCE
395
MAINTENANCE REQUIREMENTS
Your Lexus vehicle has been designed to have fewer
maintenance requirements with longer service intervals to
save both your time and money. However, each regular
maintenance as well as day−to−day care is more important
than ever before to ensure smooth, trouble −free, safe, and
economical driving.
It is the owner’s responsibility to make sure the specified
maintenance, including general maintenance services, is
performed. Note that both the new vehicle and emission
control system warranties specify that proper maintenance
and care must be performed. See the “Owner’s Guide”,
“Owner’s Manual Supplement” or “Warranty Booklet” for
complete warranty information.
General maintenance
General maintenance items are those day −to−day care
practices that are important to your vehicle for proper
operation. It is the owner’s responsibility to ensure that the
general maintenance items are performed regularly.
These checks or inspections can be done either by yourself or
your Lexus dealer.
Scheduled maintenance
The scheduled maintenance items listed in the “Owner’s
Manual Supplement / Scheduled Maintenance” are those
required to be serviced at regular intervals. For details of your maintenance schedule, read the “Owner’s
Manual Supplement / Scheduled Maintenance”.
It is recommended that only genuine Lexus parts be used
for maintenance or for the repair of the emission control
system.
The owner may elect to use nonLexus supplied parts for
replacement purposes without invalidating the emission
control system warranty. However, use of replacement
parts which are not of equivalent quality may impair the
effectiveness of the emission control systems.
You may also elect to have maintenance, replacement, or
repair of the emission control devices and system
performed by any automotive repair establishment or
individual without invalidating this warranty. See
“Owner’s Guide”, “Owner’s Manual Supplement” or
“Warranty Booklet” for complete warranty information.
Where to go for service?
Lexus
technicians are well −trained specialists and are kept up
to date with the latest service information through technical
bulletins, service tips, and in −dealership training programs.
They are well informed about the operation of all the systems
on your vehicle.
You can be confident that your Lexus dealer’s service
department performs the best job to meet the maintenance
requirements of your vehicle − reliably and economically.

MAINTENANCE
397
Tire rotation
Rotate the
tires according to the maintenance schedule. (For
scheduled maintenance information, please refer to the
“Owner’s Manual Supplement / Scheduled Maintenance”.)
See page 434 for additional information.
Fluid leaks
Check underneath for leaking fuel, oil, water or other fluid after
the vehicle has been parked for a while. If you smell fuel fumes
or notice any leak, have the cause found and corrected
immediately.
Doors and engine hood
Check that all side doors and back door, operate smoothly and
all latches lock securely. Make sure the engine hood
secondary latch secures the hood when the primary latch is
released.
Vehicle interior
Items listed below should be checked regularly, e.g. while
performing periodic services, cleaning the vehicle, etc.
Lights
Make sure the headlights, stop lights, tail lights, turn signal
lights, and other lights are working. Check headlight aim.
Service reminder indicators and warning buzzers
Check that all service reminder indicators and warning buzzers
function properly. Steering wheel
Check that it has the
specified free play. Be alert for changes
in steering condition, such as hard steering, excessive free
play or strange noise.
Seats
Check that all front seat controls such as seat adjusters,
seatback recliner, etc. operate smoothly. Check that the head
restraints move up and down smoothly and that the locks hold
securely in any latched position. For folding −up second and
third seats, and detachable third seat, check that the latches
lock securely.
Seat belts
Check that the seat belt system such as buckles, retractors
and anchors operate properly and smoothly. Make sure the
belt webbing is not cut, frayed, worn or damaged.
Accelerator pedal
Check the pedal for smooth operation and uneven pedal ef fort
or catching.
Brake pedal
Check the pedal for smooth operation and the proper
clearance and free play. Check the brake booster function.
Brakes
At a safe place, check that the brakes do not pull to one side
when applied.

MAINTENANCE
399
Brake fluid level
Make sure the brake fluid level is correct. See page 430 for
additional information.
Engine oil level
Check the level on the dipstick with the engine turned off and
the vehicle parked on a level spot. See page 419 for
additional
information.
Power steering fluid level
Check the level through the reservoir. The level should be in
the “HOT” or “COLD” range depending on the fluid
temperature. See page 431 for additional information.
Exhaust system
If you notice any change in the sound of the exhaust or smell
exhaust fumes, have the cause located and corrected
immediately. (See “Engine exhaust caution” on page 298.)
DOES YOUR VEHICLE NEED REPAIRING?
Be on the alert for changes in performance and sounds, and
visual tip −offs that indicate service is needed. Some important
clues are:
 Engine missing, stumbling, or pinging
 Appreciable loss of power
 Strange engine noises
 A fluid leak under the vehicle (However, water dripping from
the air conditioning after use is normal.)
 Change in exhaust sound (This may indicate a dangerous
carbon monoxide leak. Drive with the windows open and
have the exhaust system checked immediately.)
 Flat−looking tires, excessive tire squeal when cornering,
uneven tire wear
 Vehicle pulls to one side when driving straight on a level
road
 Strange noises related to suspension movement
 Loss of brake effectiveness, spongy feeling brake pedal,
pedal almost touches floors, vehicle pulls to one side when
braking
 Engine coolant temperature continually higher than normal