2003 Lexus IS300 maintenance

1.
FOREWORD
i
Congratulations on your selection of this Lexus. In Lexus vehicles we ha\
ve invested all our engineering and design resources; a
ll
the know± how we have gained in over 60 years of making automobiles; the\
highest motivation of our most talented employees; and
our tradition of incessant striving toward ever greater quality.
This Owner's Manual explains the features of your new Lexus. Please read it and fol\
low the instructions carefully so that you can
enjoy many years of safe motoring.
When it comes to service, remember that your Lexus dealer knows your vehicle bes\
t and is interested in your complete satisfaction.
Your Lexus dealer will provide quality maintenance and any other assistan\
ce you may require.
If there is not a Lexus dealer near you, or you need emergency assistanc\
e for any reason, please call the following number:
U.S. OWNERS

When traveling in the U.S. mainland or Canada:
Lexus Roadside Assistance 1±800±25±LEXUS (Toll±Free)
(1±800±255±3987)

HAWAII:
Lexus Customer Service Assistance 1±800±25±LEXUS (Toll±Free)
(1±800±255±3987)
CANADIAN OWNERS
When traveling in Canada or the U.S. mainland:
Lexus Roadside Assistance/Customer Service 1±800±26±LEXUS (Toll±Free)
(1±800±265±3987)
Please leave this Owner's Manual in this vehicle at the time of resale. The next owner will nee\
d this information also.
All information and specifications in this manual are current at the time o\
f printing. However, because of the Lexus policy
of continual product improvement, we reserve the right to make changes a\
t any time without notice.
Please note that this manual applies to all models and explains all equi\
pment, including options. Therefore, you may find
some explanations for equipment not installed on your vehicle.
2003 IS300 from Aug. '02 Prod. (OM53439U)

2.
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 ºOwner's Guideº,
ºOwner's Manual Supplementº or ºWarranty Bookletº.
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, pl ease refer to the ºOwner's Manual
Supplement/Scheduled Maintenanceº.
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 re sulting from the modification may not
be covered under warranty.
Spark ignition system of your Lexus
The spark ignition system in your Lexus meets all
requirements of the Canadian Interference±Causing
Equipment Standard.
Installation of a mobile two±way 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 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.
2003 IS300 from Aug. '02 Prod. (OM53439U)

3.
HOW TO USE THIS MANUAL
iii
HOW TO USE THIS MANUAL
The contents of this manual are explained briefly on this
page to help you make the best use of the manual. Please
read this page and the rest of the Owner's Manual
carefully to make sure you fully understand the operation
of your vehicle.
This will help you enjoy safe and comfortable driving.
TABLE OF CONTENTS
The table of contents and the pictorial index provide easy
reference to the appropriate pages.
BASIC OPERATION ± QUICK REFERENCE
Operation of basic equipment is briefly explained in an easily
understandable way for quick reference.
SECTION 1 ± INSTRUMENTS AND CONTROLS
The vehicle's equipment is divided into the 7 groups listed
below. Use of the equipment is explained, including any points
you should pay particular attention to.
1. Keys and doors
2. Switches
3. Gauges, meters and service reminder indicators
4. Interior equipment
5. Exterior equipment
6. Comfort adjustment
7. Theft deterrent
SECTION 2 ± AIR CONDITIONING AND AUDIO
The features of the vehicle's air conditioning and audio are
explained in detail. Be sure to read this section so that you can
make full use of them.
SECTION 3 ± STARTING AND DRIVING
Starting the engine, driving, stopping, operation of features
affecting vehicle handling, hints on vehicle safety and safe
driving techniques are all explained. Please read everything
in this section, and remember ± drive safely!
SECTION 4 ± IN CASE OF AN EMERGENCY
This section explains what to do in the event of an urgent
situation such as the engine not starting or getting a flat tire,
etc. If such a problem occurs, check the contents of this
Owner's Manual and follow the instructions given.
SECTION 5 ± MAINTENANCE
This section explains the importance of regular maintenance.
Regular and periodic inspection and maintenance of your
Lexus will help to keep your vehicle in its best condition.
SECTION 6 ± SERVICE PROCEDURES AND
SPECIFICATIONS
Simple maintenance procedure and service data are provided
here for your reference should you wish to perform inspection
and maintenance yourself.
2003 IS300 from Aug. '02 Prod. (OM53439U)

GAUGES, METERS AND SERVICE REMINDER INDICATORS
49
(g) Low Engine Oil Level Warning Light
This light warns that the engine oil level is too low. Add oil as
soon as possible. (For instructions, see ºChecking the engine
oil levelº on page 315.)
While driving on steep inclines or rough roads which causes
the vehicle to substantially sway or on curves, this light may
come on due to the movement of engine oil in the engine.
In normal conditions, due to engine oil consumption, this light
may come on earlier than the specified service interval of the
scheduled maintenance. This is because the engine oil is
consumed to the low level within the scheduled maintenance
interval and does not indicate a problem. (For detailed
information, see ºFacts about engine oil consumptionº on page
313.)
NOTICE
Continued engine operation with low engine oil will damage the engine.
(h) Malfunction Indicator Lamp
This lamp comes on when the ignition key is turned to the
ºONº 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 this lamp comes on and the engine speed does not increase
with the accelerator pedal depressed down to about the middle
position, there may be a problem somewhere in your electronic
throttle control system.
At this time, if you depress the accelerator pedal more firmly
and slowly, you can drive your vehicle at low speeds. Have
your Lexus 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 ºACCº or ºLOCKº position.
2003 IS300 from Aug. '02 Prod. (OM53439U)

GAUGES, METERS AND SERVICE REMINDER INDICATORS
50
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 ºEmissions Inspection and Maintenance (I/M)
programsº on page 297.
(i) ºABSº Warning Light
The light comes on when the ignition key is turned to the ºONº
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 ºABSº warning light is on (and the brake system
warning light is off), the anti±lock brake system, the brake
assist system, the traction control system and/or the vehicle
skid control system do not operate, but the brake system still
operates conventionally.
When the ºABSº warning light is on (and the brake system
warning light is off), the anti±lock brake system and/or the
traction control system do/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 ºONº 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 ºABSº 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.
(j) Open Door Warning Light
This light remains on until all the doors are completely closed.
2003 IS300 from Aug. '02 Prod. (OM53439U)

AIR CONDITIONING
188
SV21015
2. Remove the cover and take out the air filter
If it is dirty, it should be replaced. To maintain the air
conditioning efficiency, replace the air filter according to the
maintenance schedule. (For scheduled maintenance
information, please refer to the ºOwner's Manual Supplement
/ Scheduled Maintenanceº.)
INFORMATION
The air filter should be installed properly in position.The use of air conditioning with the air filter removedmay cause deteriorated dustproof performance andthen affect air conditioning performance.
(d) Operating tips
 To help cool down the interior after parking in the hot sun,
drive for the first few minutes with the windows open. After
the excess heat has blown away, close the windows.
 Make sure the air inlet grilles in front of the windshield are
not blocked by leaves or other obstructions.
 If air flow control is not satisfactory, check the dashboard
vents. (See ºCenter ventsº and ºSide ventsº.)
 On humid days, do not blow cold air on the windshield. The
windshield could fog up because of the difference in air
temperature on the inside and outside of the windshield.
 Keep the area under the front seats clear to allow air to
circulate throughout the vehicle.
 On cold days, set the fan speed selector to adjust the fan
speed high for a minute to help clear the intake ducts of
snow or moisture. This can reduce the amount of fogging
on the windows.
 When driving on dusty roads, close all windows. If dust
thrown up by the vehicle is still drawn into the vehicle after
closing the windows, it is recommended that the air intake
control button be left to the OUTSIDE AIR mode and the fan
speed control dial be turned to anywhere except the ºOFFº
button.
 If following another vehicle on a dusty road, or driving in
windy and dusty conditions, it is recommended that the air
intake control button be temporarily pressed in to the
RECIRCULATED AIR m ode, which will close off the outside
passage and prevent outside air and dust from entering the
vehicle interior.
2003 IS300 from Aug. '02 Prod. (OM53439U)

STARTING AND DRIVING
225

To ensure that the three±way catalytic converter and
the entire emission control system operate properly,your vehicle must receive the periodic inspectionsrequired by the Lexus Maintenance Schedule . Forscheduled maintenance information, refer to theºOwner's Manual Supplement/ScheduledMaintenance º.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 trunk lid or back door closed while driving.
An open or unsealed trunk lid or back door may
cause exhaust gases to be drawn into the vehicle.
2003 IS300 from Aug. '02 Prod. (OM53439U)

DRIVING TIPS
264

Keep your vehicle tuned±up 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 ºOwner's Manual
Supplement / Scheduled Maintenanceº.)
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.
2003 IS300 from Aug. '02 Prod. (OM53439U)