Radiator Lexus IS300 2003 Basic Functions / LEXUS 2003 IS300 OWNER'S MANUAL (OM53439U)

IN CASE OF AN EMERGENCY
271
IF YOUR VEHICLE OVERHEATS
If your engine coolant temperature gauge indicates
overheating, if you experience a loss of power, or if you
hear a loud knocking or pinging noise, the engine has
probably overheated.
When the engine overheats
Pull safely off the road, stop the vehicle and turn on your
emergency flashers. Put the transmission in ºPº (automatic)
or neutral (manual) and apply the parking brake.
A: If steam is coming from your engine:
Turn off the engine. Leave the hood closed until there is no sign
of steam or coolant. Your engine could have been seriously
damaged already. Call your Lexus dealer for assistance.
CAUTION
To help avoid personal injury, keep the hood closed until
there is no steam. Escaping steam or coolant is sign of
very high pressure.
B: If no steam is coming from your engine:
Leave the engine running and turn off the air conditioning.
Check the following.
Is the cooling fan operating?
 Is the coolant in the acceptable range?
 Is the engine drive belt O.K.?
CAUTION
When the eng ine is running, keep hands and clothing
away from the moving fan and engine drive belt.
 Do not attempt to remove the radiator cap when the
engine and radiator are hot. Serious injury could
result from scalding hot fluid and steam blown out
under pressure.
If the cooling fan is not operating or the coolant is not in the
acceptable range, turn off the engine and call your Lexus
dealer.
If both conditions are O.K., after the engine coolant
temperature has cooled to normal, continue driving your
vehicle.
If the engine coolant temperature does not cool down, or your
vehicle overheats again, have it checked as soon as possible
by your Lexus dealer.
2003 IS300 from Aug. '02 Prod. (OM53439U)

INTRODUCTION
301
ENGINE COMPARTMENT OVERVIEW
1Battery
2Fuse box
3Engine oil filler cap
4Engine oil leveldipstick
5Brake fluid reservoir
6Washer fluid tank
7Power steering fluidreservoir
8Engine coolantreservoir
9Electric cooling fans
10Condenser
11Radiator
2003 IS300 from Aug. '02 Prod. (OM53439U)
SV61007a

INTRODUCTION
302
DO±IT±YOURSELF SERVICEPRECAUTIONS
If you perform maintenance yourself, be sure to follow the
correct procedure given in this Section.
You should be aware that improper or incomplete servicing
may result in operating problems.
Performing do±it±yourself maintenance during the warranty
period may affect your warranty coverage. Read the separate
Lexus Warranty statement for details and suggestions.
This Section gives instructions only for those items that are
relatively easy for an owner to perform. As explained in
Section 5, there are still a number of items that must be
performed by a qualified technician with special tools.
For information on tools and parts for do±it±yourself
maintenance, see ºParts and toolsº on page 303.
Utmost care should be taken when working on your vehicle to
prevent accidental injury. Here are a few precautions that you
should be especially careful to observe:
CAUTION

When the engine is running, keep hands, clothing,
and tools away from the moving fan and engine drive
belt. (Removing rings, watches, and ties is
advisable.)

Right after driving, the engine compartment ± the
engine, radiator, exhaust manifold and power
steering fluid reservoir, etc. ± will be hot. So be
careful not to touch them. Oil and other fluids may
also be hot.

Do not smoke, cause sparks or allow open flames
around fuel or the battery. Their fumes are
flammable.

Do not get under your vehicle with just the body jack
supporting it. Always use automotive jack stands or
other solid supports.

Be sure the ignition is off if you work near the electric
cooling fan or radiator grille. With the ignition on, the
electric cooling fan may automatically start to run if
the air conditioning is on and/or if the coolant
temperature is high.

Use eye protection whenever you work on or under
your vehicle where you may be exposed to flying or
falling material, fluid spray, etc.

Be extremely cautious when working on the battery.
It contains poisonous and corrosive sulfuric acid.

Warning: Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
2003 IS300 from Aug. '02 Prod. (OM53439U)

SECTION 6 ± 2
307
SERVICE PROCEDURES AND
SPECIFICATIONS
Engine
Specifications308
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
Fuel 311
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . \
. . . . . . . . . . . . . . . .
Fuel pump shut off system 313
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Facts about engine oil consumption 313
. . . . . . . . . . . . . . . . . . . . . . . .
Used engine oil 315
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . .
Checking the engine oil level 315
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the engine coolant level 319
. . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the radiator and condenser 320
. . . . . . . . . . . . . . . . . . . . . . .
Spark plugs 321
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . . .
2003 IS300 from Aug. '02 Prod. (OM53439U)

ENGINE
319
CHECKING THE ENGINE COOLANTLEVEL
SV62006

1Reservoir cap 2Upper line 3Lower line
Look at the see±through coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between theºFULLº and ºLº lines on the reservoir. If the
level is low, add ethylene±glycol type coolant for a proper
corrosion protection of aluminum components.
The coolant level in the reservoir will vary with engine
temperature. However, if the level is on or below the ºLº line,
add coolant. Bring the level up to the ºFULLº line.
Always use ethylene±glycol type coolant for a proper corrosion
protection of aluminum components. See information in the
next column. If the coolant level drops within a short time after replenishing,
there
may be a leak in the system. V isually check the radiator,
hoses, engine coolant filler cap, radiator cap and drain cock
and water pump.
If you can find no leak, have your Lexus dealer test the cap
pressure and check for leaks in the cooling system.
CAUTION
To prevent burning yourself, do not remove the radiator
cap when the engine is hot.
Coolant type selection
Use of improper coolants may damage your engine cooling
system. Your coolant must contain ethylene±glycol type
coolant for a proper corrosion protection of your engine that
contains aluminum components. We have used ºToyota
Genuine Long Life Coolantº in your Lexus vehicle. In order to
avoid technical problems, we strongly recommend using
ºToyota Genuine Long Life Coolantº or equivalent.
In addition to preventing freezing and subsequent damage to
the engine, this type of coolant will also prevent corrosion.
Further supplemental inhibitors or additives are neither
needed nor recommended.
Read the coolant container for information on freeze
protection. Follow the manufacturer's directions for how much
to mix with plain water (preferably demineralized water or
distilled water). The total capacity of the cooling system is
given on page 310.
2003 IS300 from Aug. '02 Prod. (OM53439U)

ENGINE
320We recommend to use 50% solution for your Lexus, to provide
protection
down to about ±35 C (±31F). When it is extremely
cold, to provide protection down to about ±50C (±58F), 60%
solution is recommended. Do not use more than 70% solution
for better coolant performance.
NOTICE
Do not use alcohol type antifreeze or plain water alone.
The engine cooling system is integral to maximizing
performance of your Lexus vehicle. In line with this, it is
strongly recommended that you use ºToyota Genuine Long
Life Coolantº for protecting the system, as it is an
ethylene±glycol based premium antifreeze coolant with
excellent corrosion protection properties that has been
specifically formulated for use in Lexus vehicles.
Please contact your Lexus dealer for further details of the
ºToyota Genuine Long Life Coolantº range.
CHECKING THE RADIATOR AND CONDENSER
If either of the above parts are extremely dirty or you are not
sure of their condition, take you vehicle to Lexus dealer.
CAUTION
To prevent yourself from burning, be careful not to
touch the radiator or co ndenser when the engine is hot.
NOTICE
To prevent damage to the radiator and condenser, do
not perform the work by yourself.
2003 IS300 from Aug. '02 Prod. (OM53439U)

ELECTRICAL COMPONENTS
346
No.FUSEAMPERECIRCUIT
1 D FR P/W20Power window system
2 TAIL10Tail lights, Side marker lights,
License plate lights,
Parking lights
3 GAUGE10
Back±up lights, Power window,
Gauges and meters,
Service reminder indicators and
buzzers,
Emergency flashers,
Windshield defogger,
Outside rear view mirror
defogger
4 DOOR20Door lock system
5 PANEL7.5
Instrument panel lights,
Seat heater, Cigarette lighter,
Automatic transmission system,
Traction control system,
Rear fog light, Ashtray light
6 WASHER15Windshield washer,
Headlight cleaner
7 STARTER7.5Starting system
8 FR DEF20Windshield wiper deicer
9 A/C10Air conditioning system
10 SEAT HTR15Seat heater
11 CIG15Cigarette lighter, Power outlet
12 S/ROOF30Moon roof
No.FUSEAMPERECIRCUIT
13 ECU±IG10
Radiator fan,
Anti±lock brake system,
Moon roof, Shift lock system,
Air conditioning system,
Door lock system,
Headlight beam level control,
Theft deterrent system
14 SRS±ACC10SRS system
15 STOP15Stop lights, Shift lock system,
Anti±lock brake system
16 WIPER25Windshield wipers
17 RADIONO.210Audio, Air conditioning,
Outside rear view mirror,
Shift lock system
18 DOOR DL15Power seat system
19 DOME7.5
Interior lights, Trunk light,
Vanity lights,
Ignition switch light, Map light,
Door courtesy lights
20 FR FOG15Fog lights
21 P FR P/W20Power window system
22 PWR
OUTLET15Power outlets
23 ECU±B27.5Theft deterrent system,
Door lock system
24 D RR P/W20Power window system
25 MIR HTR15Outside rear view mirror
2003 IS300 from Aug. '02 Prod. (OM53439U)