cooling Lexus IS300 2003 Basic Functions / LEXUS 2003 IS300 (OM53439U) User Guide

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)

ENGINE
310± COOLING SYSTEM
Capacity
7.5 L (7.9 qt., 6.6 lmp.qt.)
Coolant typeºToyota Genuine Long Life Coolantº or equivalent
With ethylene±glycol type coolant for a proper corrosion protection o\
f
aluminum components
Do not use alcohol type antifreeze or plain water alone.
NOTE:
ºToyota Genuine Long Life Coolantº is filled in your Lexus vehicle. In order \
to avoid technical problems, we strongly recommend using
ºToyota Genuine Long Life Coolantº or equivalent. Please contact your \
Lexus dealer for further details.
± FUEL
Fuel type
Only UNLEADED
Octane rating91 (Research octane number 96) or higher
± IGNITION SYSTEMSpark plug ± Make DENSO ± Gap
SK16R±P11
1.1 mm (0.043 in.)
± ELECTRICAL SYSTEM
Battery ± Open voltage at 20 C (68F):
Charging rates
12.7 V Fully charged
12.3 V Half charged
11.9 V Discharged
[Voltage that is checked 20 minutes after the key is removed with all the
lights turned off]
5A max.
2003 IS300 from Aug. '02 Prod. (OM53439U)

ENGINE
313
FUEL PUMP SHUT OFF SYSTEM
The fuel pump shut off system stops supplying fuel to the
engine to minimize the risk of fuel leakage when the engine
stalls or an airbag inflates upon collision. To restart the engine
after the fuel pump shut off system activates, turn the ignition
switch to ºACCº or ºLOCKº once and start it.
CAUTION
Inspect the ground under the vehicle before restarting
the engine. If you find that liquid has leaked onto the
ground, it is the fuel system has been damaged and it is
in need of repair. In this case, do not restart the engine.
FACTS ABOUT ENGINE OILCONSUMPTION
Functions of engine oil
Engine oil has the primary function of lubricating and cooling
the inside of the engine, and plays a major role in maintaining
the engine in proper working order.
Engine oil consumption
It is normal that an engine should consume some engine
oil during normal engine operation. The causes of oil
consumption in a normal engine are as follows.
Oil is used to lubricate pistons, piston rings and cylinders.
A thin film of oil is left on the cylinder wall when a piston
moves downwards in the cylinder. High negative pressure
generated when the vehicle is decelerating sucks some of
this oil into the combustion chamber. This oil as well as
some part of the oil film left on the cylinder wall is burned by
the high temperature combustion gases during the
combustion process.
 Oil is also used to lubricate the stems of the intake valves.
Some of this oil is sucked into the combustion chamber
together with the intake air and is burned along with the fuel.
High temperature exhaust gases also burn the oil used to
lubricate the exhaust valve stems.
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)

CHASSIS
340
NOTICE
Do not attempt to use a tire chain on the compact sparetire, as it may result in damage to the vehicle as well asthe tire.
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bends, cracks or heavy
corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, the tire may slip off the
wheel or cause loss of handling control.
Replacement with used wheels is not recommended as they
may have been subjected to rough treatment or high mileage
and could fail without warning. Also, bent wheels which have
been straightened may have hidden structural damage and
therefore should not be used. Never use an inner tube in a
leaking wheel which is designed for a tubeless tire.
Wheel selection
When replacing wheels, care should be taken to ensure
that they are equivalent to those removed in load capacity,
diameter, rim width, and offset.
Correct replacement wheels are available at your Lexus
dealer.
A wheel of a different size or type may adversely affect
handling, wheel and bearing life, brake cooling,
speedometer/odometer calibration, stopping ability, headlight
aim, bumper height, vehicle ground clearance, and tire or snow
chain clearance to the body and chassis.
2003 IS300 from Aug. '02 Prod. (OM53439U)