radiator cap 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

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)