1999 LEXUS SC300 cooling

ENGINE
348
Look at the see±through coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between theºFULLº and ºLOWº 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 ºLOWº
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. Visually
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.

ENGINE
349
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. Use ºToyota 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 331.
We recommend to use 50% solution for your Lexus, to
provide protection down to about ±35C (±31F). When it is
extremely cold, to provide protection down to about ±50 C
(±58 F), 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.
CHECKING THE ENGINE FAN FLUID (SC400 ONLY)
Park the vehicle at a level spot and look at the see±thr ough
reservoir. If necessary, add automatic transmission fluid
DEXRON
 II or III.

CHASSIS
372
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bending, cracks or
heavy corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, a tire may slip off a
wheel or they may 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 rem oved 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.
ALUMINUM WHEEL PRECAUTIONS
After driving your vehicle the first 1600 km (1000 miles),
check that the wheel nuts are tight.
 If you have rotated, repaired, or changed your tires, check
that the wheel nuts are still tight after driving 1600 km
(1000 miles).
 When using tire chains, be careful not to damage the
aluminum wheels.
 Use only the Lexus wheel nuts and wrench designed for
your aluminum wheels.
 When balancing your wheels, use only Lexus balance
weights or equivalent and a plastic or rubber hammer.
 As with any wheel, periodically check your aluminum
wheels for damage. If damaged, replace immediately.

ELECTRICAL COMPONENTS
378
No.FUSEAMPERECIRCUIT
11RADIONO.27.5Radio, cassette tape player,
compact disc player, power
antenna, power rear view mirrors
12TAIL7.5Tail lights, parking lights, side
marker lights, license plate lights
13ECU±IG15
Cruise control system, power
steering control system, shift lock
system, anti±lock brake system,
SRS airbag system, power door
lock system, preset steering system,
traction control system,
electronically controlled
hydraulic±driven cooling system,
passenger 's seat control system
14GAUGE10
Gauges and meters, service
reminder indicators and warning
buzzers (except discharge and open
door warning lights), back±up
lights, electronically controlled
automatic transmission system,
automatic transmission overdrive
system, headlight
15ECU±B15SRS airbag system, power rear
view mirrors
16OBD7.5On±board diagnosis system
17FOG15Fog lights
18SEAT±HT R15Seat heater