Page 204 of 389
AIR CONDITIONING
191
For manual operation ±
Fan speed ± To the desired fan speed
Temperature ± Towards WARM (to the right)
Air intake ± OUTSIDE AIR
Air flow ± WINDSHIELD
Set the air flow control dial to the windshield or floor/windshield
position turns on the defrosting function with the purpose of
clearing the front view.
When turning the air flow selector to windshield position, the
air intake selects FRESH automatically. This is to clean up the
front view more quickly.
If you want to return the setting to RECIRCULATE mode, press
the air intake selector button once again.
Press the ºA/Cº button for dehumidified heating or cooling. This
setting clears the front view more quickly.
To heat the vehicle interior while defrosting the windshield,
choose floor/windshield air flow.
Center vents
SV21026
The center vents may be opened or closed as shown.
Side vents
SS21019
The side vents may be opened or closed as shown.
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Page 205 of 389
AIR CONDITIONING
192
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SECTION 2 ± 2
193
AIR CONDITIONING AND AUDIO
Audio
Audio system194
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . .
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Page 233 of 389
AUDIO
220Caring for your compact disc player and discs
Your compact disc player is intended for use with 12 cm (4.7
in.) discs only.
Extremely high temperature can keep your compact disc
player from working. On hot days, use air conditioning to
cool the vehicle interior before you listen to a disc.
Bumpy roads or other vibrations may make your compact
disc player skip.
If moisture gets into your compact disc player, you may not
hear any sound even though your compact disc player
appears to be working. Eject all discs from the player and
wait until the player dries.
CAUTION
Compact disc players use an invisible laser beam which
could cause hazardous radiation exposure if directed
outside the unit. Be sure to operate the player correctly.
20L037
Use only compact discs marked as shown above. The
following products may not be playable on your compact
disc player.
Copy±protected CD
CD±R (CD±Recordable)
CD±RW (CD±Re±writable)
CD±ROM
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Page 284 of 389

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.
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Page 309 of 389

MAINTENANCE
296
DOES YOUR VEHICLE NEEDREPAIRING?
Be on the alert for changes in performance and sounds, and
visual tip±offs that indicate service is needed. Some important
clues are:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A fluid leak under the vehicle (however, water dripping from
the air conditioning after use is normal.)
Change in exhaust sound (This may indicate a dangerous
carbon monoxide leak. Drive with the windows open and
have the exhaust system checked immediately.)
Flat±looking tires, excessive tire squeal when cornering,
uneven tire wear
Vehicle pulls to one side when driving straight on a level
road
Strange noises related to suspension movement
Loss of brake effectiveness, spongy feeling brake pedal,
pedal almost touches floors, vehicle pulls to one side when
braking
Engine coolant temperature continually higher than normal
If you notice any of these clues, take your vehicle to your Lexus
dealer as soon as possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the vehicle unchecked. It
could result in serious vehicle damage and possibly
personal injury.
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Page 315 of 389

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.
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Page 359 of 389

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)