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AIR CONDITIONING
188
SV21015
2. Remove the cover and take out the air filter
If it is dirty, it should be replaced. To maintain the air
conditioning efficiency, replace the air filter according to the
maintenance schedule. (For scheduled maintenance
information, please refer to the ºOwner's Manual Supplement
/ Scheduled Maintenanceº.)
INFORMATION
The air filter should be installed properly in position.The use of air conditioning with the air filter removedmay cause deteriorated dustproof performance andthen affect air conditioning performance.
(d) Operating tips
To help cool down the interior after parking in the hot sun,
drive for the first few minutes with the windows open. After
the excess heat has blown away, close the windows.
Make sure the air inlet grilles in front of the windshield are
not blocked by leaves or other obstructions.
If air flow control is not satisfactory, check the dashboard
vents. (See ºCenter ventsº and ºSide ventsº.)
On humid days, do not blow cold air on the windshield. The
windshield could fog up because of the difference in air
temperature on the inside and outside of the windshield.
Keep the area under the front seats clear to allow air to
circulate throughout the vehicle.
On cold days, set the fan speed selector to adjust the fan
speed high for a minute to help clear the intake ducts of
snow or moisture. This can reduce the amount of fogging
on the windows.
When driving on dusty roads, close all windows. If dust
thrown up by the vehicle is still drawn into the vehicle after
closing the windows, it is recommended that the air intake
control button be left to the OUTSIDE AIR mode and the fan
speed control dial be turned to anywhere except the ºOFFº
button.
If following another vehicle on a dusty road, or driving in
windy and dusty conditions, it is recommended that the air
intake control button be temporarily pressed in to the
RECIRCULATED AIR m ode, which will close off the outside
passage and prevent outside air and dust from entering the
vehicle interior.
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AIR CONDITIONING
189
Heating
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± To the desired temperature
Air intake ± OUTSIDE AIR
For manual operation ±Fan speed ± To the desired fan speed
Temperature ± Towards WARM (to the right)
Air intake ± OUTSIDE AIR
Air flow ± FLOOR
For quick heating, select RECIRCULATED AIR for a few
minutes. To keep the windows from fogging, select
OUTSIDE AIR after the vehicle interior has been warmed.
Push the ºA/Cº button on for dehumidified heating.
Choose floor/windshield air flow to heat the vehicle interior
while defrosting or defogging the windshield. Air conditioning
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± To the desired temperature
Air intake ± OUTSIDE AIR
For manual operation ±Fan speed ± To the desired fan speed
Temperature ± Towards COLD (to the left)
Air intake ± OUTSIDE AIR
Air flow ± PANEL
For quick cooling, select RECIRCULATED AIR for a few
minutes.
Ventilation
For best results, set controls to:
For automatic operation ±
Set the air flow control dial and the fan speed control
dial to ºAUTOº position.
Temperature ± Towards low temperature
Air intake ± OUTSIDE AIR
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Page 239 of 389
STARTING AND DRIVING
226
To allow proper operation of your vehicle's
ventilation system, keep the inlet grilles in front of the
windshield clear of snow, leaves, or other
obstructions.
If you smell exhaust fumes in the vehicle, drive with
the windows open and the trunk lid or back door
closed. Have the cause immediately located and
corrected.BEFORE STARTING THE ENGINE
1. Check the area around the vehicle before entering it.
2. Adjust seat position, seatback angle, head restraint height
and steering wheel angle.
3. Adjust the inside and outside rear view mirrors.
4. Lock all doors.
5. Fasten seat belts.
Remember to check that the service reminder indicators
function when turning the key to ºONº, and check the fuel
gauge to see that you have sufficient fuel.
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DRIVING TIPS
261
Check the electronic ignition system for loose
connections or obvious damage.
Keep the door locks from freezing.
Squirt
lock de±icer or glycerine into the locks to keep them from
freezing.
Use a washer fluid containing an antifreeze solution.
This product is available at your Lexus dealer and most auto
parts stores. Follow the manufacturer's directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any other substitute because it may damage your vehicle's paint.
Do not use your parking brake when there is a possibility
it could freeze.
When parking, put the transmission into ºPº (automatic) or into
first or reverse (manual) and block the front wheels. Do not use
the parking brake, or snow or water accumulated in and around
the parking brake mechanism may freeze the parking brake,
making it hard to release.
Keep ice and snow from accumulating under the fenders.
Ice and snow built up under your fenders can make steering
difficult. During bad winter driving, stop and check under the
fenders occasionally. Depending on where you are driving, we recommend you
carry some emergency equipment.
Some of
the things you might put in the vehicle are tire chains,
window scraper, bag of sand or salt, flares, small shovel,
jumper cables, etc.
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Page 303 of 389
IN CASE OF AN EMERGENCY
290
IF YOU LOSE YOUR KEYS ORLOCK YOURSELF OUT
You can purchase a new key at your Lexus dealer if you
can give them the key number and master key.
Even if you lose only one key, contact your Lexus dealer to
make a new key. If you lose all your master keys, you cannot
make new keys; the whole engine immobiliser system must be
replaced.
See the suggestion given in ºKeysº on page 8.
You can use the wireless remote control system with the new
key. Contact your Lexus dealer for detailed information.
If your keys are locked in the vehicle and you cannot get a
duplicate, many Lexus dealers can still open the door for you,
using their special tools. If you must break a window to get in,
we suggest breaking the smallest side window because it is the
least expensive to replace. Be extremely cautious to avoid
cuts from the glass.
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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 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
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ELECTRICAL COMPONENTS
347
No.FUSEAMPERECIRCUIT
26 MPX±B10
Power window system,
Air conditioning,
Gauges and meters,
Theft deterrent system
27 P RR P/W20Power window system
28 SRS±B7.5SRS system, Door lock system
29 TV7.5Television
30 OBD7.5On±board diagnosis system
31 IGN7.5
SRS system,
Multiport fuel injection
system/sequential multiport fuel
injection system,
Cruise control system
32 ECU±B120
Theft deterrent system,
Door lock system,
Interior light, Trunk light,
Vanity light, Ignition switch light,
Map light, Door courtesy lights,
Power window system,
Air conditioning,
Gauges and meters
33 ALT±S7.5Charging system
34 ETCS15Electronic throttle control
system
35 AM220
Starting system, SRS system,
Multiport fuel injection
system/sequential multiport fuel
injection system, Cruise control
system
36 HORN10Horn
No.FUSEAMPERECIRCUIT
37 RADIONO.120Audio
38 TURN±HAZ15Turn signal lights
39 EFI25
Multiport fuel injection
system/sequential multiport fuel
injection system,
Emission control system,
Engine immobiliser system
40 DRL NO.230Daytime running light system
41 DRL NO.17.5Daytime running light system
42 H±LP L LW R15Left±hand headlight
(low beam), Fog lights
43 H±LP R LW R15Right±hand headlight
(low beam)
44 ABS27.5Anti±lock brake system
45 SPARESpare fuse
46 SPARESpare fuse
47 SPARESpare fuse
48 H±LP LUPR10Left±hand headlight
(high beam)
49 H±LP R UPR10
Right±hand headlight
(high beam),
Service reminder indicators and
buzzers
2003 IS300 from Aug. '02 Prod. (OM53439U)