Page 331 of 389

ENGINE
318
Oil identification marks
SOIL11
API Service SymbolILSAC Certification Mark
Either or both API registered marks are added to some oil
containers to help you select the oil you should use.
The API Service Symbol is located anywhere on the outside
of the container.
The top portion of the label shows the oil quality by API
(American Petroleum Institute) designation such as SL.
The center portion of the label shows the SAE viscosity
grade such as SAE 5W±30. ºEnergy±Conservingº, shown
in the lower portion, indicates that the oil has fuel±saving
capabilities.
The ILSAC (International Lubricant Standardization and
Approval Committee) Certification Mark is displayed on the
front of the container. To ensure excellent lubrication performance for your engine,
the ºToyota Genuine Motor Oilº range is available, which has
been specifically tested and approved for all Lexus engines.
Please contact your Lexus dealer for further details of the
ºToyota Genuine Motor Oilº range.
2003 IS300 from Aug. '02 Prod. (OM53439U)
Page 336 of 389

SECTION 6 ± 3
323
SERVICE PROCEDURES AND
SPECIFICATIONS
Chassis
Specifications324
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
Checking brake fluid 329
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
.
Checking power steering fluid 330
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking tire pressure 331
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rotating tires 333
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . . .
Checking and replacing tires 335
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installing snow tires and chains 338
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing wheels 340
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . .
Aluminum wheel precautions 341
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Suspension and chassis 342
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2003 IS300 from Aug. '02 Prod. (OM53439U)
Page 349 of 389

CHASSIS
336If a tire often goes flat or cannot be properly repaired due to the
size or location of a cut or other damage, it should be replaced.
If you are not sure, consult with your Lexus dealer.
If an air loss occurs while driving, do not continue driving with
a deflated tire. Driving even a short distance can damage a tire
beyond repair.
Any tires which are over 6 years old must be checked by
a qualified technician even if damage is not obvious.
Tires deteriorate with age even if they have never or seldom
been used.
This also applies to the spare tire and tires stored for future
use.
Uniform tire quality grading
This information has been prepared in accordance with
regulations
issued by the National Highway T raffic Safety
Administration of the U.S. Department of Transportation.
It provides the purchasers and/or prospective purchasers
of Lexus vehicles with information on uniform tire quality
grading.
Your Lexus dealer will help answer any questions you may
have as you read this information.
DOT quality grades ± All passenger vehicle tires must
conform to Federal Safety Requirements in addition to
these grades. Quality grades can be found where
applicable on the tire sidewall between tread shoulder and
maximum section width. For example: Treadwear 200
Traction AA Temperature A
Treadwear ± The treadwear grade is a comparative rating
based on the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and a half (1 ± 1/2)
times as well on the government course as a tire graded 100.
The relative performance of tires depends upon the actual
conditions of their use, however, and may depart significantly
from the norm due to variations in driving habits, service
practices and differences in road characteristics and climate.
Traction AA, A, B, C ± The traction grades, from highest to
lowest, are AA, A, B and C, and they represent the tire's ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of asphalt
and concrete. A tire marked C may have poor traction
performance.
2003 IS300 from Aug. '02 Prod. (OM53439U)
Page 356 of 389
SECTION 6 ± 4
343
SERVICE PROCEDURES AND
SPECIFICATIONS
Electrical components
Specifications344
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
. . . . . .
Checking battery condition 348
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery recharging precautions 350
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking and replacing the blade type fuses 351
. . . . . . . . . . . . . . . .
Checking the cartridge type fuses 353
. . . . . . . . . . . . . . . . . . . . . . . . . .
Adding washer fluid 354
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
.
Checking the headlight aim 355
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing light bulbs 356
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
2003 IS300 from Aug. '02 Prod. (OM53439U)
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)
Page 360 of 389

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)
Page 374 of 389
SECTION 6 ± 5
361
SERVICE PROCEDURES AND
SPECIFICATIONS
Body
Specifications (Sedan)362
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications (SportCross) 363
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Protecting your vehicle from corrosion 364
. . . . . . . . . . . . . . . . . . . . . .
Washing and waxing 365
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
Cleaning the interior 367
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
.
Rain clearing mirrors 370
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
2003 IS300 from Aug. '02 Prod. (OM53439U)