Page 324 of 389

ENGINE
311
FUEL
Fuel type
Your vehicle must use only unleaded gasoline.
To help prevent gas station mixups, your Lexus has a smaller
fuel tank opening. The special nozzle on pumps with unleaded
fuel will fit it, but the larger standard nozzle on pumps with
leaded gas will not.
At a minimum, the gasoline you use should meet the
specifications of ASTM D4814 in the U.S.A. and CGSB
3.5±M93 in Canada.
NOTICE
Do not use leaded gasoline. Use of leaded gasoline will cause the three±way catalytic converter to lose itseffectiveness and the emission control system tofunction improperly. Also, this can increasemaintenance costs.
Octane rating
Select premium unleaded gasoline with an Octane Rating
of 91 (Research Octane Number 96) or higher for optimum
engine performance. However, if such premium type
cannot be obtained, you may temporarily use unleaded
gasoline with an Octane Rating as low as 87 (Research
Octane Number 91). Use of unleaded fuel with an octane number or rating lower
than stated above will cause persistent heavy knocking. If
severe, this will lead to engine damage.
If your engine knocks ...
If you detect heavy knocking even when using the
recommended fuel, or if you hear steady knocking while
holding a steady speed on level roads, consult your Lexus
dealer.
However, occasionally, you may notice light knocking for a
short time while accelerating or driving up hills. This is normal
and there is no need for concern.
Gasoline containing detergent additives
Lexus recommends the use of gasoline that contains
detergent additives to avoid build±up of engine deposits.
However, all gasoline sold in the U.S. contains detergent
additives to keep clean and/or clean intake systems.
Quality gasoline
Automotive manufacturers in the U.S., Europe and Japan
have developed a specification for quality fuel named
World±Wide Fuel Charter (WWFC) that is expected to be
applied world wide. The WWFC consists of three
categories
that depend on required emission levels. In the
U.S., category 3 has been adopted. The WWFC improves
air quality by providing for better emissions in vehicle
fleets, and customer satisfaction through better vehicle
performance.
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ENGINE
316
SV62002
1Add oil 2O.K. 3Too full
4. Pull the dipstick out and look at the oil level while holding a
rag under the end. If it is between the low level mark ( 4 ) and
the full level mark ( 5 ), it is O.K.
NOTICE
Be careful not to drop the engine oil on the vehicle
components.
SV62008
If the oil level is below or only slightly above the low level
mark, add engine oil of the same type as already in the
engine.
Remove the oil filler cap and add engine oil a little at a time,
checking the dipstick. We recommend that you use a funnel
when adding oil.
The approximate quantity of oil needed to fill between the low
level mark and the full level mark on the dipstick is indicated
below for reference.
When the level reaches within the correct range, return the
filler cap and turn the cap clockwise until you hear a click.
Oil quantity. L (qt., lmp. qt.) 1.8 (1.9, 1.6)
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CHASSIS
329
CHECKING BRAKE FLUID
SV63001
To check the fluid level, simply look at the see±through
reservoir. The level should be between the ºMAXº and
ºMINº lines on the tank.
It is normal for the brake fluid level to go down slightly as the
brake pads wear or when the fluid level in the accumulator is
high.
If the reservoir needs frequent refilling, it may indicate a
serious mechanical problem.
If the level is low, add FMVSS No.116 DOT 3 or SAE J1703
brake fluid to the brake reservoir.
Refilling brake fluid:
1. Turn the ignition switch off.
2. Depress the brake pedal more than 40 times.
3. Remove the reservoir cap by hand. Add brake fluid up to
the ºMAXº line.If you do not follow the procedure above, the reservoir may
overflow.
Use only newly opened brake fluid. Once opened, brake fluid
absorbs
moisture from the air, and excess moisture can cause
a dangerous loss of braking efficiency.
CAUTION
Take care when filling the reservoir because brake fluid
can harm your hands or eyes and damage painted
surfaces. If fluid gets in your eyes, flush your eyes with
clean water immediately. If you still feel uncomfortable
with your eyes, go to the doctor.
NOTICE
If you spill some of the fluid, be sure to wipe it off to prevent it from damaging the parts or paintwork.
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CHASSIS
340
NOTICE
Do not attempt to use a tire chain on the compact sparetire, as it may result in damage to the vehicle as well asthe tire.
REPLACING WHEELS
When to replace your wheels
If you have wheel damage such as bends, cracks or heavy
corrosion, the wheel should be replaced.
If you fail to replace damaged wheels, the tire may slip off the
wheel or 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 removed 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.
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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
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\
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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
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ELECTRICAL COMPONENTS
348
CHECKING BATTERY CONDITION
Precautions
CAUTION
BATTERY PRECAUTIONS
The battery produces flammable and explosive
hydrogen gas.
Do not cause a spark by contacting the battery
terminals with tools.
Do not smoke or light a match near the battery.
The electrolyte contains poisonous and corrosive
sulfuric acid.
Avoid contact with eyes, skin or clothes.
Never inhale or swallow electrolyte.
Wear protective safety glasses when working near
the battery.
Keep children away from the battery.
EMERGENCY MEASURES
If electrolyte gets in your eyes, flush your eyes with
clean water for at l east 15 minutes and get immediate
medical attention. If possible, continue to apply
water with a sponge or cloth while traveling to the
medical office.
If electrolyte gets on your skin, thoroughly wash the
contacted area. If you feel a pain or burn, get medical
attention immediately.
If electrolyte gets on your clothes, there is a
possibility of its soaking through to your skin, so
immediately take off the exposed clothing and follow
the procedure above, if necessary.
If you accidentally swallow electrolyte, drink a large
quantity of water or milk. Follow with milk of
magnesia, beaten raw egg or vegetable oil. Then go
immediately for emergency help.
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.
2003 IS300 from Aug. '02 Prod. (OM53439U)