2002 Lexus IS300 Ignition switch

STARTING AND DRIVING
244
VEHICLE SKID CONTROL SYSTEM
The vehicle skid control system helps provide integrated
control of the systems such as an anti±lock brake system,
brake assist system, traction control, engine control, etc.
This system automatically controls the output of the
brakes or engine to help prevent the vehicle from skidding
when cornering on a slippery road surface or abrupt
steering wheel operation occurs.
SV31037

Slip indicator light
If the vehicle is going to skid during driving, the slip indicator
light flashes and an alarm sounds intermittently.
The vehicle skid control activates when the vehicle speed is
about more than 15 km/h (9 mph).You may hear a sound in the engine compartment for a few
seconds when the engine is started or just after the vehicle is
started. This means that the vehicle skid control is in the
self±check mode and does not indicate a malfunction.
When
you turn the ignition switch on, this system always turns
on.

STARTING AND DRIVING
245
Vehicle skid control system failure warning
SV31035
These lights warn that there is a problem somewhere in the
vehicle skid control system or traction control system.
The lights will come on when the ignition key is turned to ºONº,
and will go off after a few seconds.
If the ºVSCº warning light and ºTRAC OFFº indicator/warning
light come on, the vehicle skid control system and traction
control system do not work. However, as conventional braking
operates when applied, there is no problem to continue your
driving.
If any of the following conditions occurs, this indicates a
malfunction somewhere in the parts monitored by the warning
light system. Contact your Lexus dealer as soon as possible
to service the vehicle:
 The ºVSCº warning light or ºTRAC OFFº indicator/warning
light do not come on after the ignition is turned to on.
 The ºVSCº warning light and ºTRAC OFFº indicator/warning
light remain on after the ignition is turned to on. 
The ºVSCº warning light and ºTRAC OFFº indicator/warning
light come on while driving without pushing ºTRAC OFFº
switch.
CAUTION
Do not rely excessively on the vehicle skid control
system. Even if the vehicle skid control system is
operating, you must always drive carefully and atten-
tively to avoid serious injury. Reckless driving will
result in an unexpected accident. If the slip indicator
light flashes, sounding an alarm, special care should
be taken while driving.
 Only use tires of specified size. The size, manufac-
turer, brand and tread pattern for all 4 tires should be
the same. If you use the tires other than specified, or
different type or size, the vehicle skid control system
may not function correctly. When replacing the tires
or wheels, contact your Lexus dealer.

STARTING AND DRIVING
246
ELECTRONIC THROTTLECONTROL SYSTEM
The electronic throttle control system always maintains
appropriate engine output in relation to the accelerator
opening in all driving conditions.
SV31038
You can select the snow mode by pushing the ºSNOWº
switch. The ºSNOWº indicator light will come on.
Snow mode: Decreases the engine output to minimize rear
wheel spinning on snowcovered or slippery roads.
To return to the normal mode, push the ºSNOWº switch again.
The ºSNOWº indicator light will go off.
When you turn the ignition switch off in the snow mode, the
mode automatically changes to the normal mode.
BRAKE SYSTEM
The tandem master cylinder brake system is a hydraulic
system with two separate sub±systems. If either sub±system
should fail, the other will still work. However, the pedal will be
harder to press, and your stopping distance will be longer.
Also, the brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a single brake
system. Have your brakes fixed immediately.
Brake booster
The brake booster uses engine vacuum to power±assist the
brakes. If the engine should quit while you are driving, you can
bring the vehicle to a stop with normal pedal pressure. There
is enough reserved vacuum for one or two stops but no more!
CAUTION
Do not pump the brake pedal if the engine stalls.
Each push on the pedal uses up your reserved
vacuum.
 Even if the power assist is completely lost, the brakes
will still work. But you will have to push the pedal
hard, much harder than normal. And your braking
distance will be longer.

ENGINE
308
FUEL PUMP SHUT OFF SYSTEM
The fuel pump shut off system stops supplying fuel to the
engine to minimize the risk of fuel leakage when the engine
stalls or an airbag inflates upon collision. To restart the engine
after the fuel pump shut off system activates, turn the ignition
switch to ºACCº or ºLOCKº once and start it.
CAUTION
Inspect the ground under the vehicle before restarting
the engine. If you find that liquid has leaked onto the
ground, it is the fuel system has been damaged and it is
in need of repair. In this case, do not restart the engine.
FACTS ABOUT ENGINE OILCONSUMPTION
Functions of engine oil
Engine oil has the primary function of lubricating and cooling
the inside of the engine, and plays a major role in maintaining
the engine in proper working order.
Engine oil consumption
It is normal that an engine should consume some engine
oil during normal engine operation. The causes of oil
consumption in a normal engine are as follows.
Oil is used to lubricate pistons, piston rings and cylinders.
A thin film of oil is left on the cylinder wall when a piston
moves downwards in the cylinder. High negative pressure
generated when the vehicle is decelerating sucks some of
this oil into the combustion chamber. This oil as well as
some part of the oil film left on the cylinder wall is burned by
the high temperature combustion gases during the
combustion process.
 Oil is also used to lubricate the stems of the intake valves.
Some of this oil is sucked into the combustion chamber
together with the intake air and is burned along with the fuel.
High temperature exhaust gases also burn the oil used to
lubricate the exhaust valve stems.

CHASSIS
321
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.

ELECTRICAL COMPONENTS
336
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

ELECTRICAL COMPONENTS
337
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

ELECTRICAL COMPONENTS
341
CHECKING AND REPLACING THEBLADE TYPE FUSES
SS64009

Driver's side kick panel
SS64012a

Passenger's side kick panel
SV64017

Engine compartment 1Spare fuses 2Pull±out tool
1. Turn the ignition switch off and open the fuse box lid.
Determine which fuse may be causing the problem. The lid of
the fuse box shows the name of the circuit for each fuse.