Toyota LEXUS IS 300 2003 User Manual

FOREWORD
This wiring diagram manual has been prepared to provide
information on the electrical system of the 2004 IS 300.
Applicable models: JCE10 Series
For service specifications and repair procedures of the above
models other than those listed in this manual, refer to the
following manuals;
Manual Name
• 2003 LEXUS IS 300 Repair Manual
Volume 1
Volume 2
• 2003 LEXUS New Car Features
Pub. No.
RM1054U1
RM1054U2
NCF259U
All information in this manual is based on the latest product
information at the time of publication. However, specifications
and procedures are subject to change without notice.
TOYOTA MOTOR CORPORATION
NOTICE
When handling supplemental restraint system components (removal,
installation or inspection, etc.), always follow the direction given in the repair
manuals listed above to prevent accidents and supplemental restraint
system malfunction.

Toyota LEXUS IS 300 2003 Specifications

General

Brand	Toyota
Model	LEXUS IS 300 2003
Category	Automobile
Language	English

Summary

FOREWORD

INTRODUCTION

HOW TO USE THIS MANUAL

WIRING COLOR AND CONNECTOR CODES

Explains the meaning of color codes and connector notations used in diagrams.

SYMBOL EXPLANATIONS

Glossary of technical terms and common electrical schematic symbols.

GROUND POINT CIRCUIT DIAGRAM

Shows connections from major parts to vehicle ground points.

POWER SOURCE (Current Flow Chart)

CONNECTOR LIST

PART NUMBER OF CONNECTORS

TROUBLESHOOTING

VOLTAGE CHECK

Procedures for checking voltage levels in electrical circuits.

CONTINUITY AND RESISTANCE CHECK

Methods for testing circuit continuity and resistance.

FINDING A SHORT CIRCUIT

Techniques for locating short circuits within wiring.

CONNECTOR DISCONNECTION

Proper methods for disconnecting male and female electrical connectors.

TERMINAL REPLACEMENT

Step-by-step guide for replacing electrical terminals in connectors.

ABBREVIATIONS

GLOSSARY OF TERMS AND SYMBOLS

RELAY LOCATIONS

ENGINE COMPARTMENT AND INSTRUMENT PANEL RELAY LOCATIONS

Diagrams showing relay and fuse box placement in the engine and interior.

BODY RELAY LOCATIONS

Diagrams showing relay and fuse box placement in the vehicle body.

FUSE AND RELAY BOX DIAGRAMS

Detailed layouts of fuse and relay boxes in engine compartments.

JUNCTION BLOCK INNER CIRCUITS

Internal circuit diagrams for driver and passenger side junction blocks.

ELECTRICAL WIRING ROUTING

OVERALL ELECTRICAL WIRING DIAGRAM

RADIO AND PLAYER WIRING DIAGRAM

Circuit diagram for the audio system.

REAR WIPER AND WASHER WIRING DIAGRAM

Circuit diagram for the rear wiper and washer system.

TAILLIGHT WIRING DIAGRAM

Circuit diagram for the taillight system.

REAR LIGHTS WIRING DIAGRAM

Circuit diagram for various rear lighting components.