How to Read and Use Wiring Diagrams

SYMBOLS USED IN THE WIRING DIAGRAMS

Symbols - Fuse:

Fuses
In the wiring diagrams, every sub-system is generally shown from the relevant fuse in the main fuse box up to the component or components concerned and then to the grounding point or chassis connection.

Symbols - Power Supply:

The power supply to each fuse is shown separately in the positive supply (P) sub-system, where the car's fuse box, ignition switch, etc. are covered.

An example:
When the power supply to a fuse comes from the +30 terminal, the supply up to the fuse concerned can be seen under Starting and Charging/Power and Ground Distribution/Electrical Diagrams/Power supply, +30.

Symbols - Grounding Points:

Grounding points
Most of the grounding points in the car have a component number consisting of a letter and a number, e.g. G2 or G29. The locations of the grounding points are described under Diagram Information and Instructions/Ground Information.

Symbols - Switches And Relays:

Switches, relays and components
Unless otherwise specified, switches are shown in the non-actuated state and relays in the de-energized state.

Symbols - Components:

When the component box is drawn with unbroken lines, the whole component is shown.

Symbols - Components:

When the component box is drawn with broken lines, part of the component is shown.

Symbols - Crimped Connections:

Crimped connections
To reduce the number of connectors, a number of connections are crimped. The symbol for a crimped connection in the wiring diagram is shown in the above image.