Operation CHARM: Car repair manuals for everyone.

How to Read and Use Wiring Diagrams

SYMBOLS USED IN THE WIRING DIAGRAMS

Symbols: Fuses:




Fuses
In the wiring diagrams, every subsystem is generally shown from the relevant fuse in the main fuse box up to the respective component or components and on to the grounding point or direct chassis connection.

The current supplied to each fuse is shown separately in the positive supply system group, which also covers the car's main fuse box, ignition switch, etc.

Example:
If the current supplied to a fuse comes from the +30 terminal, the circuit incorporating the fuse in question will be found in the "Power supply (+30 circuit)".

Symbols: Grounding Points:




Grounding points
Most of the car's grounding points have a component number consisting of a letter and a number, e.g. G2 or G29. The locations of the grounding points on the car are given in the "Grounding Points".

Switches, Relays And Components
Unless otherwise indicated, switches and relays are drawn in the unenergized and inactivated state.

When the box round the component is drawn with an unbroken line, the whole component is shown.

When the box round the component is drawn with a broken line, only part of the component is shown.

On some components having a hanging lead, the connector has not been given a separate H number to show that it is part of the component.

The components are designated by a serial number and one or more letter suffixes which indicate location or variant. Locations are indicated by upper-case (capital) letters, e.g. 298FL, while variants are indicated by a lower-case (small) letter, e.g. 47a. The following abbreviations for the various locations are used:

C = Centre
D = Driver (driver's side)
F = Front
H = Hatch (tailgate)
P = Passenger (front-seat passenger's side)
R = Rear
LH = Left Hand (left-hand side)
RH = Right Hand (right-hand side)

Symbols: Crimp Connections:




Crimp Connections
To reduce the number of connectors used in the car, several crimp connections are incorporated in the wiring. They occur as fixed wiring connections and also as connectors. The number of contacts in the connector may vary, depending on the market and car variant. The maximum variant is always shown on the schematic. There is no pin numbering on the connectors.

The symbol used for these in wiring diagrams is shown in the above image.