How to Read Wiring Diagrams

How to Read Wiring Diagrams

CONNECTOR SYMBOLS
Most of connector symbols in wiring diagrams are shown from the terminal side.




- Connector symbols shown from the terminal side are enclosed by a single line and followed by the direction mark.
- Connector symbols shown from the harness side are enclosed by a double line and followed by the direction mark.
- Certain systems and components, especially those related to OBD, may use a new style slide-locking type harness connector. For description and how to disconnect, refer to "HARNESS CONNECTOR".




- Male and female terminals

Connector guides for male terminals are shown in black and female terminals in white in wiring diagrams.










WIRING DIAGRAMS - EXAMPLE

Description (Item: 1 - 19):

Description (Item: 20 - 32):

WIRING DIAGRAM DESCRIPTIONS





SWITCH POSITIONS
Switches are shown in wiring diagrams as if the vehicle is in the "normal" condition.

A vehicle is in the "normal" condition when:
- ignition switch is "OFF",
- doors, hood and trunk lid/back door are closed,
- pedals are not depressed, and
- parking brake is released.




DETECTABLE LINES AND NON-DETECTABLE LINES
In some wiring diagrams, two kinds of lines, representing wires, with different weight are used.
- A line with regular weight (wider line) represents a "detectable line for DTC (Diagnostic Trouble Code)". A "detectable line for DTC" is a circuit in which ECM can detect its malfunctions with the on board diagnostic system.
- A line with less weight (thinner line) represents a "non-detectable line for DTC". A "non-detectable line for DTC" is a circuit in which ECM cannot detect its malfunctions with the on board diagnostic system.




MULTIPLE SWITCH
The continuity of multiple switch is described in two ways as shown below.
- The switch chart is used in schematic diagrams.
- The switch diagram is used in wiring diagrams.