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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.
^ Connector symbols shown from the harness side are enclosed by a double line and followed by the direction mark.





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


WIRING DIAGRAMS - EXAMPLE

Wiring Diagram - Example:




Sample/Wiring Diagram Optional Splice:






WIRING DIAGRAM LEGEND

How To Read Wiring Diagrams - Description:




How To Read Wiring Diagrams - Description (Part 2 Of 2):






DETECTABLE AND NON-DETECTABLE LINES

Detectable Lines And Non-detectable Lines:





In some wiring diagrams, two kinds of lines, representing wires with different thicknesses are used to represent wires.
^ 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 ECCS control module (ECM) can detect malfunctions with the on-board diagnostic system.
^ A line with less thickness (thinner line) represents a "non- detectable line for DTC". A "non-detectable line for DTC" is a circuit in which ECM cannot detect malfunctions with the on-board diagnostic system.


SWITCH POSITIONS

Switch Positions:




Wiring diagram switches are shown with the vehicle in the following condition.
Ignition switch "OFF".
Doors, hood and trunk lid/back door closed.
Pedals are not depressed and parking brake is released.


MULTIPLE SWITCH

Multiple Switch:




The continuity of the multiple switch is identified in the switch chart in wiring diagrams.


SUPER MULTIPLE JUNCTION (SMJ)


Super Multiple Junction (SMJ):




^ The "SMJ" indicated in wiring diagrams is shown in a simplified form.
^ The foldout should be spread to read the entire wiring diagram.