Nissan Altima 2007-2012 Service Manual: 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 PG section, “Description”, “HARNESS CONNECTOR”.

• Male and female terminals

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

Sample/wiring diagram -example-

• For detail, refer to following GI-11, "Description".



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.


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.

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