How To Read Wiring Diagrams: Wiring Diagram

The wiring diagram of each system is illustrated so that you can understand path through which electric current flows from battery.

Sketches and codes are used in the diagrams.

They should read as follows:

• Each connector and its terminal position are indicated by a sketch of the connector in a disconnected state which is viewed from front.
  Fig 1: View Of Connector And Terminal Position

  Courtesy of SUBARU OF AMERICA, INC.
• The number of poles or pins, presence of a lock, and pin number of each terminal are indicated in sketch of each connector. In sketch, the highest pole number refers to number of poles which connector has. For example, the sketch of the connector shown in figure indicates connector has 9 poles.

  Connector used in vehicle	Connector shown in wiring diagram
  	Sketch	Symbol	Number of poles
  			Numbered in order from upper right to lower left.
  			Numbered in order from upper left to lower right

• When one set of connectors is viewed from the front side, the pole numbers of one connector are symmetrical to those of the other. When these two connectors are connected as a unit, the poles which have the same number are joined.
  Fig 2: Pole Numbers Of Connector Symmetrical With Each Other

  Courtesy of SUBARU OF AMERICA, INC.
• Electrical wiring harness:

  The connectors are numbered along with the number of poles, external colors, and mating connections in the accompanying list.

• The sketch of each connector in the wiring diagram usually shows the (A) side of the connector. The relationship between the wire color, terminal number and connector is described in figure.
  NOTE: A wire which runs in one direction from a connector terminal sometimes may have a different color from that which runs in the other direction from that terminal.
  Fig 3: Sketch Of Connector In Wiring Diagram

  Courtesy of SUBARU OF AMERICA, INC.
• In wiring diagram, connectors which have no terminal number refer to one-pole types. Sketches of these connectors are omitted intentionally.
  Fig 4: Connectors Wiring Diagram (No Terminal Number Refer To One-Pole Types)

  Courtesy of SUBARU OF AMERICA, INC.
• The following color codes are used to indicate the colors of the wires used.

  Color code	Color
  L	Blue
  B	Black
  Y	Yellow
  G	Green
  R	Red
  W	White
  Br	Brown
  Lg	Light green
  Gr	Gray
  P	Pink
  Or	Orange
  Lb	Light Blue
  V	Violet
  SA	Sealed (Inner)
  SB	Sealed (Outer)

  Fig 5: Connector Wire Color Codes

  Courtesy of SUBARU OF AMERICA, INC.
• The wire color code, which consists of two letters (or three letters including Br or Lg), indicates the standard color (base color of the wire covering) by its first letter and the stripe marking by its second letter.
  Fig 6: Connector Wire Color Codes (Base Color Of Wire Covering)

  Courtesy of SUBARU OF AMERICA, INC.
• The table lists the nominal sectional areas and allowable currents of the wires.
  CAUTION: When replacing or repairing a wire, be sure to use the same size and type of the wire which was originally used.
  NOTE:

  • The allowable current in the table indicates the tolerable amperage of each wire at an ambient temperature of 40°C (104°F).
  • The allowable current changes with ambient temperature. Also, it changes if a bundle of more than two wires is used.

  Nominal sectional area	No. of strands/strand diameter	Outside diameter of finished wiring mm	Allowable current Amps/40°C (104°F)
  mm2		mm
  0.3	7/0.26	1.8	7
  0.5	7/0.32	2.2 (or 2.0)	12
  0.75	30/0.18	2.6 (or 2.4)	16
  0.85	11/0.32	2.4 (or 2.2)	16
  1.25	16/0.32	2.7 (or 2.5)	21
  2	26/0.32	3.1 (or 2.9)	28
  3	41/0.32	3.8 (or 3.6)	38
  5	65/0.32	4.6 (or 4.4)	51
  8	50/0.45	5.5	67

• Each unit is directly grounded to the body or indirectly grounds through a harness ground terminal. Different symbols are used in the wiring diagram to identify the two grounding systems.
  Fig 7: Direct Ground And Indirect Harness Ground Terminal

  Courtesy of SUBARU OF AMERICA, INC.
• The ground points shown in the wiring diagram refer to the following:
  NOTE: All wiring harnesses are provided with a ground point which should be securely connected.
  Fig 8: Ground Points

  Courtesy of SUBARU OF AMERICA, INC.
• Relays are classified as normally-open or normally-closed. The normally-closed relay has one or more contacts.

  The wiring diagram shows the relay mode when the energizing circuit is OFF.

  Fig 9: Relay Mode Wiring Diagram

  Courtesy of SUBARU OF AMERICA, INC.
• Each connector number shown in the wiring diagram corresponds to that in the wiring harness. The location of each connector in the actual vehicle is determined by reading the first character of the connector (for example, a "F" for F8, "i" for i16, etc.) and the type of wiring harness.

  The first character of each connector number refers to the area or system of the vehicle.

  Symbol	Wiring harness and cord
  F	Front wiring harness
  B	Bulkhead wiring harness
  E	Engine wiring harness
  T	Transmission cord, Rear oxygen sensor cord
  D	Door cord LH & RH, Rear door cord LH & RH, Rear gate cord
  i	Instrument panel wiring harness
  R	Rear wiring harness, Fuel tank cord, Roof cord, On refueling vapor recovery cord

  Fig 10: Wiring Harness And Cord Location

  Courtesy of SUBARU OF AMERICA, INC.