Marine Wire Color Codes

Marine Wire Color Code

The ABYC (American Boat and Yacht Council) has the following suggested marine wiring color codes:

FOR General Purpose DC Wiring:
DC Positive - RED
DC Negative - BLACK or YELLOW

FOR General Purpose AC Wiring:
Ungrounded Conductor (HOT) - BLACK or BLACK w BLUE, RED, ORANGE STRIPE(S)
Additional Ungrounded Conductors (HOT) - RED, ORANGE, BLUE
Grounded Neutral Conductor (NEUTRAL) - WHITE or LIGHT BLUE
Grounding Conductor (GROUND) - GREEN or GREEN w YELLOW STRIPE(S)

Starting Circuit (starting switch to solenoind) - YELLOW with Red Stripe
Bilge Blowers (fuse or switch to blower) - BROWN with Yellow Stripe or YELLOW
Navigation Lights (fuse or switch to lights) - DARK GRAY
Tachometer (Tachometer sender to gauge) - DARK GRAY
Generator Armature (armature to regulator) - BROWN
Alternator Charge Light (generator terminal/alternator aux terminal to light to regulator) - BROWN
Pumps - (fuse or switch to pumps) BROWN
Accessory Feed (ammeter to alternator or generator output and accessory fuses or switches) - ORANGE
Ignition (ignition switch to coil and electrical instruments) - VIOLET
Instrument Feed (distribution panel to electric instruments) - VIOLET
Cabin and Instrument Lights (fuse or switch to lights) - DARK BLUE
Oil Pressure (Oil pressure sender to gauge) - LIGHT BLUE
Water Temperature (water temp sender to gauge) - TAN
Fuel Gauge (fuel gauge sender to gauge) - PINK
Tilt Down and or Trim In (tilt and/or trim circuits) - GREEN w Stripe (except yellow stripe)
Tilt Up and/or Trim Out (tit and/or trim circuits) - BLUE w Stripe

Further Explanation of the ABYC Marine Color Code:

Each electrical conductor that is part of the boat's electrical system shall have a means to identify its function in the system. EXCEPTION: Pigtails less than seven inches (175mm) in length.
Basically ABYC wants you to have a way to identify your boat's wiring system. Manufacturers should have provided a wiring diagram and means of identification with the boat. 

The color code shown above from the ABYC identifies one selection of colors for use as an engine accessory wiring color code. Other means of identification may be used providing a wiring diagram
of the system indicating the method of identification is provided with each boat.
This simply states that the colors above are not the ONLY color code that can be used. Other identification can be used, the important part is that wires are clearly identified

Color-coding may be accomplished by colored sleeving or color application to wiring at termination points. If tape is used to mark a wire, the tape shall be at least 3/16 inch (5mm) in width, and shall have sufficient length to make at least two complete turns around the conductor to be marked. The tape shall be applied to be visible near each terminal.
So don't fret if you can't find a color of wire or it's not feasible to replace a certain colored wire run as you can attach tape or heat shrink which is colored to the ends of the wire near the termination point