Standard Boat Wiring Color Codes
These are the most common color codes used in boat wiring. If you are looking for a new wiring harness setup check out the options on our Wiring Harnesses Page
| Black | Grounds, General |
| Black/Brown | Pump Grounds |
| Black/Red | Voltmeter Grounds |
| Black/Orange | Isolated Accessory Grounds |
| Black/Yellow | Ignition stop |
| Black/Green | Water Level Sender Ground |
| Black/Blue | Lighting Grounds |
| Black/Gray | Nav Light Grounds |
| Black/White | Battery Parallel Solenoid |
| Brown | Pumps, General, Bilge or Sump (Manually Switched)(Also alternator starter to Ign.) |
| Brown/Red | Pumps, Bilge or Sump |
| Brown/Orange | Power feed to Auto Bilge Switches, Pumps, Fuel/Oil Tranfer or Priming |
| Brown/Yellow | Baitwell or Aerator |
| Brown/Green | Fresh Water Pump/Water Maker |
| Brown/Blue | Head Pump |
| Brown/Violet | Washdown Pump |
| Brown/White | Trim pos sender |
| Red | Battery Feeds Unprotected |
| Red/Violet | Misc. Accy. Main Feed Protected (fused) from batt to trim panel. |
| Pink | Fuel Sender |
| Orange/Black | Audio System Feed |
| Orange/Brown | Electric Head, Sanitation System |
| Orange/Red | Wiper Port |
| Orange | Accessories common feed, Dist Panel to Acc switch, Anode Electrode, Mercathode |
| Orange/Yellow | Diesel Preheat |
| Orange/Green | Wiper Stbd |
| Orange/Blue | Communications Equipment |
| Orange/Violet | Navigation Equipment |
| Orange/White | Wiper Center |
| Yellow/Black | Choke Neutral saftey trans mounted |
| Yellow/Red | Start Solenoid (starting circut), Neutral Safety |
| Yellow/Orange | Powered Ventilation, Fans |
| Yellow | Bilge Blowers (also alternator DC output) |
| Yellow/White | Rudder Angle Sender |
| Green/Red | Stop Solenoid/Kill Switch |
| Green/Yellow | AC Grounding |
| Green | Bonding |
| Green/White | Engine Trim in and or tilt down |
| Green/Orange | Engine Independent Trim down |
| Blue/Black | Cabin Lights |
| Blue/Brown | Oil Temp Send |
| Blue/Red | Cabin or Cockpit Lights Port |
| Blue/Orange | Engine Independent Tilt Up |
| Blue/Yellow | Lighting Circuits to Remote Send |
| Blue/Green | Cabin or Cockpit Lights Stbd |
| Blue | Instrument & General Lighting |
| Blue/Violet | Courtesy, Boarding Lighting |
| Blue/White | Engine Trim Outand/or Tilt Up |
| Light Blue | Oil Pressure |
| Violet/Red | Eng. or Generator B+ from Breaker |
| Violet/Yellow | I/O Trim Up (ballast bypass) |
| Violet/Green | I/O Trim Down |
| Violet | 12v Ignition Generator or Engine |
| Violet/White | Trim "Trailer" switch |
| Gray/Black | Mast Light |
| Gray/Red | Spotlight Remote |
| Gray/Orange | Docking Lights |
| Gray/Green | Strobe or Beacon |
| Gray/Blue | Spreader/Flood Lights |
| Gray/Violet | Windlass/Winch |
| Gray | Navigation (running) Lights, Tach. Send |
| Gray/White | Anchor Light |
| White/Brown | Temp. Alarm or Indicator |
| White/Red | Fuel Alarm or Indicator ((Ignition module to Dist.)Mercury Thunderbolt Ignition) |
| White/Orange | Fire Alarm or Indicator |
| White/Yellow | Air Flow Alarm or Indicator |
| White/Green | Water Press/Flow Alarm or Indicator ((Ignition module to Dist.)Mercury Thunderbolt Ignition) |
| White/Blue | Oil Press Alarm or Indicator |
| White/Violet | Voltage Alarm or Indicator |
| White | General Alarm Usage, Yamaha Kill Switch |
| Tan | Water Temp sender |
| Tan/Blue | Warning system sense wire (Audio warning) |
