Harley Davidson Wiring Color Codes: Comprehensive Guide

Harley Davidson motorcycles are renowned for their style, performance, and attention to detail. One aspect that requires such attention is the wiring and electrical components of the motorcycle. This is where wiring color codes come into play, ensuring that the electrical system functions efficiently and is easy to troubleshoot when required.

Understanding Harley Davidson wiring color codes helps not only professional mechanics but also DIY enthusiasts working on their own bikes. These color codes serve as a guide to identify specific wires and facilitate repairs or customization efforts. Harley Davidson motorcycles employ a standardized set of color codes for various components, such as ignition coils, batteries, harnesses, brake light switches, and turn signal switches, among others.

By knowing the Harley Davidson wiring color codes, owners can save time by quickly finding specific wires or parts. This makes the motorcycles safer and helps them run more smoothly. Taking care of the electrical system on a Harley Davidson is easy if you are sure of yourself and know what you are doing.

Harley Davidson Wiring Color Codes

Harley Davidson motorcycles have specific wiring color codes to help owners and mechanics identify various components, ensuring a safe and efficient electrical system. Understanding these color codes is crucial for proper maintenance and customization.

In general, the color coding for wiring on the Electronic Control Module (ECM) is based on polarity. Orange wires signify positive connections and are connected to orange connectors, while black wires denote negative connections and go to black connectors.

Common color codes found in Harley Davidson motorcycles include:

  • Red: This color is often used for power wires and accessory circuits.
  • Black: As mentioned earlier, solid black wires serve as ground or negative connections.
  • White: White wires are typically used for low-beam headlight connections.
  • Blue: Solid blue color wires are commonly used for high-beam headlight connections.
  • Green: Solid green wires often indicate neutral or running light connections.
  • Yellow: Yellow wires may be used for various purposes, such as turn signal circuits.
  • Orange: Orange wires are generally used for positive connections on electronic components.
  • Violet, Grey, Pink, and Purple: These colors might be used for specialized circuits or components, and their specific meanings can vary based on the model and year of the motorcycle.

In some cases, Harley Davidson wiring includes wires with striped patterns. For instance, a yellow wire with a black stripe is often used for low-beam connections. Additionally, a green wire with a red or yellow stripe may be used for brake light circuits.

To ensure the correct identification of wires and their functions on your Harley Davidson, always refer to the wiring diagram or service manual specific to your motorcycle’s model and year. This will help guarantee a safe and efficient electrical system, both during regular maintenance and when adding custom components.

Installation and Components

Harley Davidson motorcycles have a unique and specific wiring color code system that assists in the installation and repair of their bikes. This system is designed for easy identification of wires, making troubleshooting, servicing, and repairs much easier for technicians and enthusiasts alike.

When installing new components or repairing existing ones, it’s essential to familiarize oneself with the Harley Davidson wiring color codes. These color codes represent various wires and their corresponding functions, ensuring a safe and accurate installation process. Some examples of these color codes are red for the ignition coil, white for the battery, and orange for the harness.

Knowing the location of these color-coded wires can be crucial when looking to service or repair specific components within the motorcycle. For instance, the brake light switch is represented by a purple wire, while the headlight switch is indicated by a black wire. Proper identification of these wires saves time and reduces the risk of potential issues during the installation process.

It’s worth noting that Harley Davidson also offers official service manuals for their motorcycles. These manuals provide in-depth information on wiring diagrams, circuit diagrams, and much more, making them a valuable resource for technicians and DIY enthusiasts working on their bikes. These manuals often contain specific color codes unique to each model, ensuring that all drivers have the correct information when working on their vehicle.

While some Harley Davidson models may require additional parts like an adapter wiring harness for installation, it’s essential to follow the repair manual instructions concerning wiring and components. Doing so guarantees a more efficient and precise installation process while minimizing potential issues.

Harley Davidson Wiring Diagram – Reference

Every Harley-Davidson motorcycle is unique, and understanding their wiring color codes is important for maintaining and customizing your bike. Thankfully, Harley-Davidson provides detailed wiring diagram information for motorcycle enthusiasts and professionals alike.

One can find suitable wiring diagrams on the Harley-Davidson Service Information Portal. These diagrams show complete systems or specific circuits, depending on the title of the diagram. When examining these diagrams, always refer to the title for the type of diagram being presented. This can significantly help when troubleshooting any wiring-related issues.

The wiring color codes are essential for identifying the specific circuits within the bike’s electrical system. Familiarity with these codes not only eases the process of working on the motorcycle, but also helps ensure that any modifications or repairs done are accurate and safe.

It is crucial to remember that each Harley-Davidson motorcycle’s wiring may vary slightly, and it is important to consult the appropriate diagrams and resources specific to your bike’s model and year. This care ensures that any work you do on your motorcycle is accurate and maintains the high-quality performance one expects from a Harley-Davidson.

By taking advantage of available resources and understanding the nuances of your motorcycle’s wiring and color codes, you can confidently keep your Harley-Davidson in peak condition and customize it to suit your unique preferences.

Wire Location Identification

When working on the electrical systems of a Harley Davidson, understanding the wiring color codes is crucial. In this section, we’ll look into identifying the wires related to tail lights, turn signals, and brake lights.

Identifying Tail Light Wires

The tail light wires on Harley Davidson motorcycles are typically blue. To ensure accuracy, it’s important to consult the wiring diagram specific to your motorcycle model and production year. This color coding makes it easier to identify tail light wires when working on lighting upgrades, maintenance, or repairs.

Identifying Turn Signal Wires

The turn signal wires on a Harley Davidson are usually violet for the left signal and brown for the right signal. Turn signal wires can also be gray/pink for the left and brown/yellow for the right, depending on the model source. It’s essential to verify these color codes in your motorcycle’s wiring diagram. Knowing the correct color codes for the turn signals ensures proper installation and functioning of the signals.

Identifying Brake Wires

Harley Davidson brake wires are commonly red with a yellow stripe. This color code makes it easy to locate and distinguish the brake wires from other wires in the system. Checking the wiring diagram specific to your model is always recommended to ensure the accuracy of color codes.

Safety Considerations

When working with Harley Davidson wiring color codes, it’s essential to prioritize safety for both the motorcycle and its rider. Understanding the color codes and following proper procedures ensure that the electrical connections are secure and correctly installed. Let’s discuss some important safety aspects while working with Harley Davidson wiring color codes.

First and foremost, always secure your bike. Place the motorcycle on a stable, flat surface, and turn off the ignition. Disconnect the battery to prevent any accidental short circuits or shocks. This will ensure that the motorcycle remains stable and safe while working with the wiring.

Grounding is a vital aspect when dealing with electrical wiring. Ensure that all connections, especially those that involve the motorcycle’s frame, are appropriately grounded. This will help protect the electrical components from damage and prevent any unintended electrical shorts or fires. Proper grounding not only ensures safety but also maintains the optimal functioning of the motorcycle’s electrical system.

Wiring colors play an important role in the electrical system’s safety. Knowing the standard Harley Davidson wire color codes can assist you in diagnosing, troubleshooting, and fixing wiring faults. Understanding the color codes will help you avoid confusion and wiring mistakes, which can lead to accidents or malfunctions.

Additionally, it’s crucial to use the right tools and materials while working on the wiring. Examine all the wire connections and use the appropriate tools to perform modifications or repairs. For instance, use high-quality connectors, cable ties, and heat shrink tubing to ensure all connections are secure and properly insulated.


Harley Davidson wiring color codes are essential for the proper functioning of the electrical systems in these motorcycles. When experiencing issues with the wiring, it’s crucial to troubleshoot the problem to ensure a smooth and safe ride.

Firstly, inspect the wiring for any signs of corrosion, broken wires, and poor continuity. Damaged wiring can cause electrical problems, and it’s vital to address these issues to prevent further complications. Regular maintenance can help prevent wiring issues and save time and money in the long run.

When analyzing the electrical system, draw a diagram to map out the wires and connections. Using a diagram can simplify the process and help identify any potential faults. Additionally, note any discrepancies and use the color codes to determine wire functions. A ground wire, for example, is crucial for completing electrical circuits and ensuring proper grounding.

If a new thread is needed, use 16-gauge or 18-gauge insulated copper wire for the best results. These wire gauges are commonly used for Harley Davidson wiring systems and provide optimal electrical performance.


What is the significance of wiring color codes in Harley Davidson motorcycles?

Harley Davidson wiring color codes are essential to identify individual wires that are responsible for different functions in the bike’s electrical system. This system standardizes the wiring, making repairs, modifications, and troubleshooting more efficient.

Can I use third-party replacement wires or should I use Harley Davidson branded parts?

While third-party wires can sometimes be used, it’s advisable to use wires that meet or exceed the specifications provided by Harley Davidson for your particular model. Using incompatible parts may lead to problems down the road.

What tools will I need to work on my Harley’s wiring?

Working on the wiring typically requires tools like wire strippers, crimpers, a multimeter, screwdrivers, and sometimes soldering equipment. Always make sure to disconnect the battery before working on the electrical system.

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