Views: 222 Author: Ann Publish Time: 2025-04-18 Origin: Site
Content Menu
● Understanding the Turn Signal Relay on a Harley
>> Why the Turn Signal Relay Matters
● Where Is the Turn Signal Relay Located on a Harley?
● Step-by-Step Guide to Locate and Access the Turn Signal Relay
● Troubleshooting Harley Turn Signal Indicator Not Working
>> Testing the Turn Signal Relay
● Fixing the Harley Turn Signal Indicator Not Working
>> Replacing the Turn Signal Module
>> Upgrading to LED-Compatible Modules
>> Wiring Tips
● FAQ
>> 1. Where exactly is the turn signal relay located on a 2008 Harley Street Bob?
>> 2. What should I do if my Harley turn signal indicator is blinking rapidly?
>> 3. How can I test if the turn signal module is faulty?
>> 4. Can I replace the turn signal relay myself?
>> 5. Why do my Harley turn signals light up but not flash?
When dealing with the issue of a Harley turn signal indicator not working, one of the first components to inspect is the turn signal relay, also known as the flasher relay or turn signal module. This article provides a comprehensive guide on locating the turn signal relay on various Harley-Davidson models, troubleshooting common problems, and offers practical solutions including wiring tips and replacement advice. Along the way, you will find detailed explanations and step-by-step instructions to assist you in diagnosing and fixing your Harley's turn signal issues.
The turn signal relay is an electrical component responsible for making your turn signals blink on and off. Unlike traditional motorcycles that use a simple flasher relay, many Harley-Davidson models use a more complex turn signal module or flasher module, which controls the blinking pattern electronically.
If your Harley turn signal indicator is not working, the problem often lies with the relay/module. Symptoms include:
- Turn signals lighting up but not blinking (solid light)
- Turn signals not lighting at all
- Rapid blinking or irregular flash patterns
- Turn signals working intermittently or stopping after riding a short distance
The turn signal relay is essential for safe riding as it communicates your intentions to other drivers. A malfunctioning relay can lead to confusion and potential accidents, making timely diagnosis and repair critical.
The location of the turn signal relay/module varies by Harley model and year, but the most common places to find it include:
- Near the fuse panel: Many Harley models house the turn signal module close to the fuse box under the seat or near the battery compartment.
- Under the seat: Some models, especially Sportsters and Touring bikes, have the relay mounted under the seat or inside a triangular cover on the left side of the bike.
- On or near the rear fender: In some cases, the relay might be mounted on the rear fender or under the rear seat area.
- Inside the left side triangle cover: For example, on a 1999 Sportster 883 Hugger, the turn signal module is located under the left side triangle-shaped cover.
The turn signal module often looks like a small black box or module with multiple wiring connectors. It may have a plastic resin or epoxy coating on the back for protection. It is different from the older-style mechanical flasher relays and can sometimes get hot during operation.
- Sportster Models: On many Sportsters, the turn signal module is located under the left side triangular cover. Removing this cover reveals the module mounted on or near the frame.
- Touring Models: For Touring Harleys such as the Electra Glide or Road King, the relay is often found near the battery compartment or under the seat, sometimes integrated into the fuse box assembly.
- Dyna Models: Dyna motorcycles typically have the relay under the seat or near the rear fender, often secured with clips or screws.
Knowing your specific model and year can greatly simplify locating the turn signal relay.
1. Remove the seat: Most Harley models require removing the seat to access the electrical components underneath. This usually involves loosening bolts or screws with the appropriate tools.
2. Locate the fuse panel or battery compartment: Look for the fuse box or battery area; the relay is often nearby. The fuse panel is typically a black plastic box with several fuses and relays inside.
3. Look for a small black box or module: The turn signal module will have wiring harnesses plugged into it. It may be mounted on the frame or attached to the fuse panel.
4. Check under the left side triangle cover: On some models, this triangular cover hides the relay. Carefully remove the cover by loosening screws or clips.
5. Consult your model's service manual: For exact location and wiring diagrams, the service manual is invaluable. It provides detailed illustrations and step-by-step instructions specific to your Harley model.
- Faulty turn signal module/relay: The module can fail due to heat or electrical faults. Over time, internal components degrade, causing intermittent or complete failure.
- Burned out bulbs or LED incompatibility: LEDs often cause the relay to malfunction unless replaced with a compatible module. LED bulbs draw less current, which can confuse traditional flasher relays.
- Wiring issues or bad grounds: Loose connections or grounding problems can cause the turn signals to stop working. Corrosion or damaged wires are common culprits.
- Short circuits: Shorts between wires and ground can cause erratic behavior or complete failure of the turn signals.
- Swap the turn signal trigger wires: Swap the left and right turn signal wires at the relay to see if the problem follows the relay or stays with the wiring. If the problem moves, the relay is likely faulty.
- Use a test light or multimeter: Check for power and ground at the relay connectors. A lack of power or ground indicates wiring issues.
- Check bulb condition: Inspect bulbs for damage or burnout. Replace any faulty bulbs.
- Observe the blinking pattern: Rapid blinking usually indicates a bulb out or LED incompatibility.
If the module is faulty, replacing it is usually straightforward:
- Remove the seat and locate the module.
- Disconnect the wiring harness.
- Replace with a new OEM or compatible module.
- Reconnect wiring and test the signals.
It is important to use a module compatible with your Harley model and the type of bulbs installed (incandescent or LED).
When upgrading to LED turn signals, the stock flasher relay may not work properly, causing solid lights or rapid blinking. Installing an LED-compatible flasher relay or module designed for Harley-Davidson bikes solves this issue. These modules are designed to handle the lower current draw of LEDs and provide the correct flash rate.
- Ensure all bulbs and wiring grounds are secure and free of corrosion.
- Use wiring diagrams to correctly identify left and right signal wires.
- Avoid connecting both turn signals simultaneously unless using the hazard switch.
- Check connectors for corrosion or loose pins and clean or repair as needed.
- If installing aftermarket turn signals, verify polarity and compatibility with your relay/module.
- Some newer Harley models use a Body Control Module (BCM) that controls the turn signals electronically. In these cases, the turn signal relay may be integrated into the BCM, requiring diagnostic tools to troubleshoot.
- If your bike has a hazard light function, ensure that the hazard switch and wiring are functioning correctly, as faults here can affect turn signal operation.
- Always disconnect the battery before working on electrical components to avoid shorts or damage.
The turn signal relay (or module) on a Harley-Davidson motorcycle is typically located near the fuse panel, under the seat, or inside the left side triangle cover depending on the model. If your Harley turn signal indicator is not working, the relay is often the culprit, especially if you have upgraded to LED signals or experienced intermittent flashing issues. Proper diagnosis involves checking bulbs, wiring, grounds, and the relay itself. Replacement or upgrading to an LED-compatible module usually resolves most problems. Using the right tools, wiring diagrams, and following detailed guides can make the repair process much easier and restore your Harley's turn signals to full functionality, ensuring safe and legal riding.
The turn signal relay on a 2008 Street Bob is typically located near the fuse panel under the seat area. It is a module rather than a traditional flasher relay.
Rapid blinking usually indicates a bulb out or LED incompatibility. You may need to replace the bulb or install an LED-compatible flasher relay/module and perform a BCM Turn Signal Sync if your bike uses CanBUS electronics.
You can swap the left and right turn signal trigger wires to see if the problem follows the module. Also, use a test light or multimeter to check for power and ground at the relay connectors.
Yes, replacing the turn signal relay is generally straightforward. Remove the seat, locate the module, disconnect the wiring harness, and replace it with a new one. Always consult your model's service manual for specifics.
This is a common symptom of a faulty turn signal module or incorrect relay for LED bulbs. Replacing the module or installing an LED-compatible relay usually fixes this issue.
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[2] https://www.reddit.com/r/Fixxit/comments/16k88zd/2010_harley_davidson_sportster_forty_eight_turn/
[3] https://www.youtube.com/watch?v=BHOuISJDgtE
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[5] https://www.youtube.com/watch?v=HGshcgmNqz4
[6] https://www.fixmyhog.com/post/turn-signal-not-working
[7] https://www.youtube.com/watch?v=QUnP_Fg3yjs
[8] https://support.customdynamics.com/hc/en-us/articles/360051783233--CanBUS-Harley-Davidson-Rapid-Turn-Signal-Indicator-Flash
[9] https://www.hdforums.com/forum/electrical-lighting-alarm/1190399-turn-signals-right-side-not-working-only-riding-light-is-on.html
[10] https://www.youtube.com/watch?v=dLi3hEk15HI
