This guide walks you through how to reset Harley engine light on various models using simple tools and procedures. Whether you’ve fixed the issue or just need to clear the warning, we’ll help you do it safely and correctly.
Key Takeaways
- Understand why the engine light comes on: The check engine light (also called the malfunction indicator lamp or MIL) signals a problem detected by your Harley’s onboard diagnostics system, ranging from minor sensor issues to serious engine faults.
- Diagnose before resetting: Never reset the light without identifying and fixing the root cause—doing so may mask a serious issue and lead to costly repairs or unsafe riding conditions.
- Use an OBD2 scanner for most models: Modern Harley-Davidson motorcycles (2008 and newer) use OBD2 systems, making a scanner the most reliable way to read codes and reset the engine light.
- Older models may allow manual resets: Some pre-2008 Harleys (like certain Sportsters or Dynas) can have the light cleared using the ignition key and throttle, but this method is less reliable and not supported on all bikes.
- Resetting doesn’t fix the problem: Clearing the code only turns off the light—if the underlying issue remains, the light will likely return within a few rides.
- Keep a record of error codes: Write down any diagnostic trouble codes (DTCs) before resetting so you can track recurring problems or share them with a mechanic.
- When to see a professional: If the light returns quickly, flashes, or is accompanied by performance issues, consult a certified Harley technician immediately.
How to Reset Harley Engine Light: A Complete Step-by-Step Guide
So, you’re riding your Harley, feeling the wind in your face, when suddenly—*bam*—the engine light pops on. Your heart skips a beat. Is it serious? Can you fix it yourself? And most importantly: how do you reset the Harley engine light?
Don’t panic. While the check engine light can be alarming, it’s often triggered by something minor—like a loose gas cap or a faulty oxygen sensor. The good news? In many cases, you can reset the light yourself, especially if you’ve already addressed the issue.
This comprehensive guide will walk you through everything you need to know about resetting the engine light on your Harley-Davidson motorcycle. Whether you ride a modern Touring model, a classic Softail, or a nimble Sportster, we’ve got you covered. You’ll learn how to diagnose the problem, use the right tools, and safely clear the warning—without causing further damage.
By the end of this guide, you’ll be able to confidently reset your Harley’s engine light, understand what the codes mean, and know when it’s time to call in a pro.
Let’s get started.
Why Does the Harley Engine Light Come On?
Visual guide about How to Reset Harley Engine Light
Image source: i.ytimg.com
Before we dive into resetting the light, it’s important to understand why it came on in the first place. The engine light—technically called the Malfunction Indicator Lamp (MIL)—is part of your Harley’s onboard diagnostic system (OBD). This system constantly monitors sensors and components related to engine performance, emissions, and fuel efficiency.
When something goes outside normal parameters, the system stores a Diagnostic Trouble Code (DTC) and triggers the engine light. Common causes include:
- A loose or damaged gas cap (one of the most frequent culprits)
- Faulty oxygen (O2) sensor
- Misfiring spark plugs or ignition coils
- Clogged air filter or fuel injector issues
- Problems with the exhaust gas recirculation (EGR) system
- Electrical glitches or wiring issues
- Low battery voltage or charging system problems
In some cases, the light may come on temporarily due to extreme weather, altitude changes, or even a momentary hiccup in the system. But if it stays on, it’s a sign that something needs attention.
Important: Never ignore a steady or flashing engine light. A flashing light usually indicates a severe misfire that can damage the catalytic converter—ride cautiously and get it checked ASAP.
Tools You’ll Need to Reset the Harley Engine Light
The tools required depend on your Harley’s model year and whether it uses an OBD2 system. Here’s what you might need:
For Modern Harleys (2008 and Newer):
- OBD2 Scanner: This is the most reliable and recommended tool. It plugs into your bike’s diagnostic port and reads the trouble codes. Many scanners also allow you to clear the codes and reset the engine light. Look for one compatible with Harley-Davidson motorcycles (e.g., Foxwell NT510, Autel MaxiCOM, or Harley-specific tools like the Digital Technician).
- Smartphone with Bluetooth OBD2 App: Some scanners connect to your phone via Bluetooth, letting you view codes and reset the light using an app like Torque Pro or Harley’s own Digital Technician app.
- Owner’s Manual: Always keep your Harley’s manual handy—it contains model-specific instructions and port locations.
For Older Harleys (Pre-2008):
- Ignition Key: Some older models allow a manual reset using the key and throttle.
- Multimeter (Optional): Useful for checking battery voltage or sensor resistance if you’re troubleshooting.
- Flashlight: Helps you locate the diagnostic port or inspect components.
Optional but Helpful:
- Gloves and safety glasses
- Cleaning cloth (for the gas cap and sensor connections)
- Notepad and pen (to record codes)
Step-by-Step: How to Reset Harley Engine Light Using an OBD2 Scanner
If your Harley was manufactured in 2008 or later, it likely uses an OBD2 system. This is the most accurate and safest way to reset the engine light. Here’s how to do it:
Step 1: Locate the OBD2 Port
The OBD2 diagnostic port is usually found under the seat, near the battery, or under the fuel tank. On most Harley Touring and Softail models, it’s under the left side cover or behind the side panel. On Sportsters, it’s often under the seat or near the rear fender.
Tip: Check your owner’s manual for the exact location. If you can’t find it, look for a small, rectangular connector with 16 pins.
Step 2: Turn Off the Ignition
Make sure the bike is off and the key is removed. This prevents electrical surges or accidental damage to the scanner.
Step 3: Plug in the OBD2 Scanner
Insert the scanner’s connector into the OBD2 port. Make sure it’s fully seated and secure.
Step 4: Turn the Ignition to “On” (Do Not Start the Engine)
Turn the key to the “ON” position—this powers up the bike’s electrical system without starting the engine. The scanner should light up and begin communicating with the bike’s computer.
Step 5: Read the Diagnostic Trouble Codes (DTCs)
Follow the scanner’s instructions to retrieve the stored codes. These will appear as alphanumeric sequences like “P0134” (O2 sensor circuit malfunction) or “P0302” (cylinder 2 misfire).
Pro Tip: Write down the codes before clearing them. This helps you track patterns or share info with a mechanic.
Step 6: Address the Underlying Issue
Before resetting the light, make sure you’ve fixed the problem. For example:
– If the code is P0455 (large EVAP leak), check and tighten the gas cap.
– If it’s P0134 (O2 sensor), inspect the sensor and wiring.
– If it’s a misfire code, check spark plugs and ignition coils.
Never reset the light without fixing the issue—it will likely come back.
Step 7: Clear the Codes and Reset the Engine Light
Once the problem is resolved, use the scanner’s “Clear Codes” or “Reset” function. The scanner will send a command to the bike’s computer to erase the stored DTCs and turn off the engine light.
Step 8: Turn Off the Ignition and Unplug the Scanner
Wait a few seconds, then turn the key back to “OFF” and remove the scanner.
Step 9: Start the Bike and Verify
Start your Harley and check the dashboard. The engine light should be off. Take a short test ride to ensure the bike runs smoothly and the light doesn’t return.
Note: Some scanners require a drive cycle (a specific pattern of starting, accelerating, and decelerating) before the system fully resets. Check your scanner’s manual for details.
How to Reset Harley Engine Light on Older Models (Pre-2008)
Older Harley models (like certain Sportsters, Dynas, and FLHs from the 1990s and early 2000s) may not have a standard OBD2 port or may use a different diagnostic system. In some cases, you can reset the engine light manually—but this method is less reliable and not supported on all bikes.
Manual Reset Method (Key and Throttle)
This procedure works on some pre-2008 Harleys, but results vary. Use it only if you’ve confirmed it’s compatible with your model.
Step 1: Turn the Ignition On (Do Not Start)
Insert the key and turn it to the “ON” position. The engine light should illuminate.
Step 2: Press and Hold the Throttle
While the ignition is on, fully twist the throttle and hold it for 10–15 seconds. Some riders report that this triggers a reset sequence.
Step 3: Turn the Ignition Off
Release the throttle and turn the key to “OFF.” Wait 30 seconds.
Step 4: Turn the Ignition Back On
Turn the key to “ON” again and check if the engine light remains off.
Warning: This method is not officially supported by Harley-Davidson and may not work on all models. It also doesn’t clear stored codes—only resets the light temporarily. If the problem persists, the light will return.
Alternative: Disconnect the Battery
Another old-school method is to disconnect the battery for 10–15 minutes. This resets the bike’s computer and may clear the engine light.
Step 1: Turn Off the Bike and Remove the Key
Ensure the bike is completely off.
Step 2: Disconnect the Negative Battery Terminal
Use a wrench to loosen and remove the negative (black) cable from the battery.
Step 3: Wait 10–15 Minutes
This allows the bike’s computer to fully discharge and reset.
Step 4: Reconnect the Battery
Reattach the negative cable and tighten it securely.
Step 5: Start the Bike
Turn the ignition on and start the engine. The light should be off—but again, this doesn’t fix the root cause.
Note: Disconnecting the battery may also reset other systems, like radio presets or trip meters. Use this method cautiously.
Troubleshooting Common Issues When Resetting the Harley Engine Light
Even with the right tools, you might run into problems. Here’s how to handle common issues:
The Engine Light Comes Back On After Reset
This means the underlying issue wasn’t fixed. For example:
– A loose gas cap was tightened but still leaks.
– An O2 sensor is faulty and needs replacement.
– A misfire persists due to worn spark plugs.
Solution: Re-scan the bike to see if the same code returns. If so, investigate further or consult a mechanic.
Scanner Won’t Connect to the Bike
Possible causes:
– The OBD2 port is damaged or corroded.
– The scanner isn’t Harley-compatible.
– The bike’s battery is too low.
Solution: Clean the port with electrical contact cleaner, ensure the battery is charged, and use a scanner designed for motorcycles.
Engine Light Flashes While Riding
A flashing light indicates a severe misfire that can damage the catalytic converter. This is an emergency.
Solution: Pull over safely, turn off the bike, and have it towed to a Harley service center. Do not continue riding.
Bike Runs Rough After Reset
If the engine runs poorly after clearing codes, the issue may be more complex—like a failing fuel pump or ECM problem.
Solution: Re-scan for codes and consider professional diagnosis.
No OBD2 Port Found
Some very old Harleys (pre-1996) don’t have a diagnostic port. In these cases, you’ll need a Harley-specific tool or a mechanic with access to factory diagnostic equipment.
When to See a Harley Mechanic
While many engine light issues can be resolved at home, some situations require professional help:
- The engine light is flashing.
- The same code keeps returning after reset.
- You’re unsure how to interpret the diagnostic code.
- The bike is running poorly, overheating, or losing power.
- You don’t have access to an OBD2 scanner or aren’t comfortable working on electrical systems.
Harley-Davidson dealerships use advanced tools like Digital Technician, which can access deeper system data and perform specialized resets. A certified technician can also perform a full diagnostic and ensure your bike is safe to ride.
Preventing Future Engine Light Issues
The best way to avoid engine light problems is through regular maintenance:
- Check the gas cap: Always tighten it until it clicks. Replace it if it’s cracked or worn.
- Replace spark plugs and wires: Follow your Harley’s service schedule (usually every 10,000–15,000 miles).
- Use quality fuel: Avoid cheap or contaminated gasoline.
- Keep sensors clean: O2 sensors and air filters should be inspected regularly.
- Monitor battery health: A weak battery can trigger false codes.
- Use a fuel system cleaner: Add it to your tank every few thousand miles to keep injectors clean.
Conclusion
Resetting the Harley engine light doesn’t have to be intimidating. With the right tools and a little know-how, you can clear the warning and get back on the road with confidence. Whether you’re using an OBD2 scanner on a modern bike or trying a manual method on an older model, the key is to diagnose the problem first and fix it before resetting.
Remember: the engine light is your bike’s way of saying, “Hey, something’s not right.” Ignoring it can lead to bigger problems down the road. But by following this guide, you’ll be equipped to handle it like a pro.
So next time that little light pops up, don’t panic—grab your scanner, check the codes, fix the issue, and reset it safely. Your Harley will thank you with smooth rides and peace of mind.
Ride safe, ride smart, and keep that engine light off.