This guide walks you through how to reset the check engine light using the Actron Autoscanner Plus, a reliable OBD2 scanner. You’ll learn setup, scanning, clearing codes, and troubleshooting—all in simple steps.
Key Takeaways
- Understand the basics: The Actron Autoscanner Plus reads and clears diagnostic trouble codes (DTCs) from your vehicle’s onboard computer.
- Ensure compatibility: This scanner works with most 1996 and newer OBD2-compliant vehicles, including cars, trucks, and SUVs.
- Follow safety steps: Always turn off the engine, locate the OBD2 port, and connect the scanner properly before starting.
- Read codes first: Never clear codes without understanding what they mean—use the scanner to retrieve and interpret them.
- Reset the light safely: After repairs, use the “Clear Codes” function to reset the check engine light and verify the fix.
- Monitor afterward: Drive your vehicle for a few days to ensure the light doesn’t return, indicating the issue is truly resolved.
- Troubleshoot issues: If the scanner won’t connect or the light comes back, check connections, battery voltage, or consult a mechanic.
Introduction: Why Resetting the Check Engine Light Matters
The check engine light is one of the most misunderstood warning signals in your vehicle. It’s not just a random annoyance—it’s your car’s way of saying, “Hey, something needs attention.” But once you’ve fixed the problem, that light can linger like an uninvited guest. That’s where the Actron Autoscanner Plus comes in.
This compact, user-friendly OBD2 scanner lets you read, interpret, and clear diagnostic trouble codes (DTCs) from your vehicle’s computer. Whether you’ve replaced an oxygen sensor, tightened a loose gas cap, or fixed a misfire, resetting the check engine light confirms your repair worked.
In this guide, you’ll learn exactly how to reset the check engine light using the Actron Autoscanner Plus. We’ll cover everything from setup and connection to interpreting codes and safely clearing them. You’ll also get practical tips, troubleshooting advice, and answers to common questions.
By the end, you’ll feel confident using this tool to maintain your vehicle and avoid unnecessary trips to the mechanic.
What Is the Actron Autoscanner Plus?
Visual guide about How to Reset Check Engine Light Using Actron Autoscanner Plus
Image source: content.propertyroom.com
Before diving into the steps, let’s get familiar with the tool itself.
The Actron Autoscanner Plus is a handheld OBD2 (On-Board Diagnostics II) scanner designed for DIYers and car enthusiasts. It plugs into your vehicle’s OBD2 port—usually located under the dashboard—and communicates with the engine control unit (ECU) to retrieve diagnostic information.
Key features include:
– Reading and clearing diagnostic trouble codes (DTCs)
– Displaying live data (on some models)
– Built-in code definitions for quick reference
– Compact, portable design
– No batteries required—it draws power from the vehicle
It’s compatible with most gasoline-powered vehicles made in 1996 or later, as well as many diesel and hybrid models. Always check your vehicle’s year, make, and model to confirm compatibility.
When Should You Reset the Check Engine Light?
Resetting the check engine light isn’t something you should do on a whim. It’s important to understand why the light came on in the first place.
Common reasons include:
– Loose or faulty gas cap
– Oxygen (O2) sensor failure
– Catalytic converter issues
– Mass airflow (MAF) sensor problems
– Spark plug or ignition coil faults
If you’ve addressed the root cause—like replacing a sensor or tightening the gas cap—then resetting the light makes sense. But if you clear the code without fixing the issue, the light will likely return.
So, only reset the check engine light after:
1. You’ve diagnosed the problem (using the scanner or a mechanic)
2. You’ve made the necessary repair
3. You want to confirm the fix worked
Step 1: Gather Your Tools and Prepare Your Vehicle
Before connecting the Actron Autoscanner Plus, take a few minutes to prepare.
What You’ll Need
- Actron Autoscanner Plus scanner
- Vehicle with a 1996 or newer OBD2 system
- Owner’s manual (optional, but helpful)
Preparation Steps
- Park your vehicle on a flat surface. Make sure it’s in “Park” (for automatics) or “Neutral” (for manuals) with the parking brake engaged.
- Turn off the engine. Never connect or disconnect the scanner while the engine is running.
- Locate the OBD2 port. It’s usually under the dashboard, near the driver’s side knee area. It’s a 16-pin connector, often black or gray, and may be labeled “OBD” or “DLC.”
- Check the scanner. Ensure the Actron Autoscanner Plus is clean, undamaged, and has no loose wires.
Pro tip: If you can’t find the OBD2 port, check your owner’s manual or look online using your vehicle’s make, model, and year.
Step 2: Connect the Actron Autoscanner Plus
Now it’s time to plug in the scanner.
How to Connect
- Take the scanner and locate the 16-pin connector at the end of the cable.
- Align the connector with the OBD2 port. The shape is keyed, so it only fits one way.
- Gently push it in until it clicks or feels secure. Don’t force it—if it doesn’t fit, double-check the orientation.
- Once connected, the scanner should power on automatically. You’ll see lights or text on the screen.
What If It Doesn’t Turn On?
If the scanner doesn’t power up:
– Make sure the ignition is in the “ON” position (you don’t need to start the engine).
– Check that the OBD2 port has power—some vehicles require the key to be turned to “ON” to activate the port.
– Try a different OBD2 port if your vehicle has more than one (rare, but possible).
Step 3: Turn the Ignition On (But Don’t Start the Engine)
This step is crucial.
Why the Ignition Must Be On
The Actron Autoscanner Plus needs power from the vehicle’s electrical system to communicate with the ECU. However, starting the engine can cause voltage fluctuations that interfere with the scan.
So:
– Turn the key to the “ON” position (dashboard lights should illuminate).
– Do not start the engine.
– Wait a few seconds for the scanner to initialize.
You’ll usually see a welcome screen or “Actron” logo appear. This means the scanner is ready.
Step 4: Read the Diagnostic Trouble Codes (DTCs)
Before clearing any codes, you need to know what they are.
How to Retrieve Codes
- Press the “Read” or “Scan” button on the Actron Autoscanner Plus. The exact button may vary by model, but it’s usually clearly labeled.
- The scanner will communicate with the vehicle’s computer. This may take 10–30 seconds.
- Once complete, the screen will display one or more diagnostic trouble codes (DTCs).
Understanding the Codes
DTCs follow a standard format: a letter followed by four numbers (e.g., P0302).
– The first letter indicates the system:
– P = Powertrain (engine, transmission)
– B = Body (airbags, climate control)
– C = Chassis (ABS, suspension)
– U = Network/Communication
– The next digit shows if it’s a generic (0) or manufacturer-specific (1) code.
– The last three digits identify the specific issue.
For example, P0302 means “Cylinder 2 Misfire Detected.”
Use the Built-In Code Library
One of the best features of the Actron Autoscanner Plus is its built-in code definitions. After retrieving a code:
– Press the “Help” or “Definition” button (if available).
– The scanner will display a plain-English explanation of the code.
This saves you from having to look it up online or in a manual.
Write Down the Codes
Before clearing anything, write down all the codes and their meanings. This helps you:
– Confirm the problem
– Track repairs
– Diagnose if the light returns
Step 5: Fix the Underlying Problem
Now that you know what’s wrong, it’s time to fix it.
Common Repairs Based on Codes
- P0455 (Large EVAP Leak): Check the gas cap. Tighten it or replace it if cracked.
- P0171 (System Too Lean): Inspect for vacuum leaks, clean the MAF sensor, or check fuel pressure.
- P0300 (Random Misfire): Replace spark plugs, ignition coils, or check fuel injectors.
- P0420 (Catalyst Efficiency Below Threshold): May require catalytic converter replacement—consult a mechanic.
DIY vs. Professional Help
Some fixes are easy (like tightening a gas cap), while others require tools, experience, or special equipment. If you’re unsure, don’t guess—take your vehicle to a trusted mechanic.
Remember: Clearing the code without fixing the problem is like turning off a smoke alarm while the house burns down. The light will come back.
Step 6: Clear the Check Engine Light
Once the repair is complete, it’s time to reset the light.
How to Clear the Codes
- Make sure the scanner is still connected and the ignition is on.
- Press the “Clear” or “Erase” button on the Actron Autoscanner Plus.
- Confirm the action when prompted (some models ask “Are you sure?”).
- The scanner will send a command to the ECU to clear all stored trouble codes.
- Wait for a confirmation message like “Codes Cleared” or “Reset Complete.”
What Happens Next?
– The check engine light should turn off within a few seconds.
– If it doesn’t, try turning the ignition off and on again.
– Some vehicles may require a short drive cycle for the light to fully reset.
Important Notes
– Clearing codes also resets the vehicle’s readiness monitors. These are self-tests the ECU runs to check emissions systems.
– If you’re preparing for an emissions test, you may need to drive the vehicle for a few days to allow the monitors to complete.
Step 7: Verify the Reset Worked
Don’t assume the job is done just because the light is off.
Drive and Monitor
Take your vehicle for a test drive—about 20–30 minutes of mixed city and highway driving. This helps the ECU relearn driving patterns and complete self-checks.
Watch for the Light
If the check engine light comes back on:
– The problem wasn’t fully fixed
– A new issue has developed
– The repair wasn’t successful
Re-Scan if Needed
If the light returns, reconnect the Actron Autoscanner Plus and read the codes again. Compare them to the original ones to see if it’s the same issue or a new one.
Troubleshooting Common Issues
Even with the right tool, things don’t always go smoothly. Here’s how to handle common problems.
Scanner Won’t Connect or Power On
- Check the ignition: Make sure it’s in the “ON” position.
- Inspect the OBD2 port: Look for dirt, corrosion, or bent pins. Clean gently with compressed air.
- Try another vehicle: Test the scanner on a different car to see if it’s the tool or the vehicle.
- Check fuse: Some OBD2 ports are powered by a fuse. Check your owner’s manual for the correct fuse location.
Codes Won’t Clear
- Active vs. stored codes: If the problem still exists, the ECU will keep setting the code. Fix the issue first.
- Scanner limitations: Some advanced codes (like those related to transmission or ABS) may not be clearable with basic scanners.
- Try again: Disconnect the scanner, wait 10 seconds, reconnect, and retry.
Check Engine Light Comes Back On
- Incomplete repair: The original problem may not be fully resolved.
- Intermittent issue: Some problems only occur under certain conditions (e.g., cold starts, high speed).
- New problem: A different component may have failed.
Scanner Displays “No Link” or “No Communication”
This means the scanner can’t talk to the vehicle’s computer.
- Ensure the vehicle is OBD2-compliant (1996 or newer for most cars).
- Check for aftermarket modifications that may interfere with the ECU.
- Try a different scanner to confirm the issue.
Tips for Best Results
To get the most out of your Actron Autoscanner Plus, follow these best practices.
Keep the Scanner Clean and Stored Properly
– Wipe the screen and connector with a dry cloth.
– Store in a cool, dry place—avoid extreme heat or moisture.
– Use the included case or pouch if available.
Update the Scanner (If Possible)
Some Actron models allow firmware updates. Check the manufacturer’s website for updates that improve compatibility or add new features.
Use It Regularly
Even if the check engine light isn’t on, scanning your vehicle occasionally can catch early signs of trouble—like pending codes or sensor drift.
Combine with a Repair Manual
For complex issues, pair the scanner with a repair manual (like Haynes or Chilton) for step-by-step guidance.
Conclusion: Take Control of Your Vehicle’s Health
Resetting the check engine light doesn’t have to be a mystery. With the Actron Autoscanner Plus, you have a powerful tool that puts diagnostic information at your fingertips.
By following this guide, you’ve learned:
– How to safely connect and use the scanner
– How to read and interpret trouble codes
– How to clear the check engine light after repairs
– How to troubleshoot common issues
Remember, the goal isn’t just to turn off the light—it’s to keep your vehicle running smoothly, safely, and efficiently. Use the Actron Autoscanner Plus as part of a regular maintenance routine, and you’ll save time, money, and stress in the long run.
So the next time that little orange light pops up, don’t panic. Grab your scanner, follow these steps, and take control.