Reset the check engine light on your 1998 Honda Accord in 2026 by first diagnosing the root cause with an OBD2 scanner—never ignore persistent codes. Once repairs are confirmed, disconnect the battery for 10–15 minutes or use a scanner to clear the code safely and effectively, ensuring the system resets without triggering new warnings. Always verify the fix by checking for a stable light-free dashboard after restart.

How to Reset Check Engine Light on 1998 Honda Accord in 2026

Key Takeaways

• Diagnose first: Always check error codes before resetting the light.
• Use OBD2 scanner: Reset via scanner for accurate, permanent results.
• Battery disconnect: Turn off ignition, wait 10+ minutes after disconnecting.
• Drive cycle required: Complete 50-100 miles to fully clear codes.
• Check gas cap: Tighten or replace to fix common false triggers.
• Verify repairs: Ensure issues are fixed before resetting the light.

Why This Matters / Understanding the Problem

That little orange engine symbol on your dashboard isn’t just an annoyance—it’s your 1998 Honda Accord’s way of saying, “Hey, something’s not right.” Whether it’s a loose gas cap or a failing oxygen sensor, the Check Engine Light (CEL) is part of your car’s onboard diagnostics system (OBD-I for 1998 models) designed to protect your engine and reduce emissions.

Ignoring it can lead to poor fuel economy, reduced performance, or even costly damage. But once you’ve fixed the issue, you’ll want to know how to reset Check Engine Light on 1998 Honda Accord in 2026—especially if you’re prepping for a smog test or just want peace of mind.

Here’s the catch: simply disconnecting the battery won’t always work, and some DIY methods can erase important diagnostic data. That’s why this guide walks you through safe, effective, and legal ways to clear the light—after the root problem is resolved.

By the end, you’ll understand not just how to reset it, but why you should do it correctly. This ensures your Accord runs cleanly and avoids inspection failures in 2026, when emissions standards are stricter than ever.

What You Need

Before jumping into the process, gather these tools and materials. Most are common household or garage items, and none require advanced mechanical skills.

• OBD-I Code Reader or Scan Tool (for 1998 models, look for one compatible with OBD-I, like the Innova 3100 or Actron CP9690)
• 10mm wrench or socket (for battery terminal work)
• Insulated gloves (for safety when handling the battery)
• Pen and paper or phone (to record error codes before resetting)
• Replacement parts (if the issue was a faulty component, like a gas cap, spark plug, or oxygen sensor)
• Owner’s manual (for fuse box location and reset procedures specific to your trim)
• Optional: Memory saver device (to preserve radio presets and clock settings)

Pro tip: If you don’t own a scan tool, many auto parts stores (like AutoZone, O’Reilly, or Advance Auto) offer free OBD-I code reading for 1998 models. Use this to diagnose the issue before resetting.

Warning: Never reset the Check Engine Light without first identifying and fixing the underlying problem. Resetting it without repair is illegal in many states during emissions testing and can mask serious engine issues.

Step-by-Step Guide to How to Reset Check Engine Light on 1998 Honda Accord in 2026

Resetting the CEL isn’t just about clearing a warning—it’s about ensuring your car is running cleanly. Follow these steps carefully, especially if you’re prepping for a 2026 smog check.

Step 1: Diagnose the Problem First (Don’t Skip This!)

The first rule of how to reset Check Engine Light on 1998 Honda Accord in 2026 is: don’t reset it until you know why it came on.

• Locate the OBD-I diagnostic port under the dashboard, near the driver’s left knee.
• Plug in your OBD-I scanner. For 1998 models, this is usually a 3- or 12-pin connector (Honda used a 3-pin in earlier years, but 1998 is typically 12-pin—double-check with your manual).
• Turn the ignition to “ON” (don’t start the engine) and press the “Read” button on the scanner.
• Record the code(s). Common codes for 1998 Accords include:
  • P0171 – System Too Lean (Bank 1)
  • P0420 – Catalyst Efficiency Below Threshold
  • P0300 – Random/Multiple Cylinder Misfire
  • P1456 – EVAP System Leak (often a loose gas cap)

Example: If you get code P1456, tighten your gas cap and drive 50–100 miles. The light may turn off on its own. If it stays on, proceed to repair.

Tip: Write down the code and research it online or ask a mechanic. Fixing the root cause is cheaper and safer than just resetting the light.

Step 2: Fix the Underlying Issue

Now that you know what’s wrong, fix it. Here are common fixes for frequent 1998 Accord CEL codes:

• Gas cap issue (P1456): Tighten or replace the cap. Use an OEM Honda cap—aftermarket ones often leak.
• Misfire (P0300–P0304): Replace spark plugs, wires, or coils. Use NGK or Denso parts for best results.
• O2 sensor (P0133–P0167): Replace the upstream or downstream sensor. Use a wrench and anti-seize compound.
• EVAP leak: Check hoses near the charcoal canister (passenger side, under the rear seat). Replace cracked lines.

After repairs, drive the car for at least 30–50 miles with varied conditions (city and highway). This helps the ECU “relearn” normal operation.

Note: Some issues (like catalytic converter failure) require professional help. Don’t try to reset the light if the cat is clogged—this can lead to engine damage.

Step 3: Perform a Drive Cycle (Let the ECU Reset Itself)

Sometimes, the best way to reset the Check Engine Light is to let the car do it. This is called a “drive cycle,” and it’s required for many emissions monitors to complete.

Here’s a simplified drive cycle for a 1998 Honda Accord:

1. Start the engine when cold (ambient temp below 85°F). Let it idle for 2.5 minutes with A/C and defroster off.
2. Drive at 55 mph for 3 minutes.
3. Accelerate to 65 mph and maintain for 5 minutes.
4. Decelerate to 20 mph without braking (coast).
5. Accelerate to 35 mph and hold for 2 minutes.
6. Come to a complete stop and idle for 2 minutes.

After this, turn off the engine. Wait 10 seconds, then restart. The CEL should stay off if all monitors have passed.

This method is free and often effective—especially if the issue was minor (like a loose cap).

Warning: Don’t skip steps. The ECU needs specific conditions to complete each monitor. If you drive too short or too fast, it won’t reset.

Step 4: Use a Scan Tool to Clear Codes (Fastest Method)

If the drive cycle didn’t work, or you need immediate results (e.g., for a smog test), use your OBD-I scanner to reset the light.

• Plug the scanner into the diagnostic port.
• Turn the ignition to “ON” (engine off).
• Navigate to “Clear Codes” or “Reset CEL” on the scanner.
• Confirm the reset. The scanner will erase stored codes and turn off the light.

After resetting, turn the ignition off, wait 30 seconds, then restart the car. The light should stay off.

This is the most reliable method for how to reset Check Engine Light on 1998 Honda Accord in 2026, especially if you’ve already fixed the problem.

Pro Tip: After clearing, drive another 20–30 miles to ensure the ECU completes its readiness monitors. Some states require “ready” monitors for emissions tests.

Step 5: Battery Disconnect Method (Last Resort)

If you don’t have a scanner, you can reset the light by disconnecting the battery. But this erases all ECU memory—including radio presets, idle settings, and fuel trims.

1. Turn off the engine and remove the key.
2. Put on insulated gloves.
3. Use a 10mm wrench to loosen the negative (–) battery terminal (black cable).
4. Disconnect the cable and wait at least 10 minutes. This drains residual power from the ECU.
5. Reconnect the terminal and tighten it securely.
6. Start the car. The CEL should be off.

Note: You’ll need to reset your clock, radio, and possibly the idle RPM (let the car idle for 10 minutes to relearn).

This method works because it forces the ECU to reboot. But it’s not ideal—use it only if a scanner isn’t available.

Warning: Never disconnect the positive (+) terminal first. This can cause a dangerous spark near the battery. Always start with the negative.

Step 6: Verify the Reset Worked

After any reset method, double-check that the light stays off and the problem is truly fixed.

• Drive the car for at least 20 miles over 2–3 days.
• Use your scanner to check for pending codes (codes that haven’t triggered the light yet).
• Watch for symptoms like rough idle, poor fuel economy, or stalling.

If the light returns, the issue wasn’t fully resolved. Go back to Step 1.

For emissions testing in 2026, ensure all readiness monitors show “Ready” on your scanner. Some states reject vehicles with incomplete monitors, even if the light is off.

Pro Tips & Common Mistakes to Avoid

Even experienced DIYers make mistakes when resetting the Check Engine Light. Here’s how to avoid them:

• Don’t ignore pending codes: Just because the light is off doesn’t mean the problem is gone. Use your scanner to check for “pending” codes that could trigger the light again.
• Use OEM parts when possible: Aftermarket oxygen sensors or gas caps often don’t meet Honda’s specs, leading to repeat CELs.
• Don’t skip the drive cycle: If you reset the light but haven’t driven properly, the ECU may not complete emissions monitors. This can fail a 2026 smog test.
• Avoid “check engine light eliminators”: These are illegal in most states and can damage your ECU. They don’t fix problems—they just hide them.
• Label your battery cables: When disconnecting, tape labels to the positive and negative cables. Mixing them up can fry your ECU.
• Reset after repairs, not before: Some people reset the light before fixing anything, then wonder why it comes back. Fix first, reset second.

Pro Tip: Keep a log of CEL codes and fixes. Use a notebook or phone app. This helps track recurring issues and saves money on diagnostics.

Real-life example: A 1998 Accord owner tightened his gas cap, reset the light, and passed smog. But the light came back a week later. He found a cracked EVAP hose—fixing that permanently solved the issue.

FAQs About How to Reset Check Engine Light on 1998 Honda Accord in 2026

Got questions? We’ve got answers—based on real-world experience and Honda’s service manuals.

Q1: Can I reset the Check Engine Light without a scanner?
Yes, but it’s not ideal. You can disconnect the battery (Step 5), but this erases all ECU memory and may not complete readiness monitors. A $30 OBD-I scanner is a better investment.

Q2: Will disconnecting the battery always turn off the light?
Usually, but not always. If the ECU still detects a problem (e.g., a bad O2 sensor), the light may come back after a few drive cycles. Always fix the issue first.

Q3: How long does it take for the light to reset itself?
It depends. After a fix, the ECU may turn off the light after 1–3 drive cycles (50–100 miles). If it doesn’t, use a scanner.

Q4: Is it legal to reset the Check Engine Light?
Yes—if you’ve fixed the problem. It’s illegal to reset it to pass an emissions test without repairs. In 2026, many states use OBD-I scanners to verify readiness monitors.

Q5: Why did my light come back after resetting?
The root cause wasn’t fixed. For example, if you reset after a loose gas cap but didn’t tighten it properly, the light will return. Always diagnose and repair.

Q6: Can I use an OBD-II scanner on my 1998 Accord?
Not directly. 1998 Accords use OBD-I, but some OBD-II scanners have OBD-I compatibility (look for “OBD1 & OBD2” on the box). Otherwise, buy an OBD-I-specific tool.

Q7: What if the light won’t turn off after repairs?
Check for:

• Faulty sensors (O2, MAP, ECT)
• Vacuum leaks (listen for hissing near the intake)
• Wiring issues (frayed wires near the ECU)
• Failed catalytic converter (use a backpressure test)

If unsure, consult a mechanic. Some issues (like a clogged cat) require professional tools to diagnose.

Final Thoughts

Knowing how to reset Check Engine Light on 1998 Honda Accord in 2026 is more than a handy trick—it’s part of responsible car ownership. Your Accord may be over 25 years old, but it still needs care to run cleanly and pass emissions tests.

Remember: the light is a warning, not a decoration. Fix the problem first, then reset it safely. Use a scanner when possible, avoid shortcuts, and always verify the fix.

By following this guide, you’ll keep your Accord reliable, legal, and efficient—whether you’re commuting in the city or cruising down the highway.

Actionable next step: Grab your scanner, check for codes, and start with the most common fix (tighten the gas cap). Most CELs are simple to solve—and resetting them the right way saves time, money, and stress.

Happy driving, and keep that engine light off!