Epson EcoTank ET-8550 Error Code 031006 After Replacing F1 Fuse: What to Do Next

Question:

I replaced the F1 fuse on my Epson EcoTank ET-8550 because I was getting error code 031006. But even after installing the new fuse, the printer still shows the same error. What should I try next?

Answer:

Understanding Epson Error Code 031006

Error 031006 on Epson printers typically points to a printhead communication or firing issue. This error can be triggered by:

• A blown F1 fuse on the mainboard.

• A shorted printhead.

• Faulty MOSFETs or driver ICs on the mainboard.

You’ve already done the right first step by replacing the F1 fuse, which is often the first casualty when the printhead experiences a short circuit. However, if the error persists after installing the new fuse, here's what that usually means.

1. The Printhead May Be the Root Cause

In many cases, it’s the printhead itself that caused the F1 fuse to blow in the first place. If you replaced the fuse but reconnected the same printhead, it could instantly short again—sometimes blowing the new fuse immediately or continuing to trigger the error without visible damage.

Recommended step:
Replace the printhead with a new or known-good one before reconnecting the power. If you reuse the same shorted printhead, it risks damaging the mainboard again.

2. Mainboard Damage Beyond the Fuse

If the fuse and printhead have both been replaced, but the printer still throws Error 031006, the damage may be deeper in the mainboard. Most commonly, the driver ICs (integrated circuits that control the printhead) or their associated MOSFETs (transistor switches that handle high voltage) have failed.

Unfortunately, testing and replacing these components requires soldering skills and circuit diagnostics tools. Unless you're trained in board-level electronics repair, this is generally considered a professional-level repair task.

We’ve seen instances where both the printhead and the driver IC were damaged during the same failure event. In those cases, even replacing one component wasn’t enough.

What You Can Do

• Step 1: Ensure your replacement F1 fuse is still intact.

• Step 2: Disconnect the current printhead and visually inspect for scorching or abnormal resistance.

• Step 3: Try installing a new printhead before powering up again.

• Step 4: If none of the above resolves the issue, consider sending in the mainboard for professional inspection and possible repair.

Because hardware problems like these require hands-on diagnostics, we are unable to offer remote troubleshooting or repair over email. However, we do offer expert diagnostics and repairs at our in-person service facility (https://bchtechnologies.com/printer-repair-service). Due to high demand, our services operate on a first-come, first-served basis, and appointments may take a few weeks to process. Whether you're sending a full printer or just the mainboard, we offer structured options to meet your needs. That said, our rates may not be the most budget-friendly. For DIY solutions, we highly recommend visiting our YouTube channel (https://youtube.com/@bchtechnologies) and using the search icon near the "About" tab to find videos by model or error code. With over nine years of technical content, this is the quickest way to discover helpful troubleshooting guides, both from us and other creators.

Thanks again for reaching out—we hope you’re able to restore your Epson ET-8550 soon. Let us know if you'd like help sourcing a compatible printhead or if you're considering sending in your board for repair.