Fixing Epson ET-8550 Error Code 031004: Causes, Diagnostics, and Repair Advice

Question: My Epson ET-8550 stopped printing white ink, so I ran a nozzle clean and a power clean, but they still didn’t fix the issue. After that, I started getting error code 031004. I read your blog post about it (https://bchtechnologies.com/blogs/blog/understanding-epson-et8550-error-code-031004-solutions-and-support-from-bch-technologies). Do I need to replace the printhead FFC cable and fuses? Or should I check something else first? Is there a video specifically showing how to fix the 031004 error on an ET-8550?

Answer:

Thank you for rcontactingus, and I sincerely apologize for not getting back to you sooner. I understand how frustrating and urgent these printer issues can be—, specially when you're dealing with white ink and the 031004 error. At BCH Technologies, we aim to treat every issue carefully and with as much precision as possible. We're especially grateful for your support of our YouTube channel (https://youtube.com/@bchtechnologies). Your questions and feedback help us build better technical resources for the whole printing community.

Let’s break this down and walk through what’s likely happening—and what to do next.

Understanding Epson ET-8550 Error Code 031004

The 031004 error on the ET-8550 typically indicates a communication failure between the printhead and the mainboard. It's a serious error, and if you're using DTF white ink, it's not uncommon—white ink has a reputation for causing clogs and short circuits.

The causes can be narrowed down to these primary suspects:

1. Blown Printhead Fuses (Mainboard)

This is one of the most common culprits. There are small surface-mounted fuses on the mainboard that act as protection. If these are blown, communication to the printhead fails, and you’ll get 031004.

How to check:

• Use a multimeter to test for continuity across the fuses.

• If one or more fuses are blown, they need to be replaced before installing a new printhead—otherwise, you'll just damage the new head again.

2. Damaged or Contaminated FFC Cables

The flat flexible cables (FFC) that connect the printhead to the board can get ink on them, or develop carbon tracking (tiny conductive paths that form when ink dries on the contacts). This causes shorts and can even blow the mainboard fuses.

What to look for:

• Burn marks, discoloration, or visible ink on the cable ends.

• Warped or bent pins.

If there’s damage, replace the cable before trying anything else.

3. Shorted Printhead (Especially White Channel)

This is often the root cause. If the printhead—especially the white ink channel—shorts internally, it can fry both the cable and the mainboard fuse.

Test idea:

• Disconnect the printhead entirely.

• Power the printer back on.

If the 031004 error goes away when the printhead is disconnected, that's a good sign the head is shorted and needs to be replaced.

⚠️ Important: Never install a new printhead until you've verified the cables and fuses are working. A bad cable or fuse can damage the new printhead immediately.

Do You Need a Video for the ET-8550?

At this time, we don’t have a dedicated video specifically for the ET-8550 with 031004, but we do cover the same fuse testing and repair process on our XP-15000 and ET-2760 videos, which use similar board layouts and diagnostic steps.

You can find these guides on our YouTube channel (https://youtube.com/@bchtechnologies) by searching for “fuse testing” or the printer model name. We’re currently developing a dedicated ET-8550 DTF repair series, and that should include specific coverage of the 031004 error when it's ready.

Recap of Next Steps

1. Visually inspect the FFC cables for burns, ink contamination, or wear.

2. Test all fuses on the mainboard using a multimeter. Replace if needed.

3. Disconnect the printhead and power on—if error 031004 disappears, your printhead is likely shorted.

4. Do NOT install a new head until the cables and board are confirmed safe.

5. Look for comparable repair videos for XP-15000 or ET-2760 for now while ET-8550-specific content is being developed.

Repairing a printer with a 031004 error can be complicated, and diagnosing shorts or internal damage often requires direct access and testing tools. Because of this, we’re not able to offer remote repair support. However, we do provide in-house diagnostics and repair through our printer repair service center (https://bchtechnologies.com/printer-repair-service). This service operates on a first-come, first-served basis, and depending on the queue, there might be a short wait before we can begin. We handle both full printer repairs and individual part services like mainboard or printhead diagnostics. That said, we understand our rates may not be the cheapest, so we strongly encourage continued self-repair efforts and using our YouTube channel (https://youtube.com/@bchtechnologies) as a searchable archive of tutorials. Just use the search icon next to the "About" tab to find videos on related topics.

Thanks again for reading our blog, supporting our store, and reaching out with such a detailed and thoughtful question. Let us know if you'd like help sourcing fuses, cables, or even a replacement printhead. We're always here to help you keep printing!