How to Fix Epson L6570 Error Code 0x791E: Fuse and Printhead Troubleshooting

Question:

Hi, I have an Epson L6570 (same printer model as ET-5850 ) with error code 0x791E and need help After careful inspection of the fuse on the mainboard, I noticed that it was burnt so I replaced it. However, the error persists. Is it more than 1 fuse on board, or did another part create this error? For reference, I've included images of this logic board.

Answer:

We appreciate your consideration. Our YouTube channel (https://youtube.com/@bchtechnologies) and more of your comments are the best sources for us to continue improving. Thank you for your trust and interest in our work! Your feedback helps us keep digging deeper into our technical knowledge, and we are happy you reported this problem to us.

What is Error 0x791E

BCH Technologies' blog on Epson L6570 error codes (https://bchtechnologies.com/blogs/news/epson-l6570-error-codes) states error 0x791E. The error possibly means that the mainboard fuse blew. As suspected, you found the fuse burned on your mainboard. Now, the problem goes beyond that fuse, as we have already changed it without changing the outcome. Please let me explain why.

Epson Reports a Blown Fuse?

In Epson printers, such as L6570, an electrical signal verifies a simplified connection of two lines on the mainboard. If the fuse is broken, the signal between these two lines will not flow, and a 0x791E error will show. You may have reset the connection (as you did when you replaced the fuse), but if the error persists, that means something else in the circuit is still dead.

Damaged Printhead:

Even after replacing the fuse, a dead head can create the eternal 0x791E error, with many claiming it is a cause. If the printhead was damaged enough, this internal connection on the inside might get broken and trigger the same electrical disconnect that caused a fuse to fail in the first place. The printer still thinks the fuse is blown because the printhead can not pass or improperly activate a complete circuit.

Burnt FFC(Flat Flexible Cable):

You may also want to look at the FFC cable, which connects the mainboard to the printhead—it could be broken. 

Steps to Take:

Change the Printhead:

Most damages won't be possible to tell from the looks of the printhead. Therefore, I suggest replacing the printhead with a new one.

Check the FFC Cables:

Check the lines of FFC cables linking the mainboard with the print head carefully. If there are any signs of damage (such as burn marks, cracks, or misalignment), replace the FFC cables with new ones. As little as a break or burn in the cable may disrupt the ability to make the correct electrical connection, causing the printer to think it has had another "blown fuse."

A printhead that does not work can also cause error code 0x791E. Initial SolutionIf you have replaced the fuse but still have an issue with error code 0x791E, your printhead may be dead, or maybe the cables FFC are damaged; they have similar symptoms. At this stage, replacing the printhead/FFC cables is the best possible solution.

It can be hard to resolve the printing problem as they require personal attention. For this reason, we cannot offer suggestions in a helpdesk format to help you troubleshoot printer repairs remotely. Our local diagnostic facility ( printer repair service https://bchtechnologies.com/printer-repair-service ) provides walk-in evaluation and repair service, but due to high demand, we operate on first-come-first-served basics. We might be able to get your printer to drop it off or mail it in a few weeks just for you.

As always, we recommend you check our page for more info and self-help resources, including many of our guides to watch on YouTube (https://youtube.com/@bchtechnologies). There are loads of things here that you may find helpful, and if it doesn't have the exact video you want, this also means that other similar content will be recommended to you through YouTube from somewhere else.

Thanks again for your contacts and, hopefully, support. This helps you with a potential resolution! If you have any further questions, do not hesitate to contact us again.