Epson ET-8550 Printer Error 031006 After Flushing With Alcohol: No Movement, No Sound, Carriage Won't Lock

Question

I've watched some of your videos and they've been really helpful, but I'm stuck with a serious problem on my Epson EcoTank ET-8550 and it's putting my business in a bind. I removed all the ink and cleaned/flushed the system with a printhead cleaning kit because my turquoise was printing blue. I also flushed a bit with 91% isopropyl alcohol, left the cartridges/tanks unlocked while waiting for new ink, then refilled and powered the printer back on. Now I get Printer Error 031006. There's no paper jam or debris, and I haven't printed in a couple of months. The printer makes no sound, nothing moves, and the carriage won't move normally or lock if I push it back to the right. The screen goes straight to the printer error code with no other activity.

Answer

From your description, two things stand out:

1. You introduced flush solution and 91% isopropyl alcohol into a system that has delicate electronics and sensors near the head and carriage area.

2. The printer now shows Error Code 031006 and exhibits a "dead" behavior pattern: no initialization sounds, no carriage movement, and immediate error on screen.

On the ET-8550, Error 031006 is commonly associated with the mainboard protection circuit being triggered, often due to a short or abnormal load detected in the printhead/cable/head-drive path. In plain terms, the printer is refusing to even start moving because it senses an electrical condition that could cause further damage.

Below is the most likely chain of events and the practical checks that match your symptoms.

Why Error 031006 often happens after flushing/cleaning

When you flush a printhead system, the biggest risk isn't only clog removal-it's liquid migration:

• Liquid can wick along the printhead assembly, dampers, and especially the FFC cables/connectors (flat flex cables).

• Even a small amount of moisture or residue can create a conductive film that causes:

  • a temporary short (sometimes recoverable after proper drying and cleaning), or

  • a hard short that blows protective components on the mainboard (fuses), which then causes a persistent 031006 condition.

Your "no movement/no sound" detail is important. Many printers will attempt a short startup before faulting. When you get an immediate error with essentially no mechanical action, it often means the board is preventing drive power from even reaching certain circuits.

Step 1: Inspect the printhead FFC cables (pin damage/tarnish is a big clue)

Your proposed direction is right on target: remove the printhead (or at least access the head cable connections) and inspect the FFC cable contact pads, especially Pin #7.

What to look for:

• Tarnish/discoloration on pin pads (darkening, greenish/bronze staining)

• More than one pin showing corrosion/tarnish

• Any signs of ink/cleaner residue at the cable ends

• Creases or micro-cracks in the cable

Why pin #7 matters:
On many Epson head/cable layouts, specific pins carry critical sensing/drive signals. If a key pin is compromised (oxidized, contaminated, or partially open/shorted), the printer may detect a fault and immediately throw codes like 031006. If Pin #7 is tarnished-and especially if multiple pins are tarnished-the safest assumption is that the cable set is no longer reliable and should be replaced.

Important note: Re-seating a damaged/tarnished FFC cable can sometimes make things worse by arcing or intermittently shorting, so inspection and replacement is often smarter than repeated re-plugging.

Step 2: Test the printhead electrically (to rule in/out a head short)

If the head has an internal short, it can instantly trigger mainboard protection. We provide a step-by-step instruction sheet for testing a printhead with a multimeter. Here is the resource you referenced:

• Instruction Sheet for L1800/1390 Printhead Testing With Multimeter (Digital Download) (https://bchtechnologies.com/products/instruction-sheet-for-l1800-1390-printhead-testing-with-multimeter-digital-download-instant-download-delivered-to-your-email-copy)

Even though that sheet is labeled for a different head family, the underlying principle is the same: you're checking for abnormally low resistance (short) or open circuits across the firing channel groups. If your readings suggest a short, the printer is doing exactly what it should by refusing to initialize-continuing to power a shorted head can damage the board further.

Practical interpretation:

• Shorted head → frequently leads to board fuse damage and persistent error codes like 031006

• Head tests normal → then focus shifts heavily to FFC cables/connectors and mainboard fuses

Step 3: Mainboard fuses F1/F2 (very common cause of 031006 "dead printer" behavior)

Your proposed fix here is also correct: on ET-8550 units, F1/F2 fuses on the mainboard are commonly tied to errors 031004 / 031005 / 031006 and "no power / no movement" type symptoms. If those fuses open (blow), the printer can power the display but will not drive the carriage/head system correctly, resulting in immediate fault conditions.

You mentioned the correct part bundle here:

• F1/F2 Fuse Bundle for Epson ET-8550/ET-8500 (Fix Errors 031004/031005/031006) (https://bchtechnologies.com/products/f1-f2-fuse-bundle-for-epson-et-8550-et8550-et-8500-fix-errors-031004-031005-031006-no-power-issue?_pos=1&_sid=44d91ca0d&_ss=r)

Critical caution:
Replacing fuses without addressing the root cause can lead to the new fuses blowing immediately. That's why the usual safe sequence is:

1. inspect/replace compromised FFC cables (especially if pin tarnish exists),

2. test the printhead for shorts,

3. then replace the F1/F2 fuses only when you're confident you won't reintroduce the same short condition.

Why leaving cartridges unlocked and using 91% isopropyl alcohol can contribute

A couple of points based on what you described:

• Leaving the system "unlocked/open" while waiting can allow air migration and drying, which can worsen clogs, but your current problem is beyond a clog-this is electrical/protection behavior.

• 91% isopropyl alcohol still contains water, and alcohol can carry dissolved contaminants into places you don't want them. It can also affect some plastics/adhesives over time. Even if the alcohol evaporates, it may leave behind conductive residue depending on what it picked up during flushing.

So while your initial goal (correcting color crossover and suspected clog) makes sense, the current symptom set aligns much more with electronics protection fault than ink flow.

Repair options (parts or service)

If you prefer to send it in rather than do board-level work, you can use our repair service collection here:

• BCH Technologies Printer Repair Service (https://bchtechnologies.com/collections/printer-repair-service)

Addressing printer issues can be complicated because most failures are hands-on and involve physical inspection, testing, and sometimes component-level repair. Because of that, we're not able to provide remote troubleshooting, suggestions, or support for printer repairs. We do offer an in-person evaluation and repair service through our local diagnostic facility at Printer Repair Service (https://bchtechnologies.com/printer-repair-service). Due to high demand, we operate on a first-come, first-served basis, and it may take a few weeks before we're able to accept your printer for drop-off. Our services are structured to repair either an entire printer or specific parts, with clear instructions on how to proceed. We also recognize our rates aren't the most economical, so we strongly recommend self-help through online research. A great place to start is YouTube, including our channel homepage at BCH Technologies on YouTube (https://youtube.com/@bchtechnologies). To find the most relevant videos, use the search icon near "About" on the right-hand side of the menu bar-this is the fastest way to locate specific topics since we've published hundreds of videos over the past nine years. YouTube may also suggest helpful videos from other channels that cover similar repairs.

Thank you again for reaching out and for supporting BCH Technologies. I truly hope this points you to the most likely causes of Error Code 031006 and helps you choose the most efficient next step-whether that's checking/replacing the FFC cables (especially Pin #7), testing the printhead, and/or addressing the F1/F2 mainboard fuses.