Epson L1800 Error Code 0x42 After Turbo Tool Cleaning: Is the Printhead Failed and Can It Be Fixed?

Question

I cleaned my Epson L1800 printhead using a turbo tool, then reassembled the printer and now the lights are blinking. I checked the status with WIC and got a status report. Can you tell me if my printhead is done, or if there's a fix? Also, do you have the L1800 printhead in stock?

Answer

Based on what you described (turbo tool cleaning → reassembly → blinking lights) and your WIC status report, your printer is logging Error Code 0x42, which typically indicates an abnormal temperature reading from the printhead thermistor.

What Error Code 0x42 usually means

The printhead has a built-in thermistor (temperature sensor). Its job is to monitor printhead temperature and report it back to the printer's mainboard. When the printer detects a temperature that's out of expected range-especially during heavy ink movement events like flushing/cleaning-it triggers a protective shutdown because overheating (or what looks like overheating) can destroy the head, the mainboard, or both.

In your case, WIC is showing 0x42 along with the context that looks like X-Hot detection during flushing (thermal fault occurring during a flush/clean cycle). That combination is a strong indicator that the printer believes the head is in a dangerous thermal condition.

Why this often happens after a turbo tool cleaning

Turbo tool cleaning is effective, but it also introduces risk because it can push fluid where it's not supposed to go. The most common failure scenario is:

• Moisture / cleaning solution migrates into the printhead's internal electrical area (or the ribbon/connector area).

• That moisture creates conductive paths (a partial short) between circuits that must remain isolated.

• The printer then reads an impossible or unsafe thermistor value, and 0x42 is logged.

This aligns with your observation that the problem started immediately after the cleaning and reassembly.

About the "fatal errors" list in Epson/WIC logs

You're exactly right to focus on the pattern. Epson typically stores the five most recent fatal errors, and Error #1 is the newest. When the two most recent fatal errors point to thermal/overheat detection during flushing, while older entries are unrelated (like PF PID reverse/overload, which is paper-feed related), that trend strongly suggests the current blinking-light condition is being driven by the printhead temperature/thermistor fault-not paper feed.

Is there a fix, or is the printhead "done"?

In most cases, Error Code 0x42 tied to printhead thermistor abnormality is not repairable at the printhead level. If the thermistor circuit is compromised (internal short/open), the printer will continue to protect itself and refuse operation. Practically speaking, that means the printhead is considered failed.

That said, there are a few limited checks that can sometimes confirm the situation (and in rare cases rule out a simpler cause):

1. Power down properly and let it dry thoroughly

   • Unplug the printer completely.

   • If moisture is present near the head cables/connectors, the printer may repeatedly fault as soon as it attempts a cleaning cycle.

   • Drying helps only if the issue is external moisture at the connector area-not internal head damage.

2. Inspect and reseat the printhead ribbon cables

   • A partially seated cable, crooked insertion, or damaged traces can cause abnormal sensor readings and communication faults.

   • Check for corrosion, ink, cleaner residue, or burn marks at the cable ends and connector sockets.

3. Check for obvious short-causing contamination

   • Any cleaner/ink residue bridging pins at the head connector can mimic a short.

   • If you see residue, cleaning the connector area with high-purity isopropyl alcohol and allowing it to fully dry may help-but only if the short is outside the sealed head body.

If you've already rechecked connections and the error repeats consistently, especially immediately during cleaning/flush attempts, then the diagnosis points back to printhead thermistor/thermal detection failure and the likely outcome is printhead replacement.

Do we have the L1800 printhead in stock?

For current availability, the best method is to search our site directly for the exact listing. Please go to BCH Technologies (https://bchtechnologies.com/) and search for "L1800 printhead". Inventory changes quickly, so the website will always be the most accurate source.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems, so 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 work on a first-come, first-served basis, and it can take a few weeks before we're able to accept your printer for drop-off. Our services are structured to repair either a whole printer or specific parts, with clear instructions on how to proceed. We also understand our rates aren't the most economical, so we strongly encourage self-help through online research. A great starting point is YouTube-especially our channel homepage at BCH Technologies on YouTube (https://youtube.com/@bchtechnologies). To find the most relevant videos, use the search icon next to "About" on the right-hand side of the menu bar. I receive dozens of questions daily asking if we have a video for a specific issue, and after creating videos for the past nine years, it's tough to remember every single one-so YouTube's search tool is the fastest approach. You may also get helpful recommendations from other channels that cover similar repairs.

Thanks again for reaching out and for supporting BCH Technologies. If you decide to replace the head, I hope the info above helps you avoid extra expense and points you to the most likely root cause-Error Code 0x42 (printhead thermistor abnormal temperature / X-Hot detection during flushing)-so you can make the next step with confidence.