Will Replacing the Epson WorkForce WF-3640 or WF-3620 Motherboard Restore Aftermarket Cartridge Compatibility After a Firmware Update?

Question:
I updated the firmware on my Epson WorkForce WF-3640 / WF-3620, and after that the printer stopped accepting aftermarket cartridges. Now it feels like the machine has become a paperweight. If I replace the motherboard, will third-party cartridges work again?

Answer:

The short answer is: maybe, but not always.

In many Epson printers, including the WorkForce WF-3640 and WF-3620, firmware updates can change how the printer communicates with cartridges. Epson updates sometimes tighten chip authentication, which means cartridges that worked perfectly before the update may suddenly be rejected afterward. That is why many users feel the printer was effectively disabled after a firmware change.

Replacing the motherboard, also called the main formatter board, can sometimes restore compatibility with aftermarket cartridges, but only under certain conditions. The reason is that the motherboard stores and controls the printer's firmware behavior. If you install a replacement board that has an older firmware version-one from before Epson introduced stricter cartridge validation-then the printer may once again accept compatible third-party cartridges. However, if the replacement board has the same updated firmware or another equally restrictive version, then changing the board will not solve the problem.

So the real issue is not just the board itself. The key question is: what firmware version is on that replacement board?

Here are the main possibilities:

1. Older motherboard with older firmware:
   This is the best-case scenario. If the board came from a donor machine or old stock and still carries pre-update firmware, your aftermarket cartridges may work again.

2. Replacement board with current firmware:
   In this case, the printer will likely behave exactly the same as it does now, and the aftermarket cartridges may still be rejected.

3. Board swap creates additional setup issues:
   Even if the board is compatible, replacing it is not always plug-and-play. Some models require matching components, initialization, or recalibration. In some cases, the printer may boot but present new errors or fail to recognize certain assemblies correctly.

When firmware blocks aftermarket cartridges, users commonly see cartridge-related messages such as "cartridge not recognized," "cannot recognize ink cartridge," "replace cartridge," or similar chip/authentication errors on the display. These are not always given as traditional numeric error codes, but they are still firmware-triggered cartridge recognition errors. If your printer is also showing specific Epson error codes after the board change or during startup, those codes would need to be interpreted separately, because they may point to a board installation issue, scanner initialization issue, carriage problem, or another hardware fault unrelated to the cartridges themselves.

A few practical points may help:

• If your only goal is to restore use of third-party cartridges, replacing the board is a possible workaround, not a guaranteed fix.

• Buying a replacement motherboard without knowing its firmware version is a gamble.

• A used board pulled from an older machine may offer better odds than a newly sourced board that was updated later.

• If the printer was working fine before the firmware update except for the cartridge lockout, then the firmware is the most likely cause rather than a separate hardware failure.

• This is one reason many technicians strongly recommend never updating firmware unless there is a specific reason to do so.

There is also another layer to this: some aftermarket cartridge brands update their chips over time to match newer Epson firmware requirements. So before replacing a motherboard, it may also be worth checking whether a newer chip version of the compatible cartridge exists for your printer model. Sometimes the problem is not that all third-party cartridges are blocked forever, but that the older chip generation is no longer accepted by the updated firmware.

If you do replace the motherboard, I would suggest paying attention to the following:

• Confirm that the board is specifically for the WF-3640 / WF-3620 family.

• Ask the seller whether they know the firmware generation on the board.

• Inspect all ribbon cables and connectors carefully during installation, because a slightly misseated cable can create completely different faults.

• After installation, test with both an aftermarket cartridge and, if available, one known-good OEM Epson cartridge to separate a firmware issue from a board or carriage communication problem.

Printer problems like this are often difficult because they are hands-on by nature. Because of that, we are not able to provide remote troubleshooting, repair suggestions, or step-by-step support for printer repair work. We do offer an in-person evaluation and repair option through our local diagnostic and repair service [https://bchtechnologies.com/printer-repair-service]. Due to heavy demand, we handle repairs on a first-come, first-served basis, and it may take several weeks before we are able to receive your printer for drop-off. We can service either a complete printer or specific parts, with instructions provided for each option. That said, we understand our pricing may not be the lowest available, so we strongly encourage self-help research first. A great place to start is YouTube, including our BCH Technologies YouTube channel [https://youtube.com/@bchtechnologies]. On the channel homepage, you can use the search icon next to "About" on the right side of the menu bar to look for videos on your exact topic. We receive many questions every day asking whether we have covered a certain repair before, and after years of publishing videos, the fastest method is usually to search directly on YouTube. It may also show useful videos from other creators that can help.

Thank you again for reaching out and for your support. We truly appreciate your engagement, and we hope this gives you a clearer idea of what a motherboard replacement can and cannot do in a firmware-lock situation.