3-in-1 Combo B12, F1 & F2 Fuse for Epson ET-8550 / ET8550 / ET-8500 – Fix Errors 031004, 031005, 031006, No Power, Freeze

This repair bundle includes the key on-board protection components for the Epson ET-8550, ET-8500, and ET8550 series. These components commonly fail when the printhead or cable shorts, leading to startup failures and system errors.

This kit includes all three parts:
F1 Fuse (individually labeled)
F2 Fuse (individually labeled)
B12 (individually labeled)

Each part comes in its own clearly marked anti-static bag.
Do not use the F1 and F2 fuses interchangeably-they may look identical, but they serve different circuits and must be installed in the correct locations.

Common Symptoms This Bundle Addresses

These components often fail when there is an electrical short, which can cause:
Errors 031004, 031005, 031006
Printer powers on but freezes during startup
Printer turns on for a moment, then shuts off
Completely no power or partial power
Blank printing (printhead receives data but not firing power)
Startup stops halfway, then throws an error
Printer detects the printhead inconsistently
These symptoms typically mean that one or more protection components (F1, F2, or B12) have opened or failed.

Important Note
Replacing these parts does not guarantee a full repair.
They usually fail because something upstream was damaged-commonly:
A shorted printhead
A burnt FFC cable
A failing driver circuit
Installing new components without correcting the root cause can cause the new parts to fail again.
This bundle is intended to help trained technicians restore the correct power pathway, but it is not a guaranteed fix for every case.

Package Includes
1 × F1 Fuse (in labeled anti-static bag)
1 × F2 Fuse (in labeled anti-static bag)
1 × B12 (in labeled anti-static bag)

All components are tiny SMD parts and require micro-soldering skills.
If you are not experienced with precision soldering, please seek help from a local technician or search "Makers around me" to find nearby makerspaces or hobbyists skilled in electronics repair.