A 22 IDEX that will not start usually points to either (1) an open (blown) fuse preventing mains power from reaching the electronics, or (2) a corrupted micro‑SD card that holds the firmware and file system the controller needs to boot.
This guide walks you through diagnosing both scenarios, replacing or resetting what’s needed, and getting the printer back online.
Purpose |
Item |
Electrical checks |
Multimeter with continuity/beep mode |
Fuse replacement |
15A fuses (×2) |
SD‑card work |
Micro‑SD card reader & computer with Internet access |
Firmware |
Download links provided below |
Misc. |
Needle‑nose pliers or fuse puller, anti‑static wrist strap (recommended) |
⚠️ Safety
Always disconnect mains power and wait at least 60 seconds before opening the electronics bay. Capacitors can hold charge briefly after unplugging.
¶ Step 1 — Check the Main Fuses

- Unplug the printer from the wall.
- Locate the two fuses on the mainboard (Figure 1).
- Test each fuse
- Continuity test: Place multimeter probes on both ends. A continuous beep = good; silence = open.
- Visual check (backup method): Remove the fuse and inspect the filament wire for breaks or dark spots.
- Replace any blown fuse with an identical 15A.
- Re‑apply power and try to start the printer.
- If it powers on now, you’re done.
- If it still stays dark, continue to Step 2.
If you eject the printer’s micro‑SD card and on the micro‑SD card see no files or only random characters, the file system is corrupted and the controller cannot boot.
- Insert the SD card into your computer.
- Copy any visible files/folders to a safe location.
💡 Tip — Create a backup folder!
- Open your OS’s formatting tool.
- Select FAT32.
Each link contains the full SD‑card file tree including the required system folders:
V3 Newer — shipped after Nov 2024
V3 Older — shipped before Nov 2024
V2 (Newer/Upgraded) (4 endstops)
V2 (Standard) (2 endstops)
V1
- Click the green “Code” → “Download ZIP” button on the correct branch.
- Extract the ZIP.
- Copy all extracted folders (including
user
) to the freshly formatted SD card. (sys, filaments, user, macros, gcodes, firmware, www)
- Safely eject the SD card from the computer.
- Insert it into the printer’s SD slot.
- Plug in the printer.
- Reboot & Access‑Point mode:
- After reinserting the card, the printer restarts in the factory configuration.
- Because no network is configured yet, it boots into Wi‑Fi Access‑Point mode broadcasting an SSID named
22IDEX
.
- Connect to that network from your computer or phone to open the web UI.
- Configure networking — follow the wiki section on Network Modes (V3) to join your local Wi‑Fi or Ethernet.
- Z‑Probe pickup angle & position — see Z‑Probe Calibration.
- Run Auto‑Calibration — launch the routine described in Auto‑Calibration (V3).
¶ 2.7 Flash Mainboard Firmware
In the web UI console, send: M997 S0
- The printer erases and flashes the firmware in the mainboard’s MCU.
- It reboots automatically when the update completes.