I have an Ender 3 Pro which was the first purchase I ever made via Bang Good. At the time, I wasn’t entirely convinced that Bang Good was a legit business. The name and interface seemed too wild.

Bang Good is real, of course, and I was delighted the morning my printer arrived all the way from China in its neat little box.

I got it set up easily enough and immersed myself in the strange world of 3D printing.

After I’d filled a shelf with red plastic tidbits, my Ender 3 started misbehaving.

I’d power it on, the display would light up blue – but without any text on it.

I knew that all of the cables were in the right slots – I had already printed 30 strange plastic objects.

I double checked that the cables hadn’t fallen out. Everything looked fine.

After some time I figured out that I had accidentally removed the firmware.

If something goes wrong with the firmware, the printer doesn’t know how to tell you what has happened.

The main fan spins up as normal and the screen turns on, but doesn’t say anything on it.

This is an AI generated image, from the prompt “dead 3D printer”. There are so many details in this that I love.

How I accidentally removed the firmware

In the time before I had Octopi set up, I would download models from Thingiverse and manually ferry the files over to the printer on a micro SD.

I had a new model to print. I loaded an SD card into the printer and switched it on. Blank screen.

I switched it on and off a couple of times.

Still blank.

I figured I might have fried some internal component by moving the tray manually – did I force some little motor to spin at speeds wildly out of the expectations of the designers?

I had booted up the printer with the “wrong” SD card in it and that somehow had messed up the firmware.

The SD card that caused trouble for me was one that was loaded with Octopi.

The printer powered up and replaced it’s firmware with some other .bin file that it found on the SD card. It must have thought it was some fresh new firmware.

With the firmware gone, my Ender 3 forgot how to be a 3D printer and transformed into a strange desk ornament.

Look familiar?

I kept digging through forums until I got to the bottom of it.

At first I hadn’t considered that I’d flashed the firmware. I was under the impression that you needed an Arduino and a bunch of cables to do that. That was in fact the case with the original Ender.

However, since the arrival of the Ender V-2, both the Ender 3 and Ender 3 Pro models ship with a motherboard which can flash firmware via the SD slot.

This automatic flash feature must be very handy in the factory, but it should come with a warning sticker or something.

Every day, all over the world, people are switching their printers on and off, hoping the blue screen goes away.

It doesn’t go away.

Until now.

Easy fix for the blue screen of death

The fix is easy.

  • Download the Ender 3 Pro firmware
  • Put this .bin file onto the root level of an SD card.
  • Power off your Ender 3.
  • Insert the holy SD card that you just created.
  • Power up your Ender 3.
    • The screen will remain blank for a few seconds but then will boot up as normal.

The firmware that worked for me was this one:

Ender-3 Pro_4.2.2_Firmware_Marlin2.0.1 - V1.0.1.bin

I found that file in the Creality Google Drive folder here.

That’s it.

Your printer should be back to normal – assuming yours had the same problem as mine did.

Perhaps something more terrible has happened to your one.

This approach is unlikely to work for fire-damaged or submerged printers.

I hope that helped

It took some Googling to figure this out, so I thought I’d write it up and save someone some time. Let me know how you get on.

You can find me on Twitter and you can even buy me a coffee if you’d like.

Happy printing.