If your Ender 3 Pro displays a blank screen when you switch it on, you may worry that you have a faulty printer.
Luckily, if you bought your Ender recently, it’s probably not that bad.
Maybe you accidentally flashed the firmware
I had a blank screen on my Ender 3 Pro. I eventually figured out that I had removed the firmware without realising.
If something goes wrong with the firmware, the printer know how to tell you what has happened. The main fan spins up as normal, and the screen turns on, but it’s blank.
In my case, I had already gotten a few successful prints out of the machine so I knew I hadn’t set anything up backwards. I checked that all of the cables were still plugged in. Everything felt fine.
How to temporarily brick your Ender 3
In the moments before I semi-bricked my Ender, I had a couple of micro SD cards out on the desk.
I picked up the wrong card, put it into the Ender 3 to load my next print, and switched it on. Blank screen.
I switched it on and off a couple of times.
What I figured out later was that I had just booted up the Ender with the wrong SD card in it. It happened to be one I had previously loaded with Octopi.
The printer powered up, found something on the SD that it thought was new firmware, and swapped it in.
Since I had no idea what was going on with this blue screen, I took to Google and binged on some obscure threads.
I was hoping I hadn’t inadvertently fried some component. Had I moved the tray too quickly and caused a voltage spike? How delicate are these things?
I kept digging through forum threads 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.
However, since the arrival of the Ender V-2, the Ender 3 and Ender 3 Pro models have started shipping with a new, 32-bit motherboard.
These newer motherboards can flash their firmware via SD, and this is something the original Ender 3 could not do. With the older models, you’ve have to break out the arduino and a couple of jumper wires.
This automatic flash feature must be very handy in the factory, but it could use a sticker or something. Every day, all over the world, people are switching their printers on and off to get the blue screen to go away.
It doesn’t go away.
Easy fix for the blue screen of death
The fix is easy.
Simply download the Ender 3 Pro firmware, put this .bin file onto the root level of an SD card.
Power off your Ender 3, insert this SD card, and then power it back up.
The screen will remain blank for a few seconds but then will boot up as normal.
The firmware that worked for me was the:
Ender-3 Pro_4.2.2_Firmware_Marlin2.0.1 - V1.0.1.bin
which I found here.
Your printer should be back to normal, assuming you had the same problem as I did.
Perhaps something much more terrible has happened. This approach is unlikely to work for fire-damaged, submerged or crushed 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. If you’d like, you could even buy me a coffee.