I’ve repaired my filament sensor today. After I’ve finished checking every connections, I turned on my A1. Everything was good and I powered it off. When about 5 minutes later I returned it on the screen, the fans and basically everything except the power switch’s light just won’t turn on
If you have tried turning off for a few 10s of seconds then turning back on and it does the same then definitely sounds like an issue for Bambu support. Check that the mains cable is fully pushed in, as are any of the connections you touched internally, just in case it is some silly intermittent power thing.
Double check the cables, switch, and if all else fails, contact BL.
Just to give a hope to you all who will ever read this: do not panic, fix might be 3mins away 
My A1 was bricked - I thought. Powered off, on, off 20x. Power button got on, front LED got on, but display black, camera’s LED off, no boot up sound.
I got it upside down, re-connected all the connectors back, powered on - the same.
Was already gathering documentation for my first-ever support ticket…
Then I looked up on SD card. Powered off. Pushed SD card out, powered on.
Tadaammmm! Display alive, camera LED ON, welcome sound. SD card was an issue. When got it to my laptop, card was unreadable also there. Formatted new SD card, all works fine.
Stay calm and print more Good luck!
Thank you so much, man. I never would have found it. It definitely works.
Hi everyone,
I’m having a serious issue with my nearly new Bamboo A1. When I turn it on, the power button light comes on, but the display stays completely off, and the front LED near the SD card (HMN or HMI light) doesn’t light up at all. It’s like the printer isn’t booting.
Here’s what I’ve already tried:
- Verified all cables are fully connected (multiple times)
- Removed the SD card and powered on – no change
- Fully unplugged the printer for several minutes and tried again – no change
- Tried powering on with and without accessories connected
The unit is almost brand new, so this is extremely disappointing. I’m open to suggestions if anyone has a fix I haven’t tried.
If anyone has had this issue or knows what Bamboo Lab’s support response time is like, I’d appreciate any advice.
If your Bambu Lab A1 doesn’t work but shows the power light and you’ve already tried checking the cables, checking the electrical current, checking the SD memory, maybe it’s the toolhead. I was having problems with my A1 and decided to try all these solutions and when it didn’t work, I tried checking the collections with it on, and I realized that it only stopped working when I connected the toolhead, so now I’m going to replace it.
Did you ever get this resolved? I am having the same issue. Mine is only 1 month old. Just quit working. Stopped mid plate at beginning of print. Rear power light is on and nothing else, screem AMS nothing is working. Wont power back on. I have all the things you have and the fuse. ALl is fine. 
submitted a ticket and hoping it dont take weeks for a reply.
same issue. what next??? bought Bambu every one said best printer out there. I have printers I have had for years other than belts and maintenance no issues. What else can I try?
I got the same issue. Did anyone find a fix to this?
I printed a few parts, came back after a day, took them off, cleaned the plate and sent another print. It failed to connect to the printer so I thought ill reconnect it to the WIFI but the screen was off. I turn off and back on, nothing happened expect light on the power buttons. Checked and tried everything but no response from the printer.
have you replaced your tool head if so did it resolve the issue?
you are the best!!! after I removed the SD card and powered the printer back on it took maybe 10 seconds and the screen started working again 
thank you SO much!!
Tengo el mismo problema. ya probe todo lo que recomiendan de sacar la tarjeta y revisar todos los cables pero sigue igual. solo prende la luz de encendido trasera.
my Bambu A1 mini is just 2 days old and is will not turn on I tried all the tricks even the SD card and it still is not working so I am open to suggestions
Ello,
You are in quite the sticky situation, but never fear, we’re here! (I know that was very cringe yes.)
Anyways..
Is it your SD Card? As I also said here, your SD Card might be corrupted, which could cause the printer to not turn on fully.
It also could be your toolhead, as it can short out through a USB-C Cable losing contact, which could also be the issue.
I’ve attached some links below for you,
https://www.reddit.com/r/BambuLabA1/comments/1jouja2
Cheers, 
I had the same issue. Mine sat for several weeks. I just tried to turn it on and the same issues as above. I pulled the SD card out and it booted up and put the card back in.
I’ve had my A1 mini for only a week now and it suddenly won’t power in. I’ve removed the SD card and put it back in several times now and it still won’t work. I don’t know what to do because Bambu hasn’t responded to me yet and it’s extremely difficult to try and return it. If anyone could provide me with some guidance, I’d greatly appreciate it. TYIA
Thank you Thank you Thank you!! This did the trick!!
I had the same issue and it ended up being a burnt NTC thermistor.
Want to avoid this in the future? The sd card stores images taken during printing, filling up the card. If the card becomes too full, it requires reformatting which deletes everything, including your gcodes. Avoid by deleting the images & other, overstuffed folder(s) files from the card. Also suggest turning off the camera in the printer’s settings, and eliminating the need to clean the card folder(s). Backing up any gcode files is a good idea, too.