LCD doesn't work, power supply is on, USB not detected from PC

[OniX]

Hi everybody,
I was attempting to repair my A20M printer (maybe a problem on thermistore, as suggested by Geeetech support).
Once i've assembled the hotend block i tried to "preheat PLA end" from lcd screen, suddenly the lcd screen has "turned off".
Now i can't control the printer neither from lcd nor from PC because with the usb cable isn't recognized at all (not a single beep form pc).
How i can solve this?

video explanation: https://www.youtube.com/watch?v=OWT2gm1UBNY

i've already disassembled board (gt2560) but i'm not sure what to check...

[William]

Hi, You can try
1. Reconnect the screen cable to try it out;

2. Check if there are three lights on the motherboard when the printer is turned on.
You can refer to this:

v3板正常情况.jpg (221.89 KiB) Viewed 6771 times

I hope this can help you.

[OniX]

only one light for me, the one 12 VB

the led on power supply is green.

I need another motherboard?

[William]

Hi, If only one light is on, it is not normal.
You can contact your sales to replace the motherboard.
I hope this can help you.

[OniX]

Problem solved by Geeetech support that sent to me a brand new gt2560. Thank you!

[William]

[Scubatron]

I went to post this exact same issue. While cleaning the hotend the system just stopped displaying anything but i could hear it on.

Taking it apart if find i have the exact same light on and hope to get a replacement gt2560 board from support thanks to your post!

[William]

Hi, If only one light is on your motherboard,
You may need to contact your sales to replace the motherboard.