Mx 3140 display not working

[Maxx]

I had the same problem and it was the main board, you need to move the SD card and EPROM to the new board

Paper clip on adf board

[repn1999]

i second the dc power supply. these machines are terrible when it comes to the dc board blowing. I have probably changed out a couple dozen. i have had one be the sd card. if you try to put it in cn mode and it comes up it could be sd card. if the light just blinks with the fans on its the dc board.

[porky786]

I had the blank display issue, seems like the back light would shine slightly but nothing on the screen and nothing seen using a flash light. Also had solid green power led and optics seemed to boot up.

MY issue turned out to be Main PWB board.