My yamaha DM1000 mixer starts firmiware and only lights a blue screen.

Hi! I have a mixer dm1000 yamaha that started to no longer start the firmiare, instead is the display screen only with the backlight lit. All functions are off.

I have knowledge in electronics and do the maintenance of my consoles but this dm 1000 did not do any previous maintenance. can someone with experience in this situation guide me ????

thank you!