Maimai Finale Left Screen

[keenanty01]

Hi all!

Sorry this is my first time posting in this forum, hope im posting in the right area

I recently bought a maimai finale machine which I set up yesterday. After setting up the machine both screens worked perfectly for around 15 minutes, after that the left screen stop displaying maimai. We tried disconnecting and reconnecting the VGA cable, to which the screen flickers on for around 3 seconds then flicks back off.

Probably not the best photo, but let me know if you need photos of cables/anything else to help troubleshoot.

 

[nem]

The backlight has probably gone out. The game wouldn't boot otherwise. If you shine a flashlight towards the screen, you can see the game playing. It's a common issue with maimai.

Basically there's a row of leds on two strips. 64 leds on one strip, strips on both sides of the monitor. These are what illuminate the LCD. If one of the LEDs fails on either strip, the whole backlight (all 128 leds) turn off.

You can actually test this by accessing the OSD with the remote (use the flashlight on the screen) and turning down Brightness to 0. Then turn off the display and turn it back on. The monitor should now boot into a low power, fail state mode and all of the working leds will shine very faintly. The leds are connected in series, 16 leds each. There's likely going to be a segment that's out. Somewhere there is your broken led.

Anyway, you could replace the one faulty led, but probably just easier to do the whole strip. Strips are sold in pairs, so you would be replacing the complete backlight.

It's a bit of a PITA to take apart the LCD, but perfectly doable. A complete disassembly with pictures is here:

https://twitter.com/sugoipelihalli/status/1414568952227844098

The LED strips I got were 420TA26V1. I bought the 20 dollar ones from Aliexpress.

 

[keenanty01]

The backlight has probably gone out. The game wouldn't boot otherwise. If you shine a flashlight towards the screen, you can see the game playing. It's a common issue with maimai. Basically there's a row of leds on two strips. 64 leds on one strip, strips on both sides of the monitor. These are what illuminate the LCD. If one of the LEDs fails on either strip, the whole backlight (all 128 leds) turn off. You can actually test this by accessing the OSD with the remote (use the flashlight on the screen) and turning down Brightness to 0. Then turn off the display and turn it back on. The monitor should now boot into a low power, fail state mode and all of the working leds will shine very faintly. The leds are connected in series, 16 leds each. There's likely going to be a segment that's out. Somewhere there is your broken led. Anyway, you could replace the one faulty led, but probably just easier to do the whole strip. Strips are sold in pairs, so you would be replacing the complete backlight. It's a bit of a PITA to take apart the LCD, but perfectly doable. A complete disassembly with pictures is here: https://twitter.com/sugoipelihalli/status/1414568952227844098 The LED strips I got were 420TA26V1. I bought the 20 dollar ones from Aliexpress.

Thanks so much for the reply man. I'm wondering if it is the same issue though as the screen flickers on and off. I've recorded a video if you're able to take a look

View: https://youtu.be/0IS3bh7Qs88?si=CraKT5BoSN6uaKpW


Appreciate the reply again - let me know if you need any photos of anything

 

[nem]

That's the backlight going out. Take out a flashlight and you'll see.

 

[keenanty01]

That's the backlight going out. Take out a flashlight and you'll see.

Hi Nem!! Sorry to open up this post after such a long time of it being silent. I wasn’t able to fix the screen with the mentioned parts, but only recently found out I was purchasing the wrong part for my screen! I was needing to purchase a P420HVN02.1! Since then I’ve finally managed to get both screens working!

The issue now is that I can’t seem to get it of 0 brightness. I put it back up to 50% but it seems to go back to 0 everytime I restart the machine. Is there anyway I can fix this to keep it on 50% upon reboot?

Thanks!!!

 

[nem]

That's annoying. I haven't had that issue. There's some memory on the driver board that holds those settings. It's probably part of an IC package.

Have you tried resetting to factory defaults?

If that doesn't help, I think you might have to start asking if anyone has a wrecked monitor that could sell you the driver board.