Crazy scan lines on my screen

[Henryk_FS]

I dont know how to describe this problem in detail. Those black lines have been going crazy on my screen since yesterday. I posted this issue on reddit but no one has answered it yet.
What strange is that when i open FBI, other non 3d supported software or increase the screen brightness, those black lines vanish.
A video of this problem is here :
Im so lost right now, guys. Please help me (

 

[Sono]

I have never seen this before, this is weird.

To me this looks like the display itself is fine, but the power regulator generating the correct voltages to drive the display panel itself is somehow collapsing when not under heavy load.

Can you boot GM9 and change the brightness there to see if it happens?

 

[Henryk_FS]

Thank for your responding! The screen looks completely normal in GM9 even if i reduce the screen's brightness to the lowest. No sign of any error ._.

I have never seen this before, this is weird.

To me this looks like the display itself is fine, but the power regulator generating the correct voltages to drive the display panel itself is somehow collapsing when not under heavy load.

Can you boot GM9 and change the brightness there to see if it happens?

 

[Sono]

Thank for your responding! The screen looks completely normal in GM9 even if i reduce the screen's brightness to the lowest. No sign of any error ._.

That's good to know.

Considering that based on the video 3D mode seems to work perfectly, I think this is really an issue with the power supply used to generate the panel voltage to drive the display.

Spoiler: Technical garbage

I have absolutely no idea why the lines are random instead of organized, but to me this looks like there is a problem generating the positive and negative voltage required to drive the liquid crystals, and it seems to fail driving those voltages during Vcom* flicker.
I would check near the PMIC area for a broken transistor, shorted/cracked capacitor (those yellow rectangle ones), or the PMIC chip itself. Very unlikely, but I would also check a different battery just in case, but I kind of doubt that.

* Vcom flicker explained shortly: if you just drive the display with a fix positive and negative voltage, then it will burn in, so basically every LCD controller will adjust some LCD driving voltage from every second, every scanline, every pixel, or all of the above.
In the case of the 3DS, there is a checkerboard pattern (barely visible unless you have a really abused display, like mine is), and there is the scanline pattern (which you're seeing).
Considering that it doesn't happen in GM9 at all makes me think that this could be indeed a broken transistor, capacitor, or PMIC chip itself, and the display panel itself is completely fine, and should not be replaced.

If you don't have a repair shop, can't afford to fix it, and/or can't attempt to repair it yourself, I would just keep it on high brightness to minimize the problems, although I'm not sure how long it would last before it would get the infamous "3DS Power LED comes on and turns off instantly with a loud pop sound" problem.

I would try a different battery. Very unlikely that the battery is the problem, but it should not hurt to try. You will have to set a new time though, and Animal Crossing will complain that you have edited the time, but other than that it's completely risk-free to try replacing the battery, if you have an another 3DS with a compatible battery.

 

[Henryk_FS]

That's good to know.

Considering that based on the video 3D mode seems to work perfectly, I think this is really an issue with the power supply used to generate the panel voltage to drive the display.

Spoiler: Technical garbage

I have absolutely no idea why the lines are random instead of organized, but to me this looks like there is a problem generating the positive and negative voltage required to drive the liquid crystals, and it seems to fail driving those voltages during Vcom* flicker.
I would check near the PMIC area for a broken transistor, shorted/cracked capacitor (those yellow rectangle ones), or the PMIC chip itself. Very unlikely, but I would also check a different battery just in case, but I kind of doubt that.

* Vcom flicker explained shortly: if you just drive the display with a fix positive and negative voltage, then it will burn in, so basically every LCD controller will adjust some LCD driving voltage from every second, every scanline, every pixel, or all of the above.
In the case of the 3DS, there is a checkerboard pattern (barely visible unless you have a really abused display, like mine is), and there is the scanline pattern (which you're seeing).
Considering that it doesn't happen in GM9 at all makes me think that this could be indeed a broken transistor, capacitor, or PMIC chip itself, and the display panel itself is completely fine, and should not be replaced.

If you don't have a repair shop, can't afford to fix it, and/or can't attempt to repair it yourself, I would just keep it on high brightness to minimize the problems, although I'm not sure how long it would last before it would get the infamous "3DS Power LED comes on and turns off instantly with a loud pop sound" problem.

I would try a different battery. Very unlikely that the battery is the problem, but it should not hurt to try. You will have to set a new time though, and Animal Crossing will complain that you have edited the time, but other than that it's completely risk-free to try replacing the battery, if you have an another 3DS with a compatible bba

That's good to know.

Considering that based on the video 3D mode seems to work perfectly, I think this is really an issue with the power supply used to generate the panel voltage to drive the display.

Spoiler: Technical garbage

I have absolutely no idea why the lines are random instead of organized, but to me this looks like there is a problem generating the positive and negative voltage required to drive the liquid crystals, and it seems to fail driving those voltages during Vcom* flicker.
I would check near the PMIC area for a broken transistor, shorted/cracked capacitor (those yellow rectangle ones), or the PMIC chip itself. Very unlikely, but I would also check a different battery just in case, but I kind of doubt that.

* Vcom flicker explained shortly: if you just drive the display with a fix positive and negative voltage, then it will burn in, so basically every LCD controller will adjust some LCD driving voltage from every second, every scanline, every pixel, or all of the above.
In the case of the 3DS, there is a checkerboard pattern (barely visible unless you have a really abused display, like mine is), and there is the scanline pattern (which you're seeing).
Considering that it doesn't happen in GM9 at all makes me think that this could be indeed a broken transistor, capacitor, or PMIC chip itself, and the display panel itself is completely fine, and should not be replaced.

If you don't have a repair shop, can't afford to fix it, and/or can't attempt to repair it yourself, I would just keep it on high brightness to minimize the problems, although I'm not sure how long it would last before it would get the infamous "3DS Power LED comes on and turns off instantly with a loud pop sound" problem.

I would try a different battery. Very unlikely that the battery is the problem, but it should not hurt to try. You will have to set a new time though, and Animal Crossing will complain that you have edited the time, but other than that it's completely risk-free to try replacing the battery, if you have an another 3DS with a compatible battery.

Thank you very much! I'll try to replace the battery, but I don't have one now. I think I'll try to attempt a fix first. Where should I start?

 

[Sono]

Thank you very much! I'll try to replace the battery, but I don't have one now. I think I'll try to attempt a fix first. Where should I start?

You can try an used battery as well. It just needs to be a different battery temporarily, to know if it's caused by the battery or not.

If you can't get a battery for free to try, then don't bother, because it's very unlikely that it's caused the battery. It's just that if you have another battery which you don't need to pay for, you could test your luck if it's caused by the battery (very unlikely, but possible) or not.

 

[Henryk_FS]

You can try an used battery as well. It just needs to be a different battery temporarily, to know if it's caused by the battery or not.

If you can't get a battery for free to try, then don't bother, because it's very unlikely that it's caused the battery. It's just that if you have another battery which you don't need to pay for, you could test your luck if it's caused by the battery (very unlikely, but possible) or not.

It seems like the battery isn't the problem because I've tried it with my DSI's battery and the screen is still like that. I found that in the video player for the 3DS, the problem only appears when I choose 3D or 800 px mode in the LCD setting. The screen even gets colorwashed in 800 px mode. Now, I think the problem is with the ribbon cable, or maybe even the software after I updated the system. I'm still looking for a solution, and none of their problems resemble mine lol.

 

[elk1007]

It seems like the battery isn't the problem because I've tried it with my DSI's battery and the screen is still like that. I found that in the video player for the 3DS, the problem only appears when I choose 3D or 800 px mode in the LCD setting. The screen even gets colorwashed in 800 px mode. Now, I think the problem is with the ribbon cable, or maybe even the software after I updated the system. I'm still looking for a solution, and none of their problems resemble mine lol.

I suspect the ribbon cable as well.
You can get a cheap panel on ebay for about $20-$30.
I did want to inquire, have you tried slapping the console?

Jarring it might wiggle the loose cable and provide some troubleshooting feedback.

 

[Sono]

Oops, I have completely forgot about the ribbon cable.

Do you have a GBA game installed onto the system? I could send an LCD test program, but it runs in "GBA mode" on the 3DS. The test could shed a light if it's indeed a ribbon problem or not.

But yeah, a physical test is also advisable. Folding the screen back and forth slowly should reveal if it's a ribbon problem if the folding influences the way the lines appear.

 

[Henryk_FS]

Oops, I have completely forgot about the ribbon cable.

Do you have a GBA game installed onto the system? I could send an LCD test program, but it runs in "GBA mode" on the 3DS. The test could shed a light if it's indeed a ribbon problem or not.

But yeah, a physical test is also advisable. Folding the screen back and forth slowly should reveal if it's a ribbon problem if the folding influences the way the lines appear.

I tried gba game and the screen works fine. I tried to fold the screen too, but the screen still behaves like that at any angles. If you have any LCD test software or homebrew, I'd like to test it.

Post automatically merged: Dec 5, 2022

I suspect the ribbon cable as well.
You can get a cheap panel on ebay for about $20-$30.
I did want to inquire, have you tried slapping the console?

Jarring it might wiggle the loose cable and provide some troubleshooting feedbackThank you for responding! I tapped it not slapped it because I was afraid I would make the problem worse, and it didn't help. I'd like to replace my ribbon cable to test it out but unfortunately, eBay is not a service in Vietnam thus the shipping will be very expensive. I tried finding the 3DS's part on an online shop called Shop

I suspect the ribbon cable as well.
You can get a cheap panel on ebay for about $20-$30.
I did want to inquire, have you tried slapping the console?

Jarring it might wiggle the loose cable and provide some troubleshooting feedback.

Thank you for responding! I tapped it not slapped it because I was afraid I would make the problem worse, and it didn't help. I'd like to replace my ribbon cable to test it out but unfortunately, eBay is not a service in Vietnam thus the shipping will be very expensive. I tried finding the 3DS's part on an online shop called Shopee but couldn't find what I needed at all.

Post automatically merged: Dec 6, 2022

I think the screen is confusing between 3d and 2d mode because in 1-3 screen brightness i see pixel become dots on the screen ( looks like when slide 3d up ). When increase brightness they turn into horizontal pixel rows. Do anyone think the problem is come from the 3d slider ?.

 

[Sono]

I have thought about this issue more, and I think this might be a problem with the parallax barrier (responsible for 3D effect by blocking light certain ways).

As for why brightness would affect how absurd this effect goes, I think it's simply just the backlight PWM (tl;dr: low backlight flickers, as it's cheaper and more power-effective than flicker-free backlight dimming), and the parallax barrier probably picks up this signal due to being near to the parallax barrier circuitry.

Does 3D mode even work at all? If so, what do you see at lower brightness (where the issue occurs) ? Try setting it to the lowest possible brightness, as 3D mode doubles the brightness, which would make this issue go away.

 

[Sono]

I have thought about this issue even more, and it's most likely a damaged flex cable (parallax barrier signal gets come crosstalk from other signals due to not being connected properly (floating)), or possibly a damaged display panel (the parallax barrier is also a display).

Either way, you need a screen replacement. Although clean the connector first, as I have a DS Lite which had the connector go bad!

As to reply to my own question, with 3D *support* enabled, you'll get this problem, as the parallax barrier gets initiailzed. It doesn't happen in GodMode9, as it doesn't initialize the parallax barrier, because it"s 2D only.