Backlight but no display. Dock is working

Nintendo Questions Nintendo Switch
1

Hi, I’m happy to have found this forum!
Hope my English is good, I’m french.

So, I replaced P13USB because switch did not powers on.
Unfortunately, while reinstalling the board, I broke some pins of the LCD connector.
So I ordered a new one and replaced it, but didn’t know what I did, I managed to solder it misaligned,I mean, top left pin of the LCD pad of the board was soldered to pin 2 of the connector, etc.
I shifted it 1 pin to the left.
I saw that too late. I started the console. No display.

When I saw my error, I desoldered it, and resoldered at the good place.

But no change, console is working, but only on dock.
I see backlight is working, touch and sound is working.
But screen stays black.
I checked everything single pin of the connector, it is properly soldered and not moving.

Any help appreciated.

2

I would check with another unit if the display is ok and check the circuit left of the lcd connector and the four chokes underneath the connector. (values are in mV and meassured in diode mode)

Display_connector
Display_connector1387×683 42.9 KB

3

Thanks for your help I really appreciate.

I found this diagram some days ago and tested everything, all values are pretty similar. But I will check again tomorrow.
There is no chokes underneath the LCD connector, there is no short in diode mode at these points.

8613 is seems good, I have 5v, -5v, 3.6v and enable pin is working.

I’ll see if I can test this board with the screen of my son’s switch but I don’t want to damage it.

Would you think it’s better to test this motherboard with another working screen, or the possibly damaged screen on a working motherboard?

And, is there some circuitry inside the screen, if I disassemble it, to see if there is some damage, or short?

Thanks again!

4

Idk. If the readings on the mainboard are ok, I would try another working screen.

5

So I tried this motherboard with a good screen and I always have backlight but no picture.

I checked again all values of the previous diagram and everything is good, I also checked directly inside the LCD connector to be sure.

6

Edit: oh I’ve just seen I have flickering screen!
Pressing almost everywhere does not changes flickering behavior.

7

Ok. Maybe the soldering at the lcd connector needs some rework. I would check the pins and in case more then one is loose, reheat and reflow the whole connector from the backside.

8

So I cleaned the connector again and again, and it seems to work now, there was a lot a flux inside as I soldered it twice, I didn’t thought it could cause this.

Thanks, again, for your help!

9

Nice to hear.
Flux is your best friend while soldering, but shouldn’t get in the zone where the contacts are touching. :grin: