Graphical issue on display

Hi, I am trying to fix a switch with emmc issue but to confirm everything else works ok, I boot into RCM and with injecting heckate I get no backlight or display but if I inject atmosphere I get the below image… any ideas why? its the same with another screen and with and without the emmc module

Try injecting the Biskeydump payload and take a photo to show :+1:

Hi severence, I get the below

Hey,

If you remove the shield over the SoC/Ram, I use a blade in the latches and twist to remove, after load that Biskeydump payload again and put slight downward pressure on the ram modules and see if those graphical artifacts change, if they do then it’s likely a connection issue with the ram and a reflow may resolve :slight_smile:

Thank you, it does make a difference so will give it a go.

Fingers crossed :crossed_fingers:

Hi Severence, been busy with work and decorating but I did try reflow last night and that didn’t help, I took it off and used a mask to add new solder paste to reball it and its still the same when back on. The board is slightly bent so not sure if all balls are making a connection or not.

Could the ram chip itself be bad and need replacing or is it more likely the pads are not making a good connection?

Thanks

Hey man,

Same graphical artificating?

I’d verify that putting slight pressure on the SoC while Biskeydump is loaded up that that doesn’t also change/resolve the graphical aritifacts too, as it may be a possible SoC issue or joint problem if it does

They very rarely fail and the most common faults surrounding them is joint issues. I’ve started using preformed 0.35mm balls using the “corner ball method” for Switch ram as solder paste always results in undersized and sometimes possibly uneven balls which is a problem if the board has any significant warping. Example here, though you want to practice this technique on some scrap ICs first to get a feel for it.

Thanks for the tips, CPU doesn’t seem to make a difference which should be a good sign i suppose.

Ordered some 0.35 balls last night and will have another go when they arrive, see if it makes a difference and report back then