Help trying to save a very damaged Gameboy dmg

[lpoolm]

SO bought a few faulty consoles to keep me busy while on lock down.
Have a gameboy dmg. Was completely dead so opened up.
Has severe battery leakage. gave it a full strip and clean as best as I can.
it now turns on (red light) but no sound or anything on screen. I thought the front board was faulty but obviously a light shows its not dead!
Are there any things I could be checking, fuses on the front board or something else?
Thanks
added pictures of board cleaned:

 

[FAST6191]

Did the battery leakage come into contact with the board at all?

 

[micp]

SO bought a few faulty consoles to keep me busy while on lock down.
Have a gameboy dmg. Was completely dead so opened up.
Has severe battery leakage. gave it a full strip and clean as best as I can.
it now turns on (red light) but no sound or anything on screen. I thought the front board was faulty but obviously a light shows its not dead!
Are there any things I could be checking, fuses on the front board or something else?
Thanks

Have any of the caps gone bad on the board?
There's potential that the battery leakage as killed the board and sometimes no matter how much cleaning the things are just. too far gone.

Get some pictures up and I'll see if I can spot anything obvious.

 

[lpoolm]

Did the battery leakage come into contact with the board at all?

Yes, it was very bad! I am going to attach pictures now. This is it cleaned..

Have any of the caps gone bad on the board?
There's potential that the battery leakage as killed the board and sometimes no matter how much cleaning the things are just. too far gone.

Get some pictures up and I'll see if I can spot anything obvious.

Adding now

 

[gamesquest1]

usually it's good if you have a few spares to swap over, try a good front board on the unknown main board and the other way around, also look behind that shielding, some traces might've been eaten up by the leak

 

[JuanMena]

It's usual that the screen pins are un-soldered to the mother board. This is probably what's not giving you any picture on the screen.

So I would just grab my soldering iron to reheat the pins connecting the screen to the mother board in order to solder them back.
That's a usual fix.

To clean the battery leak, use Baking Soda + Rubbing Alcohol.

 

[lpoolm]

usually it's good if you have a few spares to swap over, try a good front board on the unknown main board and the other way around, also look behind that shielding, some traces might've been eaten up by the leak

I don't think I have a working front at the moment, unless I take apart my one, if I can find it..
I did think underneath the shielding might be bad too, will give that a go.

 

[JuanMena]

Maybe use a potentiometer to find dead traces, those traces will need to be connected with a small piece of cooper cable, you'll have to solder them manually.

 

[lpoolm]

It's usual that the screen pins are un-soldered to the mother board. This is probably what's not giving you any picture on the screen.

So I would just grab my soldering iron to reheat the pins connecting the screen to the mother board in order to solder them back.
That's a usual fix.

To clean the battery leak, use Baking Soda + Rubbing Alcohol.

Thanks will give that a go too

 

[FAST6191]

Where to start with that one?

The first picture looks really bad but if that is mostly ground plane on a double sided board (note I don't know if the GB is multilayered PCB) there should still be connection. I am slightly concerned at the E3 spring thing, and what that pad (supposed to be a via?) next to SP2 is. I don't like the look of some of those through hole components but that might just be light, and even if they are rusting a bit it looks like cosmetic right now.

Everything else though... clearly beyond economical repair but probably beyond "I am bored with unlimited time so for my own vanity" as well.
That bar across the ribbon looks like a dry joint, though if it is just mechanical then meh but if it is a jumper then maybe (looking at the other side I am leaning towards mechanical). The ribbon tracks themselves look damaged and continuing further to the right I would question that trace on the edge of the board (said trace going to the speaker as well). That through hole just to the left of the ribbon caught my eye but probably is good.

Between the DMG CPU B and the LH5264-TN diagonal from it first the pins on one side, and if that is bad I also would want to see the other. To say nothing of that via there as well. That capacitor to the left of the CPU also might have a slight case of the crusties but I don't know if that is blow out or general detritus.

The jack at the bottom is riddled with nastiness, and that is before you look at the underside.

The copper shield might have sacrificed itself (pun intended) but should still be making connection, though if it is a bus bar that is a different matter entirely. What is under that copper we need to know as well. I also don't like the solder joints at the top of that image next to the spring terminal (which could do with a cleaning too)

At very best this is a parts machine. Wall art if not.

 

[lpoolm]

Where to start with that one?

The first picture looks really bad but if that is mostly ground plane on a double sided board (note I don't know if the GB is multilayered PCB) there should still be connection. I am slightly concerned at the E3 spring thing, and what that pad (supposed to be a via?) next to SP2 is. I don't like the look of some of those through hole components but that might just be light, and even if they are rusting a bit it looks like cosmetic right now.

Everything else though... clearly beyond economical repair but probably beyond "I am bored with unlimited time so for my own vanity" as well.
That bar across the ribbon looks like a dry joint, though if it is just mechanical then meh but if it is a jumper then maybe (looking at the other side I am leaning towards mechanical). The ribbon tracks themselves look damaged and continuing further to the right I would question that trace on the edge of the board (said trace going to the speaker as well). That through hole just to the left of the ribbon caught my eye but probably is good.

Between the DMG CPU B and the LH5264-TN diagonal from it first the pins on one side, and if that is bad I also would want to see the other. To say nothing of that via there as well. That capacitor to the left of the CPU also might have a slight case of the crusties but I don't know if that is blow out or general detritus.

The jack at the bottom is riddled with nastiness, and that is before you look at the underside.

The copper shield might have sacrificed itself (pun intended) but should still be making connection, though if it is a bus bar that is a different matter entirely. What is under that copper we need to know as well. I also don't like the solder joints at the top of that image next to the spring terminal (which could do with a cleaning too)

At very best this is a parts machine. Wall art if not.

Thanks for the detailed reply!
I will go over a lot of the solder and reflow bits, will then look at checking some of the more specific things you mention and check traces.
I don't want to give up.. Yet.. I've got the time I just need to start go back to basics I suppose.
At least you have all given me some good ideas where to start!

--------------------- MERGED ---------------------------

Picture underneath heat sink, will give a little clean

 

[FAST6191]

After a clean would help.
Still one of those traces does not look great (next to what looks like a solder blob on the trace)
Several of those vias also don't look great but if it is just via stitching then eh. On the other hand several of the vias in the middle of the board might actually serve a purpose.
I don't know if that is stripped mask on the left or just a bit of remaining shield. Probably won't trouble things but I would note it in an assessment of a board anyway.

While note as nice an angle for it I am still worried about those pins next to the spring terminal as well, especially given what is right next do in the what looks like a stitched ground plane.

I am guessing that shiny solder on the right hand side is yours but it looks like it shorted out a couple of pins.
The wires on the bottom left look like dull joints but probably not dry. A trace running to the leftmost black one though does not look so hot.

 

[lpoolm]

After a clean would help.
Still one of those traces does not look great (next to what looks like a solder blob on the trace)
Several of those vias also don't look great but if it is just via stitching then eh. On the other hand several of the vias in the middle of the board might actually serve a purpose.
I don't know if that is stripped mask on the left or just a bit of remaining shield. Probably won't trouble things but I would note it in an assessment of a board anyway.

While note as nice an angle for it I am still worried about those pins next to the spring terminal as well, especially given what is right next do in the what looks like a stitched ground plane.

I am guessing that shiny solder on the right hand side is yours but it looks like it shorted out a couple of pins.
The wires on the bottom left look like dull joints but probably not dry. A trace running to the leftmost black one though does not look so hot.

thanks will work on these now.
quick question, the heat shield i have removed can i use copper tape as replacement or just put what i have taken off?

 

[FAST6191]

It is more likely to be noise reduction rather than heat shield on something like this (if the CPU does not have a heatsink then yeah, also this goes to a potentiometer case with the other points probably also being ground and is then more concerned with electrical connectivity than mechanical or heat coupling so there is that too).

If you can cut it into that shape then so it goes. Make sure to leave the holes in the relevant parts as those springs on the other side (others playing along then step 6 in https://www.instructables.com/id/Taking-apart-a-Nintendo-Gameboy/ ) might well have to make contact for actual reasons rather than just standoffs.

Be thankful it was there as well -- I just lined up the images of before and after and if it had gone through in the same locations as it attacked the shield... that would not be fun. Maybe the mask would have withstood it better than that copper but yeah.

 

[lpoolm]

We have life!!
No sound, might be the speaker or linked to the audio board, I do have a spare so might just swap that first as it looks a bit rough!

 

[JuanMena]

We have life!!
No sound, might be the speaker or linked to the audio board, I do have a spare so might just swap that first as it looks a bit rough!
View attachment 202967

Congrats! Just re solder the speaker to the cables to see if it's the speaker what's causing the problem.

On a second note, that screen has dead pixels. Reheating the soldering pins of the screen (the pins that are covered by a black strip on the back of the screen) should fix the problem.

 

[lpoolm]

Congrats! Just re solder the speaker to the cables to see if it's the speaker what's causing the problem.

On a second note, that screen has dead pixels. Reheating the soldering pins of the screen (the pins that are covered by a black strip on the back of the screen) should fix the problem.

yer i had a quick google, saw the lines down the screen could be fixed, that will be the next task..

 

[lpoolm]

Big thanks to everyone who has inputted today!
I now have sound!
A quick refresh I went over a lot of the pins mentioned and gave a little reflow with fresh solder, gave it a few more cleans.
Replaced the audio board with a spare and sound began working so must have needed a lot of work to get that going!
Tomorrow I will attempt to fix the vertical lines and give the console a big deep clean, all needs washing!
The front half is a little yellow (not major) but might retrobright it while we have some sun!
I will look to make a video to put on my youtube channel.

 

[gamesquest1]

yeah I have found the heat along the strip technique usually leads to the lines coming back not too long later, can sometimes last a few months but I think it does just naturally start to split again, might be worth just replacing the whole screen with a new LCD/IPS display, with the IPS displays you get the whole front board replaced too so you wouldn't have to worry about cleaning that part up either

 

[lpoolm]

Right so I have fixed my lines down the screen, retrobriting the console, all good... No!
Decided to put a game in, does not load? Just shows a black box, like when you turn on without a game in.
A few of the solder joints on the cart looked a bit rough, most took fresh solder but a few at the end wouldn't so got my heat gun out and removed from the board, cleaned all pins and contacts put back on, soldered, tried a game, still not working?
Got my multimeter out and checked each pin to its test point, all beep? (in pic below).
So could it be one of the chips on the board? looked close and they have there names next to them so is it worth swapping the DMG Cpu, or any other ideas what it could be?
I really thought I was nearly there!