Game Boy Game Repair?

Dear fellow Gamers,

I have two copies of Pokemon Yellow where the Rom has been corrupted... One has Sprites that appear exclusively as Black Boxes and the other one is also damaged in a similar way.
Is it possible to repair these games? They have been gathering dust in my room, and I thought it was sad that they may never be played again... Any thoughts?

Thanks,

Noah

 

Could be the rom but usually it is the mbc chip or the board. Look for water damage, if it is clean it's probably the mbc.

 

Both of the games have suffered water damage in the past. Is there any testing I could do? I can open them.

 

Opening it and cleaning any corrosion would be a good start. Then look for damage done by the corrosion.

 

I cleaned them in the past, but with no change. I'll take pictures.

 

Here's some pics.

Symptoms:

Game Cart: https://onedrive.live.com/redir?resid=DB065D31B19F9386!74406&authkey=!AHlozmQOu5Zxtac&ithint=album,

I just re-cleaned the contacts of the game. The second one I'd meantioned before is somehow now working! (knock on wood) and is shown for comparison in the album.

Any ideas? I couldn't really find any damage.. and the contacts are clean. Honestly I found this game under a picnic table when I was much younger.. its never worked.

-Noah

*edit Wholly crap those pictures are big, can I re size them? sorry I'm new to not being a lurker*

 

Easiest way to clean that corrosion is to remove the battery (it's probably nearly dead anyways) and wash the whole board in a salt and vinegar solution (this will dissolve most corrosion in less than a minute), Rinse with soap and water. If it is still dead look at the traces for ones where it turned to a dirty pink color, that means that the gold plating is gone, check those for continuity.

Edit: check that scratch at the bottom of photo 11, and reflow the pins of the mask rom.

 

Looks like it's not loading some part of the ROM such as sprite images. Since the game seems to run, I think it could be an issue with memory controller.

 

assuming the issue is corrosion from the water damage(which it may not be) I would just take some 90%+ iso alchohol and a soft bristled toothbrush and clean everything really well--if there is actually a solder issue you could try a reflow or desolder/resolder with a hot air rework station as mentioned above

if that doesn't do it you could start by tracing the connections to the cart edge and making sure a trace didn't get cut(running a small magnet wire etc if one has been), if that doesn't do it you could start testing the components, alot of the stuff on a pcb will take a surprising amount of abuse and still function

 

Thanks for the advice! I got the game working again. The trace hadn't been cut, but I gave the game a bath and re-flowed all the chip pins. The game works now. Thanks a ton guys! All it needs now is a new battery (which I have in the garage)