Neo Geo 2-slot Backup Ram Error

OldTymeToys

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I went to turn on the games in the game room for the kids last night and my Neo Geo came up with the following error:

BACKUP RAM ERROR
ADDRESS WRITE READ
00D00000 5555 0055

It is a 2 slot with only the 161-1 multicart installed.

Hopefully, it's something simple, but any help on this would be appreciated.
 
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Slowly... but yes,

Right now I had more shipped in so not taking any more yet. I have to balance family, a day job, and life with this. :)
 
Any idea folks?

If it still has the original battery on it then it's most likely a corroded trace going to one of the control lines on one of the backup RAMs. Check the traces and components around the 74HC32 next to the battery.

This comment is based on experience and that the RAM is outputting 00 at the base address of D00000.
 
If it still has the original battery on it then it's most likely a corroded trace going to one of the control lines on one of the backup RAMs. Check the traces and components around the 74HC32 next to the battery.

This comment is based on experience and that the RAM is outputting 00 at the base address of D00000.

Thanks- will do. I'll let you know what I find!
 
If it still has the original battery on it then it's most likely a corroded trace going to one of the control lines on one of the backup RAMs. Check the traces and components around the 74HC32 next to the battery.

This comment is based on experience and that the RAM is outputting 00 at the base address of D00000.

It still has the original battery that looks OK at first glance. I apologize for my ignorance, but I've never seen one of the "pads" stuck on the back of a pcb before. I tried to lift it but it's really stuck there and I was afraid to do damage pulling it off. I guess I need to pull it off to check the traces though... any other thoughts?

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Trace issues are almost always on the top of the board around the battery, not under the insulation pad. It's there to keep short circuits away that could cause excessive current draw on the battery.
 
Trace issues are almost always on the top of the board around the battery, not under the insulation pad. It's there to keep short circuits away that could cause excessive current draw on the battery.

Good to know, thanks! So I snapped these pics and after closer inspection, the only thing I noticed is the suspect solder pad circled. Could that be the culprit?

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The dark spots are damaged portions of traces. One of them will have been eaten. Concentrate on the ones around that 74HC32 next to that bad solder joint.


Thanks for the help! Ugh, now I've got some work to do. I might as well do the battery mod too, I guess.
 
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