Error code 5555 0055

[Sirgubster]

Read around a bit. People at klov told me this is the place to ask. 1 slot board was working great and then all of a sudden went out about 20 seconds or so into the game playing. I turned it off and back on again and that's the error I got. Read some people having similar issue but the advice was more confusing then the question. Anybody able to walk me through fixing this. I own a multi meter. It's the bigger one slot board with credit display connections. Thanks in advance.

 

[littlecharlie]

You have a problem with the upper Backup RAM.
You need to check the traces going from/to that IC, see if there is any broken trace. MOst likely if your old battery has leaked.
It might be also a bad chip. If so you'll need to replace that IC (32K x 8bit SRAM).
Or it's often the 74HC32 close to the RAMs going bad (on mv1a mv1fz boards)

If you want to bypass that error, try a unibios instead of the stock one.

More info here

RAM chip - NeoGeo Development Wiki

wiki.neogeodev.org

neogeo-diag-bios/ram.md at master · jwestfall69/neogeo-diag-bios

Disassembly of smkdan's Neo Geo Diagnostics BIOS with added features - neogeo-diag-bios/ram.md at master · jwestfall69/neogeo-diag-bios

github.com

 

[Sirgubster]

You have a problem with the upper Backup RAM.
You need to check the traces going from/to that IC, see if there is any broken trace. MOst likely if your old battery has leaked.
It might be also a bad chip. If so you'll need to replace that IC (32K x 8bit SRAM).
Or it's often the 74HC32 close to the RAMs going bad (on mv1a mv1fz boards)

If you want to bypass that error, try a unibios instead of the stock one.

More info here

RAM chip - NeoGeo Development Wiki

wiki.neogeodev.org

neogeo-diag-bios/ram.md at master · jwestfall69/neogeo-diag-bios

Disassembly of smkdan's Neo Geo Diagnostics BIOS with added features - neogeo-diag-bios/ram.md at master · jwestfall69/neogeo-diag-bios

github.com

So your saying I could In theory just switch out the bios and skip all this other complicated stuff to get it working?

 

[littlecharlie]

you'll might get around that error and play games, but the backup ram system won't work
worth a try

 

[Sirgubster]

you'll might get around that error and play games, but the backup ram system won't work
worth a try

will give this much easier route a try first. thanks!!!

 

[maki]

So your saying I could In theory just switch out the bios and skip all this other complicated stuff to get it working?

best outcome is to get it working temporary by ignoring any errors, until it totally fails or crashes during the games, thats if you're lucky

these things need maintenance, battery needs to be removed or it will leak and that will kill the back RAM first (battery is next to it)

 

[Sirgubster]

best outcome is to get it working temporary by ignoring any errors, until it totally fails or crashes during the games, thats if you're lucky

these things need maintenance, battery needs to be removed or it will leak and that will kill the back RAM first (battery is next to it)

Removed the battery already. On my other board I installed a new non leaking style one.

 

[maki]

can you take some good pics around the backup ram/battery area?
sometimes boards are too far gone, often that is very obvious

otherwise, its worth fixing these issues, but its a learning curve, not worth learning it if that the only MVS you want to fix IMO
there is people in this forum that offer to fix it as service

the error message btw. is rather clear about the problem, 0's instead of 5's on the two higher bytes, check the traces

whats the actual MVS?

 

[pierpa86]

I got the same error yesterday, solved replacing the 74hc32 and ram 1 to 4.
I replace the ram for the best result over time and because i got a lot of ram spare to use.
Some time replace only the hc32 will solve the issue.

 

[Sirgubster]

can you take some good pics around the backup ram/battery area?
sometimes boards are too far gone, often that is very obvious

otherwise, its worth fixing these issues, but its a learning curve, not worth learning it if that the only MVS you want to fix IMO
there is people in this forum that offer to fix it as service

the error message btw. is rather clear about the problem, 0's instead of 5's on the two higher bytes, check the traces

whats the actual MVS?

Will take some super good pics and get them uploaded thank you.

 

[Sirgubster]

I got the same error yesterday, solved replacing the 74hc32 and ram 1 to 4.
I replace the ram for the best result over time and because i got a lot of ram spare to use.
Some time replace only the hc32 will solve the issue.

Do I just need to replace the chips or do they have to be programed as well?

 

[pierpa86]

just swap it, no need program.

 

[Sirgubster]

can you take some good pics around the backup ram/battery area?
sometimes boards are too far gone, often that is very obvious

otherwise, its worth fixing these issues, but its a learning curve, not worth learning it if that the only MVS you want to fix IMO
there is people in this forum that offer to fix it as service

the error message btw. is rather clear about the problem, 0's instead of 5's on the two higher bytes, check the traces

whats the actual MVS?

 

[maki]

to me the PCB and traces look good, including the battery area, nothing obviously defective, well worth saving

IIRC the backup RAM are those two SRAM ICs closest to the battery (43256), check those traces with a MM, could be that one is dead

 

[Sirgubster]

to me the PCB and traces look good, including the battery area, nothing obviously defective, well worth saving

IIRC the backup RAM are those two SRAM ICs closest to the battery (43256), check those traces with a MM, could be that one is dead

I can do that. Ya everything looked OK to me as well, just by my eye that is. Also I swapped in a unibios and I was able to play now. I had to choose the force button. So I don't know if that changes things. Let me know. Thanks. I definitely don't want to have to choose to force everytime of course

 

[Sirgubster]

Anyway to make it so I don't have to choose force everytime? Trying to avoid the whole using a soldering iron.

 

[Neo Alec]

This is a common symptom of damage from a leaky battery. There's no way around that without soldering to repair the damaged traces. If it's the case that no traces are damaged, then that error could only be bad sram IC's. Replacing those would also require soldering.

 

[Sirgubster]

This is a common symptom of damage from a leaky battery. There's no way around that without soldering to repair the damaged traces. If it's the case that no traces are damaged, then that error could only be bad sram IC's. Replacing those would also require soldering.

bummer but thanks for the info. I can solder im just extremely bad at it so i was trying to avoid that ha ha. I can still play it using the force method, but obviously I dont want to have to press the force button every time to play. Maybe down the line when i get some more time in my garage i can attempt to replace the ICs thank you.