Neo Geo AES 3-6 red screen without game installed.

aapuzzo

n00b
Joined
Oct 18, 2023
Posts
10
I am new user that just bought a broken AES from Japan on Ebay because I love collecting and repairing game consoles. I purchased it with the belief it wouldn't power on but it instead gives me a red screen without a game installed. I'm using a Genesis model 1 transformer to power the unit as it did not come with a power adapter. My initial research leads me to believe this is a work ram error so I ordered 4 CXK58257AM-10L chips in place of CXK58257AM-12L. I think the 10L just stands for the speed in nanoseconds and faster is fine. The chips I could licare with 12L would take a month to get here from China and I'm impatient. The motherboard looks to be in way better condition than I expected for being so old. I have been testing continuity the best I can for the 2 CXK58257AM-12L near the edge of the board on the same side as the AV power ports because I believe these are the work ram chips. Some of the traces can be tested between the 2 memory chips and the rest seem to go to LSPC2. Other than waiting for the new memory chips to come in the mail is there anything else I can try. Am I testing the correct CXK58257AM-12L chips? There seems to be 2 more on the board which is why I ordered 4. I can provide pictures if it would help.
 

BIG BEAR

SHOCKbox Developer,
20 Year Member
Joined
Dec 14, 2001
Posts
8,196
One set is video ram.
I'm looking at a 3-5 which is similar to a 3-6 and that's the video ram up top near the lspc2 and work ram near the reset button.
BB
 
Last edited:

channelmaniac

Mr Neo Fix-it
15 Year Member
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Nov 29, 2005
Posts
4,275
Work RAM has the address lines and data lines connected to the CPU. Video RAM has them connected to the LSPC chip.
 

aapuzzo

n00b
Joined
Oct 18, 2023
Posts
10
Thanks happy I asked I just spent the last 2 hours checking continuity on the wrong thing. :LOL: Where can I find a diagram with the chip locations?
 

aapuzzo

n00b
Joined
Oct 18, 2023
Posts
10
I found the issue and have a blue screen now. I don't have a game to fully test because I didn't want to buy one until I knew I had a working console. There was actually a non visible hairline crack in the board which you can see inside the red circle. Weird spot for a crack and was probably due to a poor design if I had to guess. There wasn't any copper showing though. I exposed it by barely scratching with my fingernail. This caused one of the working traces to stop working and I located the original problem one right next to it. The pins on the "working ram" chips that were broken were actually the only pins that seem to go to a totally different spot on the board. They were the hidden vias under the memory chips labeled WE/U17 that a found in an image by Maki on this forum. I attached the image below. Now I am debating on the correct way to fully resolve this issue as technically all the traces in that area will probably break in time when inserting a cartridge. Do you think I should jump all the traces out in the area to existing solder points or should I try and expose the copper in the area and lay a fine strand of wire over each trace and solder it in? The blue jumper wires are 30 gauge for a size comparison to the traces.


20231019_014751.jpg

MV1FZ Backup RAM.jpg
 

Neo Alec

Ned's Ninja Academy Dropout
20 Year Member
Joined
Dec 7, 2000
Posts
11,742
Yeah, a blue screen is great progress, but you never know if things are 100% until you test with a game. You'd better confirm what you're dealing with before proceeding.

How many traces are we talking? I personally don't mind jumping them all as long as the wiring doesn't obstruct anything, but do what you're comfortable with.
 

aapuzzo

n00b
Joined
Oct 18, 2023
Posts
10
Yeah, a blue screen is great progress, but you never know if things are 100% until you test with a game. You'd better confirm what you're dealing with before proceeding.

How many traces are we talking? I personally don't mind jumping them all as long as the wiring doesn't obstruct anything, but do what you're comfortable with.
I jumped all 10 out the other night and now waiting for a cartridge to come in the mail. Tried locating one locally but no luck. I think the break was caused because the bottom shell has a flat standoff that pushes pressure in that spot. The shell definitely isn't as ridged as the main stream consoles were. The other 8 traces were much easier to jump because they all had continuity over the crack. I didn't have to hunt around. That type of break wouldn't cause a short across the traces especially since I cleaned the area with a razor.
 

aapuzzo

n00b
Joined
Oct 18, 2023
Posts
10
Just received my 161 in 1 v3 cart in the mail and it's completely working. I guess I lucked out on this one.
 
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