Neo Geo won't boot (now with Video!)

[ebichu]

Hello there,

I got a defective Neo Geo AES System which won't boot anymore.
When I got it I put in a Game and switched it on. It only brings the "Neo Geo" Logo while playing the jingle, then it "reboots" and the same procedure happens again.

First thing I thought was that the Bios may have been corrupt. So I desoldered the original Bios Chip, soldered in a socket and put a new Eprom with UniBios in.

Now the Neo Geo starts with the UniBios Menu and some error codes..



First screen I get when I turn on the Neo:

After pushing reset button:

After pushing reset button again..

and again...

and again....

Sadly I got no Joystick to access any of the UniBios' menus so this is all I can show you. Can anyone (maybe Raz?) tell me what that mess means? I doubt it's not the Bios' fault, because I tried different UniBios versions and also the old DebugBios (brings similar error messages like the UniBios).

Sometimes there is no UniBios error screen after resetting. Then I got only a black screen and a permanent cracking sound out of the speakers.

Is there any hardware failure which I can fix? I hope so..

Thanks alot for your help

-ebichu

 

[Xian Xi]

Clean the cart edge and the slot.

 

[ebichu]

I guess you don't know the meanings of the error codes? I don't think it's just cleaning, and yes: I already did it

 

[Xian Xi]

I guess you don't know the meanings of the error codes? I don't think it's just cleaning, and yes: I already did it

Obviously your system says it can't read something. Usually it's due to either a dirty cart/slot, broken trace(s), bad ram, etc. Start with the easier one.

Raz is the only one who knows what the codes mean I believe.

 

[ebichu]

Well yeah, that's why I hope that he's showing up here to tell what this all means
I already cleaned the Slot/Cart and my soldering skills are very good (I solder every day @ work since years). And the Neo Geo couldn't read any game from the beginning, before I was doing anything on it. So I don't think that it has to do with broken traces or something caused by soldering.

 

[Razoola]

Need more info.... What version of the unibios are the screenshots from? At a guess Im leaning towards a bad high address line solder/trace. maybe this will help...

This info is taken from NEO-AES3-6 and NEO-AES3-4 revision boards
and should be valid for all boards that have the bios to the right
of the cart slot. The older board NEO-AES which has the bios
above the cart slot is partly different.

* The 43256 (work RAM) closest to P1 joystick port

1----5V
2----GND
3----68000-12 (54), LSPC2 (21), NEO G0 (50)
4----68000-12 (55), LSPC2 (20), NEO G0 (49)
5----68000-12 (56), LSPC2 (19), NEO G0 (48)
6----68000-12 (57), LSPC2 (18), NEO G0 (47)
7----68000-12 (58), LSPC2 (16), NEO G0 (34)
8----68000-12 (59), LSPC2 (15), NEO G0 (33)
9----68000-12 (60), LSPC2 (14), NEO G0 (32)
10---68000-12 (61), LSPC2 (13), NEO G0 (31)
11---GND
12---68000-12 (62), LSPC2 (10), NEO G0 (18), 43256* (19)
13---68000-12 (63), LSPC2 (09), NEO G0 (17), 43256* (18)
14---68000-12 (64), LSPC2 (08), NEO D0 (03), 43256* (17)
15---68000-12 (01), LSPC2 (07), NEO D0 (02), 43256* (16)
16---68000-12 (02), LSPC2 (05), NEO D0 (01), 43256* (15)
17---68000-12 (03), LSPC2 (04), NEO D0 (64), 43256* (13)
18---68000-12 (04), LSPC2 (03), NEO D0 (63), 43256* (12)
19---68000-12 (05), LSPC2 (02), NEO D0 (62), 43256* (11)
20---NEO E0 (59)
21---68000-12 (29), NEO E0 (64), 43256 (10), HC259 (01)
22---68000-12 (30), NEO E0 (01), 43256 (09), HC259 (02)
23---68000-12 (31), NEO E0 (02), 43256 (08), HC259 (03)
24---68000-12 (32), NEO E0 (03), 43256 (07), HC259 (13)
25---68000-12 (33), NEO E0 (04), 43256 (06)
26---68000-12 (34), NEO E0 (15), 43256 (05)
27---68000-12 (35), NEO E0 (16), 43256 (04)
28---68000-12 (36), NEO E0 (17), 43256 (03)
29---68000-12 (37), NEO E0 (18), 43256 (25)
30---GND
31---68000-12 (38), NEO E0 (19), 43256 (24)
32---68000-12 (39), NEO E0 (20), 43256 (21)
33---68000-12 (40), NEO E0 (21), 43256 (23)
34---68000-12 (41), NEO E0 (31)
35---68000-12 (42), NEO E0 (32)
36---68000-12 (43), NEO E0 (33)
37---68000-12 (44), NEO E0 (34)
38---5V (N.C. on NEO-AES3-4)
39---5V
40---5V

Fault checking.


If for some reason the system no longer works then obiously some traces
have broken, check everything.

If the Bios is working but you get a memory card error on power up if a
memory card is inserted and a card protected error while trying to format
a memory card then one or more of the socket to NEO E0 traces have
broken (pin 20 to 37).

 

[ebichu]

It's from Version 2.3
What more Info do you need?

 

[channelmaniac]

Put the original BIOS back in. Remove any cartridge. Power it on. Power it on many times. What color screens do you get?

If you aren't getting a colored screen that equates to a memory problem then you most likely have a slot problem. It's either dirty or it is loose.

If it's dirty take a bit of rough poster board and fold it in half a couple of times to make it a ever so slight larger (not much!) than the cartridge board itself, put pure alcohol on it, and insert/remove it a bunch of times from the cartridge slot. The paper will act as an extremely mild abrasive and the alcohol will help remove the gunk from the slot contacts.

Be sure to use pure alcohol. The stuff you get from the drugstore is typically 30 to 70 percent WATER.

RJ

 

[ebichu]

Thanks for your advice but I already cleaned everything with Iso Alcohol (98%). That's what I always do before making anything other.

@Razoola: what more info do you need? Is there any blueprints for Neo Geos on the web to look at? Just tell me what you need and I'll try to show it here.

Edit: and for what is the table you posted here, Raz? I can't follow exactly..

 

[Xian Xi]

Did you check your traces for any bad ones?

 

[ebichu]

No, but as I said: the Neo Geo won't boot from the beginning, way before I even heaten up my soldering iron. So the error was there before.

 

[ebichu]

UPDATE! (sorry for double posting..)

I reinseret the original Bios Chip on my socket and just tried to start with a game: Neo Geo Logo appears together with the jingle sound, warning message of the game appeared......black....... nothing....

Then I tried to boot the neo without any cartridge inseret: most of the time nothing happens but I got a red screen one time!

So I guess there is an error with the working ram like Raz assumed..

Question: is there any possibility to repair this when I got another Neo Geo AES? Can I just change the working ram? I think yes, but wanted to ask before..

 

[Xian Xi]

No, but as I said: the Neo Geo won't boot from the beginning, way before I even heaten up my soldering iron. So the error was there before.

That doesn't mean a trace can't go bad if it's untouched. Even Raz said it was possible. Just do a visual on both sides of the board to see if there are any obvious ones. Hopefully if it is a trace it's an obvious one.

 

[channelmaniac]

If you were on this side of the world I'd say send it to me and I can replace that Work RAM. MKL in Italy can do it for you on that side of the world.

It's surface mount soldering.

 

[ebichu]

Traces are all good.
As I already mentioned I am soldering for years every day at work (SMD). So no problem with that.

I got another Neo Geo where I can take the Ram from. But for the case if you don't got another defective Neo Geo, is there any other piece of hardware that got this ram on? Like old GeForce graphics card got the Ram for the Xbox 1?

 

[Hewitson]

Not sure, but it can be bought on channelmaniac's site:

http://www.arcadecomponents.citymax.com/catalog/item/2251646/4758714.htm

 

[ebichu]

Whoah nice! That is a really cheap alternative. Thank you!

 

[Neo Alec]

I would have replaced the bad RAM on my Super Contra board, but it turns out I can't desolder chips from boards to save my life. I have yet to pull a chip off a board without ruining it. The people doing this successfully must be skilled solderers.

 

[channelmaniac]

Thanks guys.

I went to school to learn how to use the solder station. Granted, it was back in 93, but hey... you don't forget that stuff easily.

When I left the computer store to move into the Dallas area I kept in touch with the store owner. Nobody used the solder station for 2 years so I bought it. Back in the day I used to make money taking 4Mb 72pin SIMMs and converting them to 32Mb 72pin by stripping old 4Mb 30 pin SIMMs for parts. Made some GOOD money doing that.

If you still need that RAM chip swapped out still on that Super Contra send me a PM.

Ebichu, what are you using? I have 2 Pace MBT stations with a variety of irons and tips. One in the computer room in the house and one in the workshop out back.

I hope you liked my website. It's a hobby business and a labor of love. I repair boards to destress from the day job and keep my sanity. It beats paying for a shrink.

RJ

 

[Neo Alec]

If you still need that RAM chip swapped out still on that Super Contra send me a PM.

Thanks, but I bought a different board and eventually threw out the two bad ones I had. The one I have now still doesn't work perfectly. It's missing a non-critical component (the long bar that sticks out that says "Konami" on it). I tried to replace this with the one I had on one of the non-working boards, but I wrecked that too trying to remove it.

 

[ebichu]

@channelmaniac: I got a Weller Station with two Solder Irons at home and all that "hardcore" stuff like infrared soldering stations at work. I repair mobile phones, pdas, tomtom's and iPods, so enough experience with small parts

 

[norton9478]

Thanks guys.

I went to school to learn how to use the solder station. Granted, it was back in 93, but hey... you don't forget that stuff easily.

When I left the computer store to move into the Dallas area I kept in touch with the store owner. Nobody used the solder station for 2 years so I bought it. Back in the day I used to make money taking 4Mb 72pin SIMMs and converting them to 32Mb 72pin by stripping old 4Mb 30 pin SIMMs for parts. Made some GOOD money doing that.

If you still need that RAM chip swapped out still on that Super Contra send me a PM.

Ebichu, what are you using? I have 2 Pace MBT stations with a variety of irons and tips. One in the computer room in the house and one in the workshop out back.

I hope you liked my website. It's a hobby business and a labor of love. I repair boards to destress from the day job and keep my sanity. It beats paying for a shrink.

RJ

Hey,

Do you have the equipment to properly reflow a RROD 360 CPU/GPU with real solder?

Just wondering for future reference.

 

[channelmaniac]

Hey,

Do you have the equipment to properly reflow a RROD 360 CPU/GPU with real solder?

Just wondering for future reference.

No. That requires a BGA iron with suction to pull the chip off... the you have to clean it, reball it, clean the board, then reseat it with infrared or hot air. I don't do BGA as I don't have the tools or experience.

 

[ebichu]

Alright...
Today I changed the WorkingRam, all 4 Chips (marked in the following Picture) but I still get a red screen when turning on the Neo Geo without any Cartridge... ?

I made two videos, one with the original Bios inserted, the other one with UniBios.

Check this (original Bios): http://www.myvideo.de/watch/4022251/Neo_Geo_original_Bios

And this (UniBios): http://www.myvideo.de/watch/4022336/Neo_Geo_UniBios

Any1 an Idea? Anything other I can/should change? It drives me crazy. Note that "click click click" Sound on the UniBios Video..

 

[werejag]

its a trace to from the bios to the lower ram. im willing to bet