MV4FT issue, a strange one (or is it???)

[Dexx1981]

i have a MV4FT board that had some battery corrosion on the board, it worked fine but then it started to give me the click of , i checked the AS245 chips close to the BIOS and 68K cpu because they looked very crusty, soldered new sockets and installed new AS245 chips.. still the click of death... so yeah, i tried to boot it without the AS245 chips and...



you would think it has to be something with the AS245 chips which it can't be that because they are new, checked all the traces for continuity and they are fine.
if i insert chips in one of these sockets, doesn't matter which one, i'll get garbled screen and the click of death.. everything else works fine.


so what could be the problem?

EDIT: i replaced the NEO-G0, no luck.

 

[Dexx1981]

so no one knows what's wrong i guess anyway, i got a MV4FS from a friend now.

 

[Neo Alec]

Did you try any bioses besides the original and diag? Maybe it's the bios.

 

[Dexx1981]

Did you try any bioses besides the original and diag? Maybe it's the bios.

as you can see, i tried the diag bios and it passed the test without the 2 AS245 chips, other bioses act exactly the same.

 

[Neo Alec]

as you can see, i tried the diag bios and it passed the test without the 2 AS245 chips, other bioses act exactly the same.

So with a Unibios you still get the click of death?

 

[Dexx1981]

So with a Unibios you still get the click of death?

yep

 

[lithy]

I barely know how logic probes work, but I'd be curious if maybe you could find a line that is stuck. I know you said you have some sketchy looking traces but they check out with a multimeter. I believe I've seen mentioned that corroded traces could show continuity but still cause issues.

Again this is just shot in the dark type stuff from me, zero experience with an issue like this, just trying to think of something that could be going on.

 

[Dexx1981]

I barely know how logic probes work, but I'd be curious if maybe you could find a line that is stuck. I know you said you have some sketchy looking traces but they check out with a multimeter. I believe I've seen mentioned that corroded traces could show continuity but still cause issues.

Again this is just shot in the dark type stuff from me, zero experience with an issue like this, just trying to think of something that could be going on.

hmm, that could be it.. but, if it's under the white 64pin connector... that's gonna be a pain in the

 

[dragonpt]

Sorry to hijack but, i do have the very EXACT issues with an mv4f that was given to me.
The board was stuck on click of death.

Had some corrosion around the battery, took out the batt, and clean all with vinegar and ipa, all traces seem good and have continuity.

Doesn't matter if i use stock/ unibios / diag, still goes to CoD

I went and replaced with brand new ones:

32k RAMs
2k RAMs
Backup rams
Work rams

No Joy, still stucked

Went and removed the 7, 245's ICS, since they are known to go bad very Often, put some sockets, replaced with brand new ones, still won't boot and click off death.

Went and started testing without the 245's on, and the board would now boot, but with some slightly gfx issues around the letters ( maybe sfix related? )

With the 245's on, excepto those two, the board still boots INTO the diag bios/ unibios

On the diag bios, all test passed, but i dont have color bars , just some weird gfx garbage instead.
with unibios i have color bars, but that's because unibios uses some "hacks" to generate them, while diag bios uses the palettes from sfix.

Also on the diag bios, i do have some player 2 inputs IN ( this is coming from neo C1/ or the resistors array) need to check this better...

https://imgur.com/a/2bfXXUV

 

[Dexx1981]

Sorry to hijack but, i do have the very EXACT issues with an mv4f that was given to me.
The board was stuck on click of death.

Had some corrosion around the battery, took out the batt, and clean all with vinegar and ipa, all traces seem good and have continuity.

Doesn't matter if i use stock/ unibios / diag, still goes to CoD

I went and replaced with brand new ones:

32k RAMs
2k RAMs
Backup rams
Work rams

No Joy, still stucked

Went and removed the 7, 245's ICS, since they are known to go bad very Often, put some sockets, replaced with brand new ones, still won't boot and click off death.

Went and started testing without the 245's on, and the board would now boot, but with some slightly gfx issues around the letters ( maybe sfix related? )

With the 245's on, excepto those two, the board still boots INTO the diag bios/ unibios

On the diag bios, all test passed, but i dont have color bars , just some weird gfx garbage instead.
with unibios i have color bars, but that's because unibios uses some "hacks" to generate them, while diag bios uses the palettes from sfix.

Also on the diag bios, i do have some player 2 inputs IN ( this is coming from neo C1/ or the resistors array) need to check this better...

https://imgur.com/a/2bfXXUV

ah yes, i ended up giving the board to a friend, maybe he can fix it i got a free MV4FS back which does have a VG2430 battery, replaced that one with a Lir2477, i really hope you get yours working again.