Another A3000 with battery damage. Can we save this one?

[sev]

I have a A3000D that had some battery corrosion, Ive been working on cleaning it up and tryign to get this guy to run, but no luck so far.

It's a revision 8.9 board, I popped over the DIP ram from the chip ram area over to the fast ram area and removed the ZIP ram from the system. I did this because I have a suspicion the ZIP ram wasnt correctly socketed and I want to remove it as a troubleshooting item.

Basically the system when you turn it on, the VGA monitor gets video signal, but not much else. The Power LED does nothing but stay on solid.

The CPU and other chips seem to warm up, but nothing else happens. I have kickstart 3.1 roms in place.

Here are some photos:

[vince_6]

There was an A500+ with more damage than this.
What I did, I cleaned everything then resolder the components.
Some wires bypassed but nothing happened.
Then I saw that almost all sockets had corrosion too inside (between chips pins too)
68K paula even denise, the most damaged one was gary.
So I cleaned them too and changed ROM chip cause was burned.

Now it works just five.

[sev]

I removed the capacitor with a bunch of corrosion under it. THis is what it looks like.

Where does this connect? looks like one of the pins goes nowhere.

[vince_6]

I think u must solder the negative next C letter, scratch the paint first and the positive next to the hole that it was which has some better copper surface.
Check a good photo of another mobo as a guide to be sure.

[QuikSanz]

If looking at C190 you can clearly see the plus trace down to that resistor, the ground  connects to that ground area that used to be around there.

[Oldsmobile_Mike]

I cringe just looking at these pictures.  Good luck!

[Castellen]

The damaged tracks shown connect to vias which route the signal between different layers on the board.  Most signals are on top/bottom layers, +5V and ground are mostly on the internal two layers.

As opposed to just scratching at the corroded tracks, you need to check continuity then repair tracks and vias if they're open circuit.  I wrote this guide which may help.  It's for the A4000, but the A3000 PCB is much the same - it's still 4 layers.

Use something less damaging than whatever you're using now.  A fibreglass brush works well, e.g. Radio Spares part no. 514-868

Looking at your images, the U400 and U450 sockets are probably corroded as well and will need replaced.

[QuikSanz]

Certainly need pics of the various layers and then remove everything. Clean well, replace parts and jump what you need to. No small task!

[slaapliedje]

I can hear 'Taps' playing in the background...

Good luck, hopefully you can Lazarus this this one.

slaapliedje

[gertsy]

The damaged tracks shown connect to vias which route the signal between different layers on the board.  Most signals are on top/bottom layers, +5V and ground are mostly on the internal two layers.

As opposed to just scratching at the corroded tracks, you need to check continuity then repair tracks and vias if they're open circuit.  I wrote this guide which may help.  It's for the A4000, but the A3000 PCB is much the same - it's still 4 layers.

Use something less damaging than whatever you're using now.  A fibreglass brush works well, e.g. Radio Spares part no. 514-868

Looking at your images, the U400 and U450 sockets are probably corroded as well and will need replaced.

Perhaps there's an option to pack up the MB and send it to a professional. Perhaps not to Antarctica though.

[narcea]

I'm a IPC Specialist with JST and IPC610 certs. My certs are current. I don't know about taking on extra work but I would be willing to take a look at it especially if can't get it going.

I miss my A3000. I traded it in many many years ago for a laptop and a C128. I hadn't used in in so long up to that point and I thought at the time it was a good deal but in retrospect I should have kept it.

[CodePoet]

Hello,

If Narcea isn't an option due to distance (unspecified), I'm also willing to help you out with this - I'm in Sydney, Australia

[sev]

i did something stupid trying to unsolder the 74ls174 chip right above the battery damage, i wanted to see if there was damage underneath and ended up lifting 3 or 4 pads on that chip...


i think im going to give up...