A3000 HD/battery issues

I recently purchased an A3000 from Ebay. The seller claimed the Amiga was tested working and the HD had Workbench installed.

After setting it up and turning it on, the HD light comes on and flashes a bit but it's stuck on the Kickstart screen. The early startup menu shows that the Amiga isn't detecting the HD - only DF0: is listed.

I opened up the box to make sure nothing had come loose during shipping and it didn't seem to have, but then the area around the battery caught my eye.

It didn't look like it's actively leaking, but it looks like a previous battery was, and that maybe the former owner didn't exactly do a bang up job tidying up the mess. The guy who sold it told me that he knew that the battery in there wasn't the original, but also wasn't the guy who changed it and didn't have any idea when it was last changed.

So I have a few questions. Could that nasty acid damage be responsible for my boot issues? Is this Amiga beyond repair/should I try to get a refund?

Also, I'm curious about the component south of the battery sandwiched between the two chips - the yellow thing. Its look to be in a particularly bad state - it's not totally obvious from the photo, but it seems to have those leaky battery white crystals inside of it (ugh). Anyone know what that is and if it needs replacement?

[Daedalus]

The A3000 stores some of its settings in battery backed-up RAM (NV-RAM), so if the battery is dead or not connected properly, that can cause it from booting. Setting the SCSI settings to what they should be might let you boot, and maybe the battery's simply flat, in which case leaving it powered on all day will charge the battery and keep the settings. Looking at the photo though it does indeed seem like either the new battery is leaking, or the caustic chemicals released by the previous battery are still there and still slowly eating away at traces, including those that provide power to the NV-RAM.

It's probably repairable, but if you paid for a fully working Amiga, unless the battery's simply flat, that's not what you got. Up to you whether it's worth trying to return it for a refund or perhaps getting the cost of repair refunded by the seller.

The yellow component with the hole in the centre is a small trimmer capacitor. It's used for fine-tuning the real-time clock, compensating for manufacturing tolerances in the crystal so that the internal timekeeping is as accurate as possible. It should be easily replaced.

[lost_loven]

Cut the battery out or unsolder.. neutralize the infected area.. I used clear nail polish to protect it. install new battery or solder wires to points like I did and have battery away from mother board.. Hd worked fine for me till I added a new one. Really should be cleaned up better from looking at that pic.

[Lianna]

That's a fair bit of (repairable) damage, though I'm not sure it would cause booting issues or your HD to not be detected as the SCSI logic is probably mostly if not entirely on the other side of the board.

You should at least take that battery out and neutralize the acid with vinegar, and then repair it or get it repaired, if you're not returning it to the seller of course. You can replace the battery with a Lithium coin cell (along with a diode, you wouldn't want the system to try charging it).

For the HD, is the SCSI chain properly terminated on both ends?

Thanks for the help, everyone.

Originally Posted by Daedalus

The A3000 stores some of its settings in battery backed-up RAM (NV-RAM), so if the battery is dead or not connected properly, that can cause it from booting. Setting the SCSI settings to what they should be might let you boot, and maybe the battery's simply flat, in which case leaving it powered on all day will charge the battery and keep the settings.

The seller actually suggested I let it idle for half an hour because apparently he's seen some A3000s (not this one) where the "battery needs a little bit of a charge to see the SCSI settings"; I tried it - though I probably didn't wait the full half hour - but it didn't seem to work.

Is there any way to adjust the SCSI settings without being able to boot? I didn't see anything on the early startup menu...

Originally Posted by Daedalus

Looking at the photo though it does indeed seem like either the new battery is leaking, or the caustic chemicals released by the previous battery are still there and still slowly eating away at traces, including those that provide power to the NV-RAM.

If I'm gonna go in there and clean, what should I be looking for that'd indicate that it's still leaking/that there's still chemicals kicking around?

Originally Posted by Lianna

You should at least take that battery out and neutralize the acid with vinegar, and then repair it or get it repaired, if you're not returning it to the seller of course.

It's been a while since Grade 10 chem class, and I'm sure I'm just a dummy, but, uh, isn't vinegar acidic? Wouldn't something basic like baking soda work better for neutralizing battery acid? (although maybe that wouldn't go down so well on a PCB...?)

Originally Posted by Lianna

For the HD, is the SCSI chain properly terminated on both ends?

Well, I have a terminator plugging into the SCSI port on the back, at least. Is there anything else I need to do to ensure it's correctly terminated? There's a ribbon cable from the port but it's one of the central connectors that's connected to the HD, not the one at the other end. Is that a problem?

[ajk]

The electrolyte in NiMH batteries is usually potassium hydroxide, which is alkaline. "Battery acid" is a bit of a misnomer here.

[glenn]

Originally Posted by wk_end

The seller actually suggested I let it idle for half an hour because apparently he's seen some A3000s (not this one) where the "battery needs a little bit of a charge to see the SCSI settings"; I tried it - though I probably didn't wait the full half hour - but it didn't seem to work.

Its not that it need to charge, the problem is that if the battery is dead the machine go into default SCSI settings, and those settings have a veeeery long timeout, so it can take a very long time before it start to boot, I guess 30min is fully possible.

Is there any way to adjust the SCSI settings without being able to boot? I didn't see anything on the early startup menu...

Boot from floppy and run battmem ?

Floppy shouldnt be affected from SCSI settings.

[Lianna]

Originally Posted by wk_end

If I'm gonna go in there and clean, what should I be looking for that'd indicate that it's still leaking/that there's still chemicals kicking around?

It's caused a lot of oxidation already on various components and solder joints, looks pretty nasty, and it just doesn't look like it was properly cleaned. Take R190 for example on its right leg, that looks like battery chemicals to me.

The picture shows what looks like the original type of battery, and it may not be leaking right now, but it will leak again at some time in the future (could be many years, if it's a new battery). Lithium coins won't leak though, so that's a much safer option. AmigaKit has a great replacement part for these.

U195 (74LS174, D-type Flip-Flop apparently - common and cheap IC) has a lot of oxidation on its pins, and should certainly be replaced. It also gives the suggestion there's still chemicals there on those pins.

The cluster of resistors and diodes at the positive edge of the battery are also due a replacement due to the oxidation there, and the traces there will probably need to be repaired or jumpered.

R469 has some damage, not sure there's still chemicals there but it looks nasty and that resistor may no longer have a ground connection. The solder joint at the positive end looks dull and corroded, and even further to the right (between R470 and C482) those solder joints don't look healthy.

Originally Posted by wk_end

It's been a while since Grade 10 chem class, and I'm sure I'm just a dummy, but, uh, isn't vinegar acidic? Wouldn't something basic like baking soda work better for neutralizing battery acid? (although maybe that wouldn't go down so well on a PCB...?)

Been a while for me as well and I was never any good at the subject. But that's what people say it neutralizes the stuff so I go with it. Of course you'd also clean that off again with IPA after letting it sit for a little while.

Originally Posted by wk_end

Well, I have a terminator plugging into the SCSI port on the back, at least. Is there anything else I need to do to ensure it's correctly terminated? There's a ribbon cable from the port but it's one of the central connectors that's connected to the HD, not the one at the other end. Is that a problem?

If the termination is enabled on the HD as well then that should be fine. Did you check connectors are properly seated, no bent pins, drive is powering up, etc?

[Daedalus]

Originally Posted by wk_end

The seller actually suggested I let it idle for half an hour because apparently he's seen some A3000s (not this one) where the "battery needs a little bit of a charge to see the SCSI settings"; I tried it - though I probably didn't wait the full half hour - but it didn't seem to work.

As others have said, if the settings are lost due to lack of battery power, they're lost. Charging isn't going to bring them back.

Is there any way to adjust the SCSI settings without being able to boot? I didn't see anything on the early startup menu...

I'm not so familiar with specifics of the A3000 - there are a number of differences from most other Amiga models. There must be a way to set the preferences however - some utility on the boot disk for example (the A3000 has a special "Super Kickstart" disk that other Amigas don't have).

If I'm gonna go in there and clean, what should I be looking for that'd indicate that it's still leaking/that there's still chemicals kicking around?

Any staining or crystalline deposits around the battery itself are an indication that it's not in the best of health. To be honest, I'd be inclined to replace the battery anyway with a lithium cell and a diode to avoid having it leak in the future, even if it's perfectly healthy now.

As for the corrosive chemicals on the board, if you neutralise them with acid (vinegar or lemon juice will work fine), it will fizz and bubble until it's all gone. Keep applying it with a small brush until it doesn't fizz any more, then clean it away with IPA (the 99.9% stuff, not the 70% stuff). You'll still be left with the corroded parts, but a lot of what you see should come away very easily.

Well, I have a terminator plugging into the SCSI port on the back, at least. Is there anything else I need to do to ensure it's correctly terminated? There's a ribbon cable from the port but it's one of the central connectors that's connected to the HD, not the one at the other end. Is that a problem?

Hmmm... There should always be a device or terminator on the physical end of the cable. If there is, the other positions don't matter. If the end of the cable's just floating, that's not good. If it was working before you got it though it should be fine unless the seller wasn't telling you something...

Thanks again for the help and wisdom.

I used some vinegar to get some idea of how much leakage was there. There was a tiny bit of fizzing right around the base of the battery, but nowhere else. I then did my best to scour everything with rubbing alcohol and an old toothbrush.

Right now I'm trying to get the old battery out - I didn't expect I'd have disassemble the whole damn thing to desolder it, or what a pain it'd be. That leads to an embarrassing question: how does one detach the motherboard from the case? There were a couple of screws, but then there's also these things, and I don't know how to deal with them.

[KronusOfChaos]

Just use a pair of plyers on those. But be careful not to twist too hard other wise they could break off. They are really no different than screws. It's just used to keep the processor card stable in the system and keep the case down.

Perfect, thanks, that did the trick. Battery removed.

[glenn]

Originally Posted by Daedalus

I'm not so familiar with specifics of the A3000 - there are a number of differences from most other Amiga models. There must be a way to set the preferences however - some utility on the boot disk for example (the A3000 has a special "Super Kickstart" disk that other Amigas don't have).

Only early A3000 have this, it is because they have "Superkickstart" ROM's.

But since those are not compatible with anothing except 68030 most machines probably have had the ROM's replaced with 3.1 ROM's today.


About the termination, from factory the A3000 have a termination on the motherboard, but since this should be removed if you want to use external units most machines have this termination removed (I think it was even soldered in some revisions), and if it is removed you should have an external termination in the end of the chain. (And one internal, usally a harddisk with termination)