Yet another simasimac SE/30 giving me grief

[mattsoft]

F1 has no continuity, so the ADB is not getting any juice! I presume it's ok to jump F1 for testing purposes until I can get a replacement component?

 

[mattsoft]

Last post on this thread: the SE/30 is all fixed! Bad fuse on F1 was keeping the ADB from working. I jumped it and everything now works. New poly fuses ordered to replace jumpers. Another SE/30 saved!

 

[chiptripper]

Appreciate the clues in this thread, helped a lot.

I have a clean SE/30 board that showed simasimac on boot for up to a minute. It cleared up eventually but there were lingering graphical glitches. It also wouldn’t boot at all with a purple 2MB ROM.

Really threw me for a loop. Tried everything, even replaced the ROM socket (probably needed to be done anyway.)

It was the SWIM! Swapped it out and now everything works perfectly.

 

[roymaya]

Appreciate the clues in this thread, helped a lot.

I have a clean SE/30 board that showed simasimac on boot for up to a minute. It cleared up eventually but there were lingering graphical glitches. It also wouldn’t boot at all with a purple 2MB ROM.

Really threw me for a loop. Tried everything, even replaced the ROM socket (probably needed to be done anyway.)

It was the SWIM! Swapped it out and now everything works perfectly.

Glad you got it working. I have a similar SE/30 with simasimac also. I've checked the simm sockets, tried different Simms, checked for broken traces even bought a PDS rom thinking it might be a bad rom socket but still no luck. Might gut keeps telling it's also bad IC, probably the SWIM likes yours.

 

[croissantking]

Glad you got it working. I have a similar SE/30 with simasimac also. I've checked the simm sockets, tried different Simms, checked for broken traces even bought a PDS rom thinking it might be a bad rom socket but still no luck. Might gut keeps telling it's also bad IC, probably the SWIM likes yours.

Is that simasimac with chimes of death, or silent?
My money is on a broken trace. You should open up a new thread to get into more detail and post some pics of the board.

 

[roymaya]

Is that simasimac with chimes of death, or silent?
My money is on a broken trace. You should open up a new thread to get into more detail and post some pics of the board.

No chimes, just silent. I wish it was a simple as a broken trace, I already would have found it. The board is prisitne with no battery leakage. I've already recapped too. I've even used the simasimac repair guide to tone out all the traces.

 

[croissantking]

No chimes, just silent. I wish it was a simple as a broken trace, I already would have found it. The board is prisitne with no battery leakage. I've already recapped too. I've even used the simasimac repair guide to tone out all the traces.

I could be interested in buying it if you decide that repair isn't feasible for you.

 

[chiptripper]

No chimes, just silent. I wish it was a simple as a broken trace, I already would have found it. The board is prisitne with no battery leakage. I've already recapped too. I've even used the simasimac repair guide to tone out all the traces.

Simasimac can be such a puzzle. I assume since you’ve followed the repair guide that you’ve tested RESET too? And have you tried using serial diagnostics using another 68k Mac or the Reconaissance app?

I’d probe SWIM next and see if it’s functioning as expected or if any pins are stuck low.