PowerBook Duo 250 death chimes

[james_w]

Hi all. I recently acquired a PB Duo 250. It had to sit in a drawer for a few months before I could get to it, partly because all my PSUs for Duos are in storage.

I now have a working PSU but on boot all I get are death chimes. Apple service manual says this is a memory issue... and to replace the logic board. Obviously I would prefer to rescue this board rather than do that.

It also has no video showing on the display.

I replaced all the electrolytic caps and gave the board's top and bottom a general clean with IPA but still the same issue.

I've also tried booting with and without an add-on memory board.

Any ideas?

Should I deep clean the board?

Should I replace caps in the screen?

Could it be an old PSU causing the issue by not supplying the right voltage/current? (I can test this easily)

Any ICs or other components I should be checking?

 

[Papichulo]

Is the battery removed? It could be the adapter also 

 

[james_w]

It's not got a main battery nor a back up (PRAM) battery installed.

I'll give the PSU a test this evening

 

[Papichulo]

Its probably the adapter