IIci PSU - Dead as a Dodo

[Mark (Millennium Macs)]

I recently got my IIci up and running again after a lot of dramas with the CPU getting dinged while I was re-assembling it... then having had that fiasco repaired I then couldn't get video which turned out to by the adapter settings... anyhow the Logic board is seemingly all good now. The final issue I have (which was also stopping the machine starting up) is the PSU (Astec) seems to have died.

Having tested the IIci logic board with a Quadra 650 PSU (Delta Electronics) I found the logic board seems to be fine, and the soft-power works as expected.

I replaced the majority of the PSU caps and reassembled it and it does a great deal of nothing. No +5V Standby at all so it's not even possible to jump-start it.

I am looking for suggestions, locations and possibly photos of where and what to look at for the failures, as although several people have made suggestions I have no idea where the various parts of the PSU are to try and locate some of them.

 

[Garrett]

Step 1 is to check the fuse. If it's blown, I'd be suspect of surrounding components. I had one that blew, but was actually caused by a blown MOSFET, meaning just replacing the fuse would immediately blow it again. Troubleshooting can be tricky, but it's absolutely possible to do with enough patience!

 

[roymaya]

You said you replace the majority but not all? I would replace them all. There's also a cap or two on the little vertical daughterboard the tyou should replace. Oh, and don't forget the Rifas.