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Please help, don't mess around with J16 on a iisi

jajan547

Well-known member
Hello everyone I was hoping someone here could help me figure this out. So if you look at J16 on a iisi it is unused I figured that maybe I could use it as a more reliable means for other speakers because it shared continuity with the same pins as the speaker/led contacts underneath the board. well I thought I had hooked everything up correctly and well I got a click noise from the speaker and the LED works but I got either no image or a blue screen, also I had no distinct sad Mac or normal Mac booting noises. However, the iisi turns on and the fans spin, and the floppy drive works, and even the SCSI HDD spins up and runs. But then again no picture, no sound nothing. I have tried everything and yes the capacitors are okay. I even tried diagnosing issues with my TechStep. I didn't look at the schematics before I did this but I have included the schematics for the iisi below and the configuration I used to test J16. Any help is greatly appreciated! I have a video of what happens as well.


(Cross-posted from TinkerDifferent)
 

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Byrd

Well-known member
Hi,

have you done the basics - pull PRAM battery, reset PRAM, strip out all RAM, checked PSU voltages? Good luck!
 

jajan547

Well-known member
Hi,

have you done the basics - pull PRAM battery, reset PRAM, strip out all RAM, checked PSU voltages? Good luck!
I've done all and everything checks out two strange things to note though with a a jumper on W1 it sometimes (1/13 chance) will make a sad mac noise but this is only with the jumper. Also when I use a floppy emu it gives me the lock icon and it won't even attempt to boot from say a startup disk or disk tools image.
 

volvo242gt

Well-known member
Sounds a bit like when I blew the SCSI bus on my first IIsi, which had an unreliable fan connection, in addiion to the audio/power LED issues that frequently afflict these machines.

Might be a good idea to find a good working board, then work on this one as a project. If it can be fixed, then you'd have a spare.

-J
 

jajan547

Well-known member
Sounds a bit like when I blew the SCSI bus on my first IIsi, which had an unreliable fan connection, in addiion to the audio/power LED issues that frequently afflict these machines.

Might be a good idea to find a good working board, then work on this one as a project. If it can be fixed, then you'd have a spare.

-J
But what’s weird is I don’t think any of what I connected goes to that I have four working board and two spare parts boards.
 
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