LC III Dyna Corp PSU - 0V = bad C9

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coisasdavida

New Tinkerer
Feb 2, 2026
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Recently given to me was a Performa 450/ LC III plus a Performa Monitor.
Monitor is fine.
Performa is completely dead.
I removed the PRAM battery. Tried to simulate a charged one and shorted pins 2 and 4 on the ADB port, nothing.
Unplugged floppy, HD, same.
Checked PSU and I measure no voltage on it from any of the colored wires.
It is a Dyna Corp PSU.
I check board and inside PSU, no blown caps, no caps with powdery or liquid residue.

I read posts here:
LC III Dyna Corp PSU not playing ball even after a recap
and
Macintosh LC 475-recap PSU Dyna Comp DCF 353 (apple part No-614-0028}

Have two questions:
a PSU in need of a recap would behave like this? Or would is show incorrect voltages?
or better yet, should I recap it? (have caps and enough experience with soldering)
 
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