iMac G3 Not Powering On.

[Goftrey]

I have used my Rev.A Bondi-Blue iMac for a good while now solely as a jukebox. It's been doing the same task flawlessly for months, day in, day out - until today.

When the power cable is connected to the iMac, the computer (haven't located where abouts the noise is coming from) makes a very high pitched, tinnitus-like noise. Then, when I push the power button in - the noise becomes louder.

I tried to record both a video & audio sample but the mic. just won't pick up the sound.

There's no startup chime, fans, display. Nothing.

Any ideas?

 

[justperry]

Sounds like a bad capacitor, probably in the power supply.

 

[Lil Chillbil]

Sounds like a bad capacitor, probably in the power supply.

backing up justperry it does sound like a capacitor

 

[Goftrey]

I finally got around to opening the iMac up & diagnosing the issues & it looks like you guys were right. A couple of leaking caps on the PSU board.

 

[Intell]

Those black things with the yellow tops aren't capacitors, those are transformers. They're supposed to have that gunk on them. They extremely rarely go bad. The only ones that I know of going bad under normal use are the flyback ones.

 

[Goftrey]

Those black things with the yellow tops aren't capacitors, those are transformers. They're supposed to have that gunk on them. They extremely rarely go bad. The only ones that I know of going bad under normal use are the flyback ones.

Oh! Well that's good news I guess.

If it's not caps then what on earth could the issue be?

 

[Intell]

I would suggest replacing the power supply with a known good one or even all of its capacitors. Just make sure you get the right revision power supply. The tray loaders had two different power supply revisions.

 

[Goftrey]

I would suggest replacing the power supply with a known good one or even all of its capacitors. Just make sure you get the right revision power supply. The tray loaders had two different power supply revisions.

Just had a quick look around & it doesn't seem economical to buy the power supply as a part when you go & buy a fully working one for the same price or even cheaper.

Guess I'll do something funky with it in the future. Thanks for the help

 

[MisterKeeks]

Just had a quick look around & it doesn't seem economical to buy the power supply as a part when you go & buy a fully working one for the same price or even cheaper.

Guess I'll do something funky with it in the future. Thanks for the help

If you have a multimeter handy I would try seeing if you can get any power out of the power supply.

You might be able to get a very low wattage power supply and use it instead. I believe that the G3s had an 80 watt PSU.