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and the lights went off..

A

aicul

macrumors 6502a
Original poster
Jun 20, 2007
809
7
no cars, only boats
I hate those washing machines that have a door security. It'll be clear soon. To get the door open I cut the house circuits and put them back on.

Since then my sun flow 20" iMac (Ppc) has stopped working.

Grrr on myself somehow.

Anyway, I'm trying to collect advice on steps to potentially revive this beauty.

Presently it is sitting on my desk half open.

Any technicians out there please suggest (anything non destructive)

thanks
 
A

aicul

macrumors 6502a
Original poster
Jun 20, 2007
809
7
no cars, only boats
Well damn. I guess the first step would be to try a PMU reset.
Click to expand...
I.e. what specifically is its condition now: doesn't boot, doesn't react on power button, can't load the OS or it's deader than a doornail?
Click to expand...

It does not react to power button.

I tried the PMU reset, no success.

I checked the backup battery which is strong at 3.6v+

Looked for obvious burns and failures (all the way to fan which implies a full dismantle), nothing visible.

Would like to test the transformer but not sure where to check this.
 
D

Dane D.

macrumors 6502a
Apr 16, 2004
645
8
ohio
aicul said:
I hate those washing machines that have a door security. It'll be clear soon. To get the door open I cut the house circuits and put them back on.

Since then my sun flow 20" iMac (Ppc) has stopped working.

Grrr on myself somehow.

Anyway, I'm trying to collect advice on steps to potentially revive this beauty.

Presently it is sitting on my desk half open.

Any technicians out there please suggest (anything non destructive)

thanks
Click to expand...

Had this happen to me after a strong thunderstorm knocked the power out. When the power came back on, no chime, no power. The power supply was fried from the surge of electric coming back into it. Was plugged into the wall, not a surge protector strip. Lesson learned the hard way.
 
Swampus

Swampus

macrumors 6502
Jun 20, 2013
396
1
Winterfell
Agree that testing the PSU is the next step. If you have a voltmeter and wish to continue, download this and start with page 14 of the troubleshooting section for instructions. It's pretty straightforward, but please ask if anything is unclear. Set your meter for DC current.
 
A

aicul

macrumors 6502a
Original poster
Jun 20, 2007
809
7
no cars, only boats
Swampus said:
Agree that testing the PSU is the next step. If you have a voltmeter and wish to continue, download this and start with page 14 of the troubleshooting section for instructions. It's pretty straightforward, but please ask if anything is unclear. Set your meter for DC current.
Click to expand...

Hi, I have been using that manual to disassemble the iMac, but it falls short of indicating what to measure to check if the power supply is broken.

I'm supposing a measurement on the cables going to the hard disk or optical drive would be a good start, but would want to make a clear fix of this.

Any experience on this end.

Note: Indeed I should get a surge protector.
 
Swampus

Swampus

macrumors 6502
Jun 20, 2013
396
1
Winterfell
aicul said:
Hi, I have been using that manual to disassemble the iMac, but it falls short of indicating what to measure to check if the power supply is broken.

I'm supposing a measurement on the cables going to the hard disk or optical drive would be a good start, but would want to make a clear fix of this.

Any experience on this end.

Note: Indeed I should get a surge protector.
Click to expand...


You could start with the test holes and measure 12 VSLP against ground. 12 volts here would usually indicate a good power supply.

However, even if you get 12 volts from 12 VSLP to ground, I would still proceed to step 12 in that section. Skip everything in the middle for now. Disconnect the 16 pin power supply connector from the motherboard. Leave it disconnected for a few hours. Sometimes this will actually solve the problem. I don't know why it would be any different than simply leaving the whole computer unplugged for a few hours, but it often turns out to be.
 
M

magilla

macrumors regular
Aug 3, 2013
223
0
Giuly said:
…and invest $13.50 in a surge protector so you don't kill your next Mac, too.
Click to expand...

A $13.50 surge protector likely will NOT give adequate protection against the OP's lightning strike. Everyday normal current surges that happen about 10-12 times a day sure, but not lightning strikes. Why protect a multi-thousand/hundred $$$ system with a less-than $20 piece of hardware?
 
Giuly

Giuly

macrumors 68040
Oct 16, 2009
3,348
4
That depends whether you ask for timezone, state o
magilla said:
A $13.50 surge protector likely will NOT give adequate protection against the OP's lightning strike. Everyday normal current surges that happen about 10-12 times a day sure, but not lightning strikes. Why protect a multi-thousand/hundred $$$ system with a less-than $20 piece of hardware?
Click to expand...

Because Belkin is so confident in the $13 piece of hardware that they give you a "$75.000 connected equipment warranty".

OP also doesn't have problems with lightning strides, but is manually tripping the fuse to open his washing machine.
 
A

aicul

macrumors 6502a
Original poster
Jun 20, 2007
809
7
no cars, only boats
Here I am back. First thanks to all for patience.

I followed the manual instructions page 14 of the trouble shooting guide. This guide is for the 15" sunflower iMac and mine is the 20" so there are a few differences in the figures.

Nonetheless, when checking the power connector (step 12, page 15) I found a small issue. Of the 5 12v points, only 4 where good, the other was 0v.

See power connector figure with dead 12v in red

So my intentions would be to hotwire another of the 12v to the the "dead" pin and see if the iMac wakes. But this manual being for 15" and not the 20", I am uncertain if this will do more harm than good.

Can anyone confirm this is a reasonable approach ?
 
A

aicul

macrumors 6502a
Original poster
Jun 20, 2007
809
7
no cars, only boats
time to smile again

The iMac is back to life :)

The problem was with the transformer. Once I dug it out (ouch that was a long work) I could hear it going Buzzt-Buzzt.

Ordered a new one on eBay and installed it and there we go, the iMac is heart throbbing again.

Whilst I'm at it, the new transformer had the same "dead" pin in the power connector (see my previous post). So I'm thinking this connector image is not for the 20" iMac.

Thanks for everyone for their feedback

----------

And for the record, I also de-activate the door security of my washing machine (see first post)
 
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