G4 won't startup but ticking sound in power supply area when plugged in

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G4 won't startup but ticking sound in power supply area when plugged in

My G4 had been fine since the HD went bad years ago and was replaced.
Didn't use it much for a while, then would start normally but shut down with no warning after a few minutes. Then after seconds, then power btn would light up but shut down immediately.
Replaced battery and pushed PMU button. (button doesn't seem to react in any way so don't know if pushed properly or not)
Then nothing happens at all when I push the startup button. But I noticed a quiet ticking sound coming from the area of the power supply, and remembered I had heard that noise lately not knowing where it came from (when it's plugged in but not on). It has always been plugged to a APC BACKUPS 500.
Put back old battery and no difference.
I hope the power supply is not dead, probably cost more than a G4 to replace it.
Any clues? Thanks

G4 Quicksilver 867, Mac OS X (10.3.x), OS 9 on other partition

Posted on Feb 18, 2011 2:46 PM

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Answer 1

Feb 26, 2011 4:27 PM in response to chasmania

Take a look at these active threads, on this forum:
"FW800 - Unplug Power & Plug in to Start up" threadID=2734178
"Power Mac G4 has power issues" threadID=2754949

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Answer 2

BDAqua

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Feb 26, 2011 4:43 PM in response to Al Cellier

http://discussions.apple.com/thread.jspa?threadID=2734178&tstart=0

http://discussions.apple.com/thread.jspa?threadID=2754949&tstart=0

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Answer 3

chasmania Author

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Mar 3, 2011 2:41 AM in response to BDAqua

Thanks for your responses,
my 867 Quicksilver 2001 is not like the MDD macs I see in these posts.
I have left it unplugged since I posted the question because the ticking sound when plugged in makes me nervous - doesn't sound as regular as a time bomb but scary. It had started once in a while, then more and last I checked with various power chords and outlets, it was constant.
The machine doesn't react in any way to the power button at this point.

I saw somewhere on the forum a way to push the on button for a 5 count then take out the battery and unplug and wait and then I can't remember the rest... Based on the symptoms I've described, do you have a recommendation for next step?
Thanks!

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Answer 4

chasmania Author

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Mar 3, 2011 2:43 AM in response to chasmania

Oops, when I wrote "it had started once in a while..." I meant the ticking sound had started, not the computer.

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Answer 5

BDAqua

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Mar 3, 2011 3:47 AM in response to chasmania

I saw somewhere on the forum a way to push the on button for a 5 count then take out the battery and unplug and wait and then I can't remember the rest...

I think you might mean a PMU/SMU reset.

How to reset the SMU/PMU on a Power Mac Earlier G3, G4, G5 models...

http://support.apple.com/kb/HT1939

do you have a recommendation for next step?

Offhand, it sounds like the Power Supply is bad.

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Answer 6

chasmania Author

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Mar 10, 2011 9:06 AM in response to BDAqua

Thanks, sorry I had to concentrate on urgent work problems and didn't see this right away.

I'm afraid you are right that the Power Supply is bad. I haven't had any luck with the PMU reset. I will try again and post the result here...

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Answer 7

chasmania Author

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Apr 5, 2011 8:26 AM in response to chasmania

OK, I found the info I was looking for on the forum, which was:
"Disconnect all external devices/cables/cords except the power cord.
Touch a metal slot cover on the back of the Mac as a static electricity discharge precaution.
Remove the battery.
Reset the PMU, depressing the button for a five-count.
Depress the front power button, again for a five count.
Wait 30 minutes or so to insure the capacitors on the logic board are fully discharged.
Reinsert the battery.
Reconnect the power cord, mouse, keyboard, and monitor and attempt startup."

After doing this, the power button did light up! 🙂 BUT went out immediately 😟
Same thing several tries.
Also when I plugged it in after the 30 min without battery, there was the ticking sound for a few seconds, but then stopped. Hmm. ?

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Answer 8

BDAqua

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Apr 5, 2011 12:17 PM in response to chasmania

Here's info on your Mac...

http://www.everymac.com/systems/apple/powermacg4/stats/powermac_g4_867qs.html

If it is the PSU, you can convert a cheap ATX PSU...

http://atxg4.com/quicksilver.html

http://atxg4.com/

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Answer 9

chasmania Author

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Apr 5, 2011 1:52 PM in response to BDAqua

Thanks for the info.

So it looks like it must be the PSU?

I am not qualified to do the kind of wiring, adapting for the ATX PSU. Might be possible for a friend I can ask. Certainly would be much less cost than the PSUs on ebay...

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Answer 10

BDAqua

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Apr 5, 2011 2:13 PM in response to chasmania

It's tough to tell out here, but it does sound like the PSU.

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Answer 11

chasmania Author

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Apr 5, 2011 3:05 PM in response to BDAqua

Thanks for your help. I'll see what I can do on the PSU...

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Answer 12

chasmania Author

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Nov 14, 2011 6:28 AM in response to BDAqua

I let the G4 sit unplugged months (with the new battery).

Then I tried a last ditch idea, picking it up and shaking it in all directions. (saw someone's post that this had worked!) Then plugged it in and no more ticking sound.

Then after a few days, tried and it started up! It would shut right down if monitor plugged in.

Every day for the last 2 weeks, I start it up with nothing connected. It would run for 2 minutes, then up to 3 minutes, but for the last 2 days only 1.5 minutes, before shutting down.

Is there a next step to get it up and running? or is this all I can hope for?

Thanks for any info

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Answer 13

BDAqua

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Nov 14, 2011 9:57 AM in response to chasmania

Have you pulled & reseated the Video card, RAM, and any other cards?

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Answer 14

chasmania Author

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Nov 15, 2011 2:12 AM in response to BDAqua

No, I will try that and let you know. Thanks

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Answer 15

chasmania Author

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Nov 15, 2011 4:04 AM in response to BDAqua

I pulled & reseated the Video card and RAM cards. (unplugged mac while open)

Plugged in and connected monitor and keyboard, now power button only lights up while I'm pushing it, then nothing. Before I was getting the startup sound and all normal startup. Now nothing also with no monitor or keyboard connected.

Might not have reseated something correctly?...

I will wait a while and try again with no monitor as before...

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