Thanks Dan, wish I'd known about the voltmeter test not being much use which I'd assume means that this is my last demand before deciding that I'm physically unable to figure out a thing because I'd surely have thought that the weak battery would at least be able to make a credible start, even if it fizzled. But then again, you weren't involved in this discussion in the beginning so I'm guessing that the idea that 'under load' results is not what we are seeing.
Then again, it's vitally important to check these things out and I shall be doing that somehow or other once I get the machine back. Don't you agree that your own ideas are getting tired of paying through the nose so that we can just follow orders of some expert who doesn't do things like he tells you to do them before you decide to try his expertise once your own testing at his instruction does fail...??
For example, EVERY instruction page, online or in print, says not to open the box until you've pulled the plug out of the wall and made certain that the power is off... Don't you agree? So why was it that the high-priced tech that I trusted to get me my answer once the power supply idea turned sour, was telling me over the phone later that he was seeing those legendary clicks as sparking on the motherboard as he was working on the G4 (my iMac is permanently retired unless I can't use my son's G4 once we get this power-up problem solved. Obviously, that sparking means he had the box open, the power turned on and was sitting there scanning the surfaces and noting any source of sparking. Amazing revelation. Don't follow orders, just do what seems sensible. Like looking for the muffled-tiny-crackling noises that you can't see with the box closed, just be sensibly careful...
I'd assume that the PMU is the cuda button, which we did try, a couple of times, before and after the new power supply unit (guaranteed to be functional) was installed. Want an extra power supply module..?
BTW what's the difference between the interior cuda and that button on the outside of the G4 that's right alongside and below the power-on button... that's the one I was using in the past to jolt the G4 out of some lock-up in the software, and it would be able to re-boot when there was no response from any other quit/shut-down/interrupt option on the keyboard/mouse? I thought it was called the cuda, sort of like that other strange indented button on the side of the iMac near the USB port, which sort of did the same rescue thing... Don't you agree that these things are symptomatic of experts knowing that their systems/programs are not really possible to be debugged thoroughly? Agreed?
As for the motherboard, I'd wonder just what ideas you have on where to go to get such a vitally needed item which is trustworthily decently refurbished, assuming that's better than just used but functional, or is that the case? Use but functional is better? Sort of like medical patients being given the green light as 'good as new' when they would have been healthier to never have been sick... puzzling complications, don't you agree?
Yeah all the peripherals were pulled just so we could get the machine someplace safe and static-free and that made a better working place... what sort of internal peripherals would there be in a G4, maybe an internal modem? Don't know what that would do to make the machine cease to respond to the power-on button..? Ditto for the memory, though it's an interesting protocol to remember, thanks.
TIA
MJ Raichyk
Mount Orab, OH
------------------------------------------------
Dan
Sun, May 6, 2012 at 10:40 PM
Reply-To: [email protected]
To: [email protected]
At 9:37 PM -0400 5/6/2012, [email protected] wrote:
Well the new power supply didn't do it. The G4 just sits quietly and
just makes a faint clicking noise a few times or so til I turn it off.
Haven't really been following this thread, and don't know exactly what iMac you have, but....
Did you replace the PRAM battery? Physically replace it with a new one. Don't just check its voltage - quite often lithium cells give good voltage readings, but they're actually so weak they can't carry the load.
Then reset the PMU.
Must be the motherboard.
Perhaps. Or it could be the Power Manager needs rebooting (see above).
Also... Have you disconnected all the peripherals, both internal and external, and pulled the memory? The idea is to boot the stripped down machine and see if you can get proper error beeps out of the self-test run by the PMU. Once you get that much, start plugging things in one at a time.
- Dan.
--
- Psychoceramic Emeritus; South Jersey, USA, Earth.
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