Mac won't start up...

Discussion in 'PowerPC Macs' started by mamlukman, May 15, 2018.

  1. mamlukman macrumors newbie

    Joined:
    Nov 5, 2013
    #1
    I went on a short vacation and so I unplugged all my computers, the modem, and the phone line to the modem.

    My backup computer is a G4 Mirrored Door Drive. I've never had any issues with it. But this time it won't start up: It gives a 2-second "whirrrrr....." and then nothing.

    I fear the worst, but any thoughts?
     
  2. macuser453787 macrumors 6502a

    Joined:
    May 19, 2012
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    #2
    It might be that the PRAM battery needs to be replaced. A similar thing happened to me many years ago with my G4 Digital Audio.

    You can try replacing it with a 3.6V lithium PRAM battery like this one and see if that works.

    Incidentally, your question is a topic for the PowerPC Macs forum instead of the Mac Pro forum. :)
     
  3. mamlukman thread starter macrumors newbie

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    Nov 5, 2013
    #3
    Good idea. It's been so long that I've changed the battery I didn't even think of it. I've ordered one. Hope it works.

    As for the forum, the only choices I saw were "mac Mini" "Mac Pro" and something else...but NOT Power PC. Maybe they're got categories in several places. I've always found this forum hard to use!
     
  4. macuser453787, May 15, 2018
    Last edited by a moderator: May 15, 2018

    macuser453787 macrumors 6502a

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  5. Roman78 macrumors member

    Roman78

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    #5
    The MDD should start with the battery removed.

    It could be the power supply.
     
  6. chscag macrumors 68030

    chscag

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    Fort Worth, Texas
    #6
    That's exactly what he was told in the "other" Mac Forum he posted the same thread to. Guess he didn't trust what he was told there. o_O
     
  7. Roman78 macrumors member

    Roman78

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    #7
    Once... a long time ago... i converted a normal ATX power supply into the MDD. Modified it so that it even fits into the original power supply cage.
     
  8. AphoticD macrumors 68000

    AphoticD

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    Feb 17, 2017
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    Australia
    #8
    There are pin out diagrams and instructions for using an ATX PSU in the G4s at http://atxg4.com/

    Given a bit of patience, it should be easy enough to adapt. Just be aware that the GPU will no longer be able to power the ADC port for an Apple Cinema Display.
     
  9. macuser453787 macrumors 6502a

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    #9
    When a similar issue happened with my DA G4, it wouldn't power up until I replaced the PRAM battery. Before I did that, the power light on the front would fluctuate on and off and the fan would run, but no power up.

    Possibly. I suggested the PRAM battery because the OP mentioned unplugging the computer for a while, which could have caused a drain on the PRAM battery especially since it had been so long since it was replaced.

    Some years back I found that website, looking for a way to use a standard ATX power supply with my DA G4. This guy wasn't making the adapters at the time, but when I asked him he made one for me. He was really nice about it and the product worked perfectly. :)
     
  10. eyoungren macrumors Core

    eyoungren

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    #10
    Why do it yourself when the same website will sell it to you by model? ;)

    http://atxg4.com/order.html
     
  11. macuser453787 macrumors 6502a

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    #11
    Exactly. He's in business again. Why not? :)
     
  12. mamlukman thread starter macrumors newbie

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    Nov 5, 2013
    #12
    I replaced the PRAM battery with a new one--no difference. The power button lights up for a fraction of a second, then goes dark. Also a fraction of a second of noise from inside. I guess the next step is the power supply. I do have an identical (?) MDD G4 that I kept for "parts" and I will take the power supply from that and see what happens.

    And yes, if I have an issue, I do post it on a couple different web sites--it's not that I don't "trust" one over the other, I simply assume different people might look at different ones!
     
  13. mamlukman thread starter macrumors newbie

    Joined:
    Nov 5, 2013
    #13
    OK, it's working--I had already replace the PRAM battery, bushed the PMU button, etc. with no change. Luckily I had a duplicate G4 just in case I found myself in this situation. After watching a couple Youtube videos, I tested the "spare" computer. It started up. So I removed the power supply and put it into the "good" computer. Now it works fine. So it was the power supply.

    I'll add a suggestion to those who make videos: it took me two days and probably 6-7 hours to do this, and Ive drew blood about 4-5 places. Why? Because the videos assume you know stuff--and if I knew stuff, I wouldn't have to watch the video!!! Like what? Well, screws are pretty obvious. Getting to them is another matter. Then there are always some sort of hooks/brackets on the back of all the cages, power supply, etc. etc. Which way to they go? Do you push up, left, right, or down to release them from the hooks/brackets? On on the drive cages there is a white lever you have to push to release them. None of the videos dealt with any of this, so it took me forever with trial and error. Yes, if you replace power supplies or drives every day it's "obvious," but someone like me who deals with this sort of thing every 5-6 years is clueless. PLEASE--if you make a video, make it for people like me!


    .
     
  14. eyoungren macrumors Core

    eyoungren

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    #14
    Videos are not always the best thing. I've had to use one from time to time, but it's never my first resort.

    I usually go here: ifixit.com

    In your case, with your Mac, this was a covered guide: https://www.ifixit.com/Guide/Power+Mac+G4+MDD+Power+Supply+Replacement/1622
     
  15. Brains macrumors newbie

    Brains

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    #15
    Five gets you tuppence the faulty PSU was an AcBel :)
     
  16. RhianB macrumors 6502a

    RhianB

    Joined:
    Sep 3, 2016
    Location:
    505 USA
    #16
    My acbel psu on my dual 2ghz pmg5 failed & had to be replaced. I did take the time to scavenge the fans & some other random bits off it though. Glad you got yours fixed :)
     

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