Advice on dead PowerBook G4

Discussion in 'PowerPC Macs' started by mccjim12, Sep 23, 2012.

  1. macrumors member


    New to the forums and hoping for a little bit of advice.

    I've had my PB G4 for eight years and in recent months, it started to show symptoms of HD failure...clicking, weird GUI behavior. Anyway, finally, it would not boot and I got the 'you need to restart your computer' message.

    So I figure, ok , I'll just replace the HD. While it was on order decided to try starting it up. Nothing. No lights, no press the power button and nothing at all happens. The light on the AC adapter stays green all the time as well. I've tried all of the PMU/PRAM/whatever it's called resets to no avail and tried a new PRAM battery. I've also tried removing and reseating the RAM.

    Do you guys think the logic board is bad? It just seems like such a strange coincidence since the HD went also.

    I'm all set to find another logic board but wanted to check here first. I'm really not super knowledgeable about these machines as far as hardware. Basically learning as I go.

    Thanks much in advance.

  2. macrumors 68040


    Do all of the above with the battery in and out. A bad hd would just show as a question mark folder, it would still start up.

    I've found with my Powerbook that keeping it plugged in all the time helps. There is an onboard battery somewhere that I'm sure dies after so many years.
  3. macrumors member


    Thanks much for the reply. I actually did replace the onboard battery, to no avail, so it appears the logic board has indeed failed.

    Now I'm torn on actually putting down the cash for a new one. ;) Thanks again!

  4. macrumors 68040


    What Powerbook logic board do you need?
  5. mccjim12, Sep 23, 2012
    Last edited: Sep 23, 2012

    macrumors member

    Mine is 1.5 ghz (15 inch..don't know if that matters)
  6. macrumors 68040


    It could be bad DC in board, esp. if battery is dead or discharged. If battery is OK, then logic board is most likely the culprit.
  7. mccjim12, Sep 23, 2012
    Last edited: Sep 23, 2012

    macrumors member

    Thanks, I did think of that as well. I'm betting against that given all of the other symptoms I had before the no powering on problem. Also, when you plug the AC adapter into the computer without wall power, the light comes on green and stays on. Not so with the battery removed. So it appears the battery has some juice. Weird for sure.

    I'm going to sing when this thing is back online!

    Thanks again!


    EDIT: Uh oh, just noticed none of the LEDs on the battery come on when I push to test. Maybe it is toast...
  8. macrumors member

    UPDATE - Sep 26

    Ok, some progress..

    I put in a new (used) logic board and now the machine chimes and you hear the fan...but then nothing. The screen does not come on and the HD does not sound like it in spinning.

    There seems to be some thought looking around online that the PRAM battery is dead and leaving it on the charger overnight with the main battery removed might remedy this. Any of you guys concur with that?

    Thanks again to everyone for their help. This is my first time working on an Apple machine and it hasn't been all that pleasant. :)

  9. macrumors 68040


    Try it, though usually when the fan spins up it means it is about to boot. I know with my final revision Powerbook, I need to leave it plugged in after long periods of inactivity.

    Are you sure the video card on the new board is working, btw?
  10. macrumors member

    Hmm...not sure. Bought it guaranteed to work so I assumed so. I suppose I could hook up an external monitor to check.

    I will post an update. Thanks again.

  11. mccjim12, Sep 27, 2012
    Last edited: Sep 27, 2012

    macrumors member


    OH MY GOD....

    I don't know how or why, but it's working. Trying to format and install and some of the keys now don't work. Great.
  12. macrumors 68040



    You did the hold down the power button until you hear the three beeps on start up?
  13. macrumors member

    I didn't do that, it seems to be running fine now, except for the problem I'll get to. I fixed the keyboard issue. The cable connector on the board was loose but I was able to get it to hold well enough.

    The issue now is that the screen only comes on intermittently. It starts up but the screen remains black. If you give it a ctrl+cmd+power button reset, sometimes it will come on. Sometimes it takes 2 or 3 of these.

    Sound like a bad GPU?

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