3 Replies Latest reply: Sep 23, 2008 6:52 PM by spudnuty
jared_cunfused Level 1 Level 1 (0 points)
Ok, I'm using an imac g4 and the original pro keyboard and mouse that came with it. My mouse is starting to act funny for the first time ever. Every few seconds, the pointer arrow will just stop moving. And after I move the mouse around for a couple seconds, it jumps to some odd far off corner of the screen. And there have been a couple times it would just not work unless I unplugged for a couple seconds. And the worse part is that last night, when it started doing this, my keyboard locked up on me too and I had to manually restart my computer to get anything to work. I don't think there's anything wrong with the connection because the red light on the bottom of the mouse stays on when it does this. Is there a simple answer to this? Because i'm thinking (and dreading) that it's some kind of software problem. I'm just so frustrated. I love my imac and it's never given me any problems. I don't know why it would start now.

iMac G4 17", Mac OS X (10.4.11)
  • spudnuty Level 5 Level 5 (6,155 points)
    Hey Jared,
    The first thing to try is a different keyboard and/or mouse.
    Next try this, from the service manual:
    "Resetting the PMU (Power Management Unit) on the logic board can resolve many system
    problems. Whenever you have a unit that fails to power up, you should follow this procedure
    before replacing any modules.
    1. Disconnect the power cord.
    2. Remove the user access panel from the bottom of the computer.
    3. Press the PMU reset switch (shown below) once on the bottom side of the logic board and then proceed
    to step 3. Do NOT press the PMU reset switch a second time because it could crash the PMU chip.
    4 WAIT ten seconds before connecting the power cord and powering the computer on. If the
    computer powers on, go to the next step. If the computer does not power on, there is something
    else wrong with the computer, refer to the symptom/cure, “No Power” in this chapter.
    5. Run MacTest Pro and return the computer to the customer.
    Note: This entire procedure resets the computer’s PRAM. Be sure to reset the computer’s time,
    date and other system parameter settings before returning the computer to the customer."
    BTW the PMU button us under a rectangular flap of plastic in the user port on the bottom of the iMac. I haven't seen a block diagram on the G4 iMac but the mouse and keyboard are run by the PMU in most other Macs I've seen.
    Richard

    Message was edited by: spudnuty
  • jared_cunfused Level 1 Level 1 (0 points)
    so that would help my keyboard and mouse problem?
  • spudnuty Level 5 Level 5 (6,155 points)
    Jared,
    so that would help my keyboard and mouse problem?

    "The first thing to try is a different keyboard and/or mouse"
    That's going to tell you if your mouse or keyboard is bad.

    "the mouse and keyboard are run by the PMU in most other Macs I've seen."
    So resetting the PMU will correct any problem the PMU is having.

    Also try another USB port and disconnect any other USB devices or peripherals.

    Richard