# G5 Random Shut Down



## Dan B (Aug 4, 2008)

I have a G5, dual processor machine. It randomly decides I want it to shut down, flashing the dialog box, "Are you sure you want to shut your computer down" with the buttons for Restart, Sleep, Cancel and Shut down. Has anybody experienced this? Could it be a RAM problem? It is very annoying. In fact it just popped up while typing this. If I happen to be about to hit Enter for any reason as it pops up, I get caught, and it shuts down on me.
I have replaced the hard drive, but that had no effect.

Ideas?

Thanks!


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## macthorough (Jul 5, 2008)

Is you power button stuck? Run your apple hardware test cd in looping mode.


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## sinclair_tm (Mar 11, 2005)

THe window that comes up with a choice only comes up if the power button is pushed on the keyboard, and depending on the Mac, if the power button on the case is pushed. If your keyboard has a power button, check to make sure that it isn't stuck down, or shas some dirt in it that may be causing a momentary contact. If there isn't a power key, then there is something wrong with the button on the case. I believe that if you open the System Preferences and goto the Energy Saver pref pane, there will be an option in there for the behavor of the power button. You should be able to tell the OS to ignore the button. But if the button is stuck, it may singal pushed long enough for the PSU to see it and just turn the computer off without any warning.


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## Dan B (Aug 4, 2008)

OK. I ran the hardware test overnight last night. So far, I have not had the random shut down. I switched out the keyboards earlier, so that rules that possibility out, leaving the power button on the case as the likely culprit. The only option on the Energy Saver preference pane I see that relates to the power button is one allowing it to sleep the computer. I unchecked that box. Another interesting aside...sometimes the little sun icon (brightness) comes up on the monitor randomly too.. related?


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## macthorough (Jul 5, 2008)

Reset your PMU or SMU which ever you have! That will set the energy saver setting to default which will clear any energy saver issues.


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## sinclair_tm (Mar 11, 2005)

That sun icon comes up when the computer recieves an adjust brightness command, which can also be done from the keyboard, as well as the monitor. What monitor do you have? Also, go into the keyboard pref pane and look to see what keyboard shortcuts are turned on. It could be that some non-standard shortcuts are active and you are hitting them without knowing.


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