PowerBook Goes to Sleep Randomly

[Jay42]

I have a 1.5 year old G4 PowerBook (1.5ghz, 512mb ram, running 10.4.8) that has been going to sleep randomly. The screen will turn black even while I am using the mouse or typing on the keyboard and then it goes to sleep and the light pulses. Yes, I have checked my power settings, and the computer is set to never go to sleep.

I cannot figure out what is causing this to happen. At first I though it might be a heat issue, but I don't think thats the case since it goes to sleep rather than shutting down completely and the computer does not feel warmer than usual.

If anyone has any experience or thoughts on this issue, I would greatly appreciate any advice, thanks.

 

[gameguy3001]

One thing I can suggest that you try is reset your computers Power Management Unit and the steps are on the Apple Knowledge Base depending on the model of powerbook you have. You can also try removing the prefrence file for the PMU.
hard drive>Library>Prefrences>SystemConfiguration>com.apple.powermanagment.plist

 

[Jay42]

Excellent, I will see if this works. Other advice is still appreciated.

 

[yg17]

Excellent, I will see if this works. Other advice is still appreciated.

I had the same problem. Turns out it was a temperature problem, well, sort of. I had a faulty temp sensor, and it thought that my PowerBook was overheating when it really wasn't. According to the genius at the Apple Store, PowerBooks do sleep rather than shutdown when they overheat to save your data. The sensors would randomly throw extremely high temps. I think one of the temps it read was 266 Fahrenheit which caused it to sleep. Apple sent it off for repair and replaced some stuff and my PowerBook hasn't done it since.

To check if that's the case, go to Applications/Utilities/Console.app. From the File menu, choose Open System Log. Look for the time when your PowerBook went to sleep, and if it is "overheating" there should be an entry in there that says something like "Emergency Overtemp, going to sleep"

 

[Jay42]

Yep, it is a heat problem. Or at least a sensor problem. There were several entries in the system log for "Power Management has received an emergency overtemp signal."


I am out of my Apple warrantee and do not have Apple care . Does anyone have an idea how much repairs might cost from Apple.