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Severed Hand of Skywalker · May 25, 2003, 09:30 PM

Two days ago for no reason at all when I my computer goes to sleep it will not wake up. It is also not really sleeping as the button does not pulse but the screen shuts off.

I tried to fix the problem by:

1) Removing the none default fonts.
2) Running a permissions repair
3) Running Disk Warrior 3 (no problems found)
4) Making sure no statup apps launch
5) Running all cron scrips
6) Running fsck disk
7) Zapping the PRAM
8) Running top to see if any NEW background apps are running
9) Logging into another account to see if the problem still happends (it does)
10) Tried to put the computer to sleep at the login screen... the problem is still there.

So I booted into safe mode and everything is fine.

My question is what do you think the problem could be and what exactly does safe mode shut off?

Shaddim · 10:21 PM

Sounds like your Power Manager is corrupted, zapping your PRAM by holding down CMND+OPT+P+R probably won't help. What kind of system are we talking about here? If it's a G4 PM then unplug it from the wall and take out the PRAM battery and your system RAM and let your system sit for 10-15 minutes. Then put your battery and RAM back in and reset the PRAM on the logic board, there's a small reset button located somewhere near your battery, press the button once for less than a second... only press it once. Then plug the system back in and start it up. This will completely restore the logic board back to factory defaults (although firmware upgrades will remain intact).

BTW, after doing this you'll have to set your clock, personal Energy Saver prefs, etc.

In answer to your question. Safe mode will boot your Mac up with the bare minimum of drivers and devices, this includes any custom Power Manager (Energy Saver) settings.

Severed Hand of Skywalker · May 25, 2003, 10:22 PM

I have a G4 Cube.

Would safe mode get around the PowerManager though?

I did Zap the PRAM but just by the key command at startup. IS there another way to do it without having to take out the battery?

Shaddim · May 25, 2003, 10:44 PM

Safe mode will bypass custom PM settings, yes.

Pulling the battery and RAM and hard resetting the PRAM is the only way that I know of. Maybe there's another way but I've never heard of it.

Severed Hand of Skywalker · May 25, 2003, 10:45 PM

Darn, I will try it then.

Apple said that going into open Firmware and typing

"reset-nvram"
and
"Reset-all"

should do the same thing. I will try both.

Shaddim · May 25, 2003, 10:56 PM

Yep, try "reset=nvram" and "reset=all" first and see if that works, if not, try the other way. "Hard" resetting the PRAM/PM is just more "punchy"/powerful.

Severed Hand of Skywalker · May 25, 2003, 11:07 PM

Wow great.

It seems the reset-nvram part did it!

I would have thought that Command option P R would have been good enough but I guess not.

Thanks for your help guys, it saved me the trouble of reinstalling the OS which would have been my next step.

This was very educational.

Shaddim · May 25, 2003, 11:12 PM

There are definitely different degrees of "reset"... also keep an eye out for other strange occurences, your PRAM battery may be on it's last legs. Not a big deal though, they're pretty cheap, <$15.