10.5.2 combo update - auto sleep no longer works

Question

Since performing this upgrade yesterday, auto sleep no longer functions. The screen saver blanks the screen at the correct time but that's as far as it goes.
I've repaired permissions, tried resetting the Energ Saver defaults, resetting the SMC and deleting the com.apple.PowerManagement.plist file and am no further forward.
Is anyone else experiencing auto sleep issues after the 10.5.2 upgrade?

Answer 1

Okay. I think I've solved auto-sleep. At least for my system. It requires going into to terminal and changing the minutes of 'disksleep'. It's very easy and non-invasive. First check your pmset settings in termnal by typing: pmset -g
You should see something like this:
Active Profiles:
Battery Power -1
AC Power -1*
Currently in use:
sleep 10
sms 1
displaysleep 5
hibernatefile /var/vm/sleepimage
halfdim 1
lidwake 1
ttyskeepawake 1
acwake 0
autorestart 0
hibernatemode 3
Hibernate Free Ratio 5
womp 0
disksleep 12
First, you want to be sure your hibernatemode is set at 3 (the default in Leopard). If it isn't you can change it by typing: sudo pmset -a hibernatemode 3
This is the command that you will now use to change what I think fixes auto-sleep. If you notice 'sleep' and 'displaysleep' are set at the minutes you have set them at in your Energy Preferences (5 and 10 in my example above). You can just leave these settings. 'Disksleep' is the command that should tell your computer to hibernate (auto-sleep) and it is by default set at whatever your 'sleep' setting is. What I did was change 'disksleep' to 12 (again the command in terminal for this would be: sudo pmset -a disksleep 12).
My theory is that by seperating the 'disksleep' setting from the 'sleep' setting by a couple of minutes, the command to hibernate is somehow stronger or clearer. At any rate it worked for me when nothing else would. If for some reason the computer doesn't hibernate at exactly 12 minutes, give it an hour and see if it does sleep in that time. You can test this with AC power and then with battery. Sometimes the AC is easier to get auto-sleep working for some reason.
If you want to save your pmset settings just copy your pmset -g query in a text file and you can revert to whatever your default was by then using the sudo pmset -a command.
The first step before you change the pmset settings is to make sure that no third party software is keeping your system awake. Console activity should display that, whether it's a program or a widget. Obviously you need to either uninstall or deactivate the offending program or widget before moving forward. Also make sure you've completely followed all the previous suggestions for troubleshooting lack of auto-sleep (pmu, pram, safe mode resetting... de-selecting preferences (for example: uncheck all boxes in advanced settings for Bluetooth if you use bluetooth devices or uncheck Wake for Ethernet network administrator access in Energy Preferences Adaptor Options).
Hope this helps someone else. I've been struggling with this issue since leopard came out. And through trial and error worked my way up to this. Let me know if it works for you.