Reset power management unit (PMU) 12" PB Aliminium case

The Apple instructions for resetting the PMU are:
1. If the computer is on, turn it off.
2. Reset the power manager by simultaneously pressing and then releasing Shift-Control-Option-Power on the keyboard. Do not press the fn (Function) key while using this combination of keystrokes.
3. Wait 5 seconds.
4. Press the Power button to restart the computer.
I've followed the instructions and can't get the PMU to reset. (I understand that the date and time resets when the PMU resets thereby giving you an indication that it has been successful).
I must be doing something wrong though the instructions seem quite clear.
Is there a trick that I'm missing?
How long should I hold the'Shift-Control-Option-Power' keys down before I release them?
Grateful for any help or direction.

When you press the correct keys it works a treat. Problem solved.

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Reset G4 Quicksilver Power management unit

Powerbook G4 Mac OS X (10.4.3)
My G4 won't start. It may be the Power Management Unit. I want to rest the PMU. I can find nothing on resetting the power management unit on a Quicksliver desktop G4.
Any suggestions?
Jay Leonhart

I am having similar problems looking for the quicksilver pmu instructions, but these should be close.
http://docs.info.apple.com/article.html?artnum=95037
there is a lengthy discussion of it here as well
http://forums.macosxhints.com/archive/index.php/t-28650.html

Resetting the Power management unit

I have a 12" Powerbook G4. have been having problems with the battery, would charge fully, with coconut battery, would show 4081 as current battery capacity.
It would drain down to around 79% then immediately go to sleep and when plugged in, battery would show 0%.
I want to reset the power management unit, and see if this might solve the problem.
I've followed the instructions
shift-ctrl-option-pwr button
After I do that (I've done it with the power cord connected, with it disconnected, and with it disconnected, and the battery disconnected). The time doesn't reset. I had thought that the time was supposed to get reset. Can anybody confirm that this? is there any way to know that the powermanagement unit has actually been reset?
Just want to try a few last things before spending the money on a new battery. btw, the computer is about 3 years old.
Thanks.

This line:
Full charge capacity (mAh): 5893
and this one:
Cycle count: 60
indicate that the battery is healthy. However, the voltage, at 15961, seems high. However I can't compare to my PB17 right now because my daughter borrowed it.
Maybe someone who has their PB handy can compare their numbers.
If the battery is healthy and the a/c adaptor seems to be working, that leaves the internal power circuitry as a suspect.

How do I reset the power management unit on a Mac Pro laptop?

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Hi,
We have about 10 PowerBook G3 Firewire computers at our school. They haven't been used in a couple of years and now none of them will start up when I press the power button. I went to Apple's support pages and was told to press the reset button the back, wait 5 seconds and then press the power button. I did this but nothing happened. Does anyone have any suggestions?

While there could be a variety of reasons the PowerBooks do not start up a very common one, especially when the PowerBook has sat idle and unplugged for a long time, is the depletion of the pram battery. For some reason a dead pram battery will prevent the PowerBook from starting.
First try leaving the PowerBook plugged into it's power adapter overnight and see if it starts the following day. If that doesn't work you can take the keyboard off and disconnect the pram battery. A PowerBook G3 Firewire (Pismo) can start and run without the pram battery. It will forget it's time and other settings if you unplug it though.
Here are instructions for disconnecting the pram battery:
http://www.ifixit.com/Guide/Repair/Installing-PowerBook-G3-Pismo-PRAM-Battery/21 /1
Note: You do not have to disconnect the ribbon cable for the keyboard in this process. Just lay the keyboard upside down over the track pad and leave its cable pugged in. Once the keyboard is on the track pad go immediately to step 8 and remove the plug for the pram battery.
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Where is power manager for FW 800 G4?

I can't seem to find the location of teh power management unit for the G4 FW 800 dual 1.42. Any reference material would be greatly appreciated.

The PMU moves around on various motherboards and within one class (there are at least 3 each variants of the 133 and 167 motherboards for Mirror Door Computers!)
The button is usually located in the center of a silvery box about 3/8" square and has a red button. They are usually close to the battery and usually say in microscopic print "pmu".
For the exact location go here
http://www.whoopis.com/computer_repair/#new
Download the manual for your mac, go to Views and the picture of your motherboard with the pmu location diagrammed.

IBook won't power on... power management issues?

Hey everyone,
_MY SYSTEM_
I've got a 12" iBook G4 (1.33 GHz) running 10.4.10 that's about a year and a half old. It's been a great computer for me, and I've used it on an almost daily basis since I first got it. Its experienced a few power-related quirks within the last month or so, however. I can't think of any event that would've caused them.
_THE SYMPTOMS_
I first started noticing that OS X sometimes displayed the low battery warning at odd times or not at all. I didn't think much of it... figured it could be my power adapter coming unplugged or something. Then I started noticing decreased battery life, but I chalked it up to the effect of fairly heavy use and lots of charge cycles. I continued to feel like my power adapter was getting progressively more finicky... it started requiring much closer contact with my iBook than it used to, but since it's a friction fit, I figured the contact was just getting looser.
_CURRENT STATUS_
When I turned the computer on this morning and plugged in the charger the status bar icon didn't seem to recognize it as attached to the adapter. The colored ring around the connection point would go green when connected, but never turn amber. So I used it today until it went to sleep on me. Tried plugging the adapter in, but the same issue existed... the ring would turn green but never amber and the iBook wouldn't actually charge.
TROUBLESHOOTING
I first tried another adapter with no luck. I was able to use the power button to shut my iBook down with the intent to reset the power management unit on startup. That key combo didn't even produce a startup, it just killed the adapter's indicator light for a brief moment. Unfortunately the battery seemed too depleted to start the computer back up. I tried zapping the pram, and that got me to the login screen before the computer recognized it was low on power and went back to sleep.
SUMMARY
As far as I can tell, the computer isn't recognizing either adapter when one is attached. The battery doesn't seem to be the issue. My iBook is completely unresponsive without the battery (only on AC power), and doesn't charge the battery when both are connected. Anyone have suggestions for me before I make the trek to the nearest Apple store?
Thanks,
Matt

If the power adapter seems looser when you plug it in, you might have a problem with your DC In Board. This is what the power adapter plugs into, and it can become damaged.
You can go to http://www.ifixit.com/ and look up the DC In Board for your iBook and see what it might take to fix it yourself. If you go to the Apple Store, have them take a look at it.
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After a one week logout and shutdown my macpro 1,1 laptop shows a black screen at startup attempts. The battery is fully charged and both resetting the power manager and zapping the PRAM have failed to permit startup. What else can I try?

After a one week logout and shutdown my macpro 1,1 laptop running OSx 10.6.8 shows a black screen at startup attempts. The battery is fully charged and both resetting the power manager and zapping the PRAM have failed to permit startup. What else can I try?

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hello, please try to [[Reset Firefox – easily fix most problems|reset firefox]] (this will keep your bookmarks and passwords) & also run a full scan of your system with different security tools like the [http://www.malwarebytes.org/products/malwarebytes_free free version of malwarebytes] and [http://www.bleepingcomputer.com/download/adwcleaner/ adwcleaner] to make sure that adware isn't present in other places of your system as well.
[[Troubleshoot Firefox issues caused by malware]]

Power Manager resets Display Brightness (T 410)

Has anyone experienced an issues with power manager where the following occurs? I have power manager set so on battery my display brightness is 10 and on AC the brightness is 15. If I restart Windows 7 and am on battery power, the AC setting resets to 10 and must be manually reset once I plug in the power cord. I am running windows 7 64 (not the Lenovo build) but have used system update and am currently up to date with no problems listed in device manager. Any ideas.
Thanks.

Hello mate,
Is the setting the same in both Power Manager and Windows Power Options ?
Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information on it.
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I have a Power Mac G5 DP1.8GHz/1.5GB/80GB which I bought non-working. It has not yet been disassembled or examined by a certified tech. This is it's issue (which replicates): the computer powers on. It makes a single warning tone, then the LED flashed at least 15 times (too fast to count). Then the posting chord is heard. Hard drive spins up. Then nothing (no video). Won’t boot from any disk. I have changed the RAM and tested the RAM banks with known-to-be-good RAM from another DP1.8GHz G5. The warning tone stopped once or twice after this switch, but then it didn’t chime. I changed the PRAM battery, but not with as new one. However, after installing the used one and then resetting the PMU, it displayed video briefly for the first time. While installed in the other 1.8GHz G5, the hard drive was formatted, given a clean install of OS X 10.4.11, and then moved into this computer where is never mounts. The computer is not accessible through TDM.
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Through my own trial and error troubleshooting, I have found the CPUs to be in good working order and the logic board passes the Apple Service Diagnostic every time. Despite the installation of numerous pairs of modules that worked in another DP1.8GHz, the computer has a RAM issue-it gives the "no good RAM" tone most of the time when it powers up (after a PMU reset it does not). Also the computer boots from disk or into Open Firmware but the disk utility can't see either hard drive so I may have a bad SATA controller.

Faulty Power Monitoring Unit?

I updated to 10.4.9 about a week and a half ago. I don't know if that has anything to do with my problem, but before that, I had no issues with my battery.
Recently, I was using my Macbook, running on the battery, and with about 3:30 remaining, it shut off into sleep mode.
I plugged it in and restarted it to find that my battery capacity went from 5200 mAh to about 550. That's TOTAL CAPACITY, not current charge.
So, I called AppleCare, and they told me to reset my PSU and PRAM. Surely enough, I was getting a correct reading for my capacity and charge.
I just charged my laptop before going to bed last night and I let my MacBook sleep while running on battery while I was at school. When I got home to use it, this is what the readings for my power were:
Current Battery Capacity - 6533 mAh
Original Battery Capacity - 5200 mAh
Approx. Time Remaining - 47 hours 49 minutes.
This was about 10 minutes after turning it back on, mind you.
I tried to reset my PSU and PRAM...twice...but to no avail.
Is my Power Monitoring Unit faulty, or am I not reseting it properly?
Help is appreciated.
NOTE: This Power monitoring problem only seems to occur when I let my MacBook sleep for long periods of time (about 10-12 hours). Could that have anything to do with it?
MacBook (White) Mac OS X (10.4.9) 1GB RAM 80 GB HD SuperDrive 2.0GHz Core 2 Duo

I am going into the Apple store tomorrow.
I have done 7 PMU Resets and 5 PRAM resets, all to no avail.
I swear, this battery is faulty. Please post new updates if you can. I may not be able to log on and reply because I'm having connection problems. Post any suggestions you can, other than a PMU or PRAM reset - those HAVE NOT AND WILL NOT WORK.

Power Management/Sleep Mode

Hi Guys,
I have searched the forum and not come up with what is going on with my new Mac Pro 2.66. When I got it, and set the energy saver to power down the monitor and drives at 15 minutes it worked just fine. Now all of a sudden it will not put the unit to sleep after 15 minutes. It will do what I have scheduled, that is to shut down at 11:00PM each night and start up again at 6:00AM in the morning, but during the day "will Not" sleep after 15 minutes. It will manually sleep if I choose that from the open apple menu.
I went through a series of diagnostics with Apple tech support, including removing all .plist files for energy saver and startup preferences, and also did a complete new install from my system CD's. The apple rep says it seems to be a power supply issue after he also had me reset the power management module by disconnecting all cables from the cpu, powering down and then waiting 2 minutes, restarting and then reconnecting all cables and peripheral devices.
Based on some of your vast experience, do you concur with apple tech support that a new power supply replacement may be in order?
Many thanks for your input...
Jim

Disk Warrior is essential. And no you aren't going to find a disk repair program dealing with corrupt files and directories that is shareware.
Onyx is freeware though.
http://www.macupdate.com/info.php/id/11582/onyx
I have gotten into trouble with TCC though I used it for years, never deep cleaning. For that I preferred Applejack (donation-ware). Onyx seems okay but also scares me with its "improved" and "corrected a bug in..." mentioned in updates. Seems excellent, and maybe it really is complicated.
I backup daily with multiple sets, use SuperDuper and follow up with Disk Warrior afterwards and as preventative maintenance.
MacFixit has some excellent tutorials on best practices for doing system updates and maintenance. I deep clean caches with Applejack.
TCC and Onyx have menu items to kill delete remove Spotlight. Or there is "Spotless" as well.

Windows 7 power management on macbook air

Has anyone had issues with power management in windows 7. I went into the power management and told windows to never go to slep or hibernate when plugged in or on battery. For some reason it keeps going to sleep. Then I turn it back on and it goes to sleep again. This is an intermitten isses, so it can happen at anytime.
Does anyone have any serious suggestions.
Thanks,
Lester

That does not jive with what happens at all - battery life is shorter, fans don't come on as expected, but there IS power management - sleep, 5% processor when idle, and all the other settings.
Reset the Air's SMC or power management control unit whatever and it does not sound normal.

My solution (or so I thought) to Power Manager/CPU throttling problems!!!

I have found a solution to all my Power Manager/CPU throttling problems!!! Though there is some good and bad news.
{EDIT: The problem has NOT been fixed, even after latest PowerManager (3.62) and BIOS (1.30) versions. Pretty much ignore anything I say below as the problem is still occurring. You can see my full post here: http://forum.lenovo.com/t5/W-Series-ThinkPad-Laptops/W520-Speedstep-not-working-properly-on-battery-...}
Good news: I have NONE of the throttling issues or inconsistent CPU frequency problems I was having before on AC or battery power. Everything, including TurboBoost on battery works! It is completely fixed! (I have no idea how this factors into Lenovo’s statements that TurboBoost is disabled on battery “by design”. There is at least one other post from someone else that also reported TurboBoost was working for them on battery)
Bad news: I don’t really know which one of the many things I tried actually worked. I am sorry I wasn’t more methodical about recording what I did and checking results, but this was my last ditch effort to get this fixed on my own without sending the system in for repair and frankly, I didn’t think it would work. Now that it has worked, I’m hoping my steps can help others.
For anyone interested, here’s what I did… and before anyone says something like “That has nothing to do with managing power/cpu, why would that help?!… etc., please keep in mind I’m just stating exactly what I did. I am aware some of the steps may not be relevant, but who knows… We all know how weird PC’s are sometimes, even the smallest, oddest thing may resolve a problem.So anyway, here goes.
**IMPORTANT** Not sure how many noticed, but there was a new version of Power Manager released a few weeks ago, 3.62. The PM driver seems to have stayed the same. That alone could very well be the sole fix, I’m not sure. You may just want to completely remove PM and PM driver and install the latest version before trying any of the steps below.
1)Made a complete system image via Windows built-in backup feature
2)Disable any 3rd party fan/CPU control utilities (Throttlestop, etc). Make sure they are also not going to run at startup or from a scheduled task
3)Remove Power Manager Driver, then remove Power Manager software
4)Reboot to Windows
5)Remove all traces of the Power Manager drivers/software directories (think it was something like C:\readyapps and C:\drivers.) **For some odd reason after I did this, my wireless stopped working but it resolved itself by the time I was done with these steps, strange
6)Reboot
7)Access BIOS and reset all settings to default
8)Boot into Windows, downgrade to BIOS 1.25 [UEFI: 1.25 - 8BET44WW / ECP: 1.14 8AHT32WW ] via the Windows flash utility. I wanted to downgrade all the way back to 1.06, but the software would throw up some error for any version prior to 1.25 and wouldn’t proceed
9)Reboot to Windows; make sure system booted w/ out issues
10)Reboot again, access BIOS, reset to defaults again
11)Shut down system
12)Disconnect AC power. Remove main battery. Access and disconnect system backup (a.k.a CMOS) battery under keyboard. Discharge residual power in the system (there are various ways to do this, but you could just leave the battery disconnected for a few minutes). Visually inspect the system for anything funky…my system had a slightly but noticeably loose CPU/GPU heat sink/fan assembly power connector.
13)Reconnect backup battery.
14)Reconnect AC power but leave main battery disconnected.
15)Power on. Should get a message indicating “checksum error, system time reset” or something like that.
16)Reboot to Windows. Verified still okay.
17)Downloaded latest BIOS version, 1.26. This time I burned the bootable BIOS flash CD instead of running it through Windows.
18)Restart and boot from disc, flash BIOS to 1.26. Once complete, restart. Verify BIOS set to defaults.
19)Boot back into Windows.
20)Install latest Power Manager driver (1.62 ), reboot if/as prompted. Install Power Manager (3.62), reboot as prompted.
21)Boot into Windows, verified Power Manager was active and working. Verified TurboBoost was working. Restarted system a few times and played around with Power Manager for a bit to see if the different power plans worked and retained the settings, all the while monitoring the Intel TurboBoost utility and PM’s own “power gauges”. Let system Sleep, changed power sources, resumed, etc. Everything was working great.
22)Shutdown, reconnect main battery. Booted into Windows. Again, fiddled with Power Manager for a bit, switching between power plans and AC/battery power. Still worked great.
23)Success!
That’s it. Again, this is not a guaranteed fix guide. These are just simply the steps that I took on my system that resolved the problems many of us are having. Hopefully it will work for others.
T520 4239-CTO | i5 2410M
W520 4270-CTO | 2720QM | 16GB RAM | Quadro 1000M | BIOS 1.30 | PwrMgr 3.62

All I basically did was download and install...
(Chipset driver) http://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles/oss924ww.exe
(PM driver) http://download.lenovo.com/ibmdl/pub/pc/pccbbs/mobiles/83ku14ww.exe
Now, I did chipset first (didnt ask to reboot) then installed the PM driver (did ask to reboot)
I rebooted.... then I went into bios (1.26) and set everything to default... then restarted saving changes...
Since I prefer not using optimus I changed the display settings in bios right after saving the default settings...
Not sure whether or not you really had to go into bios... but everything seems to be working...
My settings in PM is set to Maximum Power in the Advanced tab, 3rd party monitoring tools is TPFanControl and HWInfo64....
W520 (4270 CTO) | i7-2820QM | 16GB RAM 1333 MHz | Runcore MSATA SSD | 2x Kingston SATA2 SSD | Quadro 2000M | FHD | Windows 7

Reset power management unit (PMU) 12" PB Aliminium case

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