Computer keeps going into sleep mode

There may be a number of things to try to establish the fault.

1. Go to the utilities, console and open this up press the logs button and take a look at the system logs, it should give you some idea of whats happening i.e power management recieved an emergency overtemp signal going to sleep...
or something like that.

2. run the Apple hardware diagnostics to see if it finds any faults with any of the hardware. This should be on a cd that came with the machine.

3. if its a thermal problem then do a search on google for temperature monitor OS X. Set the preferences to update every second. Get it running and take a look at the history if one of the sensors is acting wildly then it can be a bad sensor. (trackpad sensors seem to be a favorite to go wild).

4. Also do a seach for smartutility and have a look at what this says. If it says your hard drive is failing then get it replaced.

You may wish to format the drive and reinstall everything but personally once a drive begins to have problems I wouldn't hesitate to change it.

I had similar issues with a 1.67mhz powerbook, every diagnostic and test I ran found nothing yet it would sleep sometimes every few minutes. Even after reinstalling the sytem, resetting the pmu etc. Every utility I ran told me all the hardware and hard drive was fine, except smart utility. I cloned my system onto a replacement drive replaced the drive and its been fine ever since.

If it's a temp sensor then if you search around there are ways to disable them by removing certain files from your system library. You can search in google for this info. Or you can take it apart and physically remove them, but I woulnd't recommend it. The trackpad sensor is a small chip mounted close to where the on off button wires connect to the trackpad ribbon cable. I believe it's made bt texas instruments and bears the number 7751 (if I remember rightly, you will need a magnifiying glass to see this). It can be desoldered aparently.

Other wise you may need to take it to a store to be fixed, typically it would be a top case replacement. But other people may have other issues so that may require a logic board or hard drive replacement.

I don't think this issue is down to any one cause, just results in a similar effect.

Good luck

Just to add a me toofor the PB12"G4, after a new battery/drive etc apple said the board was broken and would need replacement.
Logical thought indicates do not buy mac laptops as they do not work after a while and apple will charge you for lots of components as a reductive test as opposed to a clear cut solution. Three cheap PC laptops might be better.
I suppose they read these forums occasionally.

I'll "annotate" 4pack's post with my own experiences and what kind of evidence I collected before going to the genius bar.

4pack wrote:
There may be a number of things to try to establish the fault.

1. Go to the utilities, console and open this up press the logs button and take a look at the system logs, it should give you some idea of whats happening i.e power management recieved an emergency overtemp signal going to sleep...
or something like that.

That is correct - that will occur every time the machine goes to sleep

2. run the Apple hardware diagnostics to see if it finds any faults with any of the hardware. This should be on a cd that came with the machine.

A little tip here - run the extended test when the trackpad temperature sensor is playing up - the test should then fail at the Logic Board section with the error code "*2STH/1/2: TRACK PAD*" - show this to the Apple Store Genius and that should help them out a lot!

3. if its a thermal problem then do a search on google for temperature monitor OS X. Set the preferences to update every second. Get it running and take a look at the history if one of the sensors is acting wildly then it can be a bad sensor. (trackpad sensors seem to be a favorite to go wild).

Before taking your computer in to Apple, take as many screengrabs as possible of the trackpad sensor going wild - and make sure they're in a clearly labelled folder and the genius knows about it - they should record this in the case notes.

4. Also do a seach for smartutility and have a look at what this says. If it says your hard drive is failing then get it replaced.

You may wish to format the drive and reinstall everything but personally once a drive begins to have problems I wouldn't hesitate to change it.

I never checked my HD - disk utility never seemed to turn up any problems. Mind you, doing a clean install of OSX (and zeroing the HD) did nothing to help solve the trackpad issue.

I had similar issues with a 1.67mhz powerbook, every diagnostic and test I ran found nothing yet it would sleep sometimes every few minutes. Even after reinstalling the sytem, resetting the pmu etc. Every utility I ran told me all the hardware and hard drive was fine, except smart utility. I cloned my system onto a replacement drive replaced the drive and its been fine ever since.

If it's a temp sensor then if you search around there are ways to disable them by removing certain files from your system library. You can search in google for this info. Or you can take it apart and physically remove them, but I woulnd't recommend it. The trackpad sensor is a small chip mounted close to where the on off button wires connect to the trackpad ribbon cable. I believe it's made bt *texas instruments and bears the number 7751* (if I remember rightly, you will need a magnifiying glass to see this). It can be desoldered aparently.

Interesting... my new trackpad is made by Apple Computer - they must have restarted the production line. Can anybody confirm what their system proflier says about the trackpad manufacturer?

Other wise you may need to take it to a store to be fixed, typically it would be a top case replacement. But other people may have other issues so that may require a logic board or hard drive replacement.

And when you go into the Apple Store, gather as much evidence together (like system.log lines, hardware test failures and temperature spikes) - this will help the geniuses solve the problem.

I don't think this issue is down to any one cause, just results in a similar effect.

At the moment, replacing the top unit (£195.05 including labour) has solved the problem, but I only got my PB back last night.

The trackpad sensor isn't actually part of the trackpad assembly, it is stuck to the orange ribbon cable that connects the trackpad to the logic board. The actual location of this on my 1.67 Ghz 17" G4 is just below the spacebar to the right (if you were looking at the powerbook in normal use). Perhaps in the longterm it's all the bashing of the spacebar that eventually upsets it.

The trackpad assembly is listed as an apple computer part in the more info pane. And the ribbon cable is glued to the topcase, which is why its a top case replacement rather than just a part replacement, although this may change if Apple gets a lot of these in for repair.

I ran the Apple hardware diagnostics, both standard and extended tests several times with no fault being found.

I disabled various thermal extensions to stop the sleep issue without sucess, the only sure way was to remove the Apple PMU extension, but then in doing so the machine wouldn't sleep correctly wouldn,t wake up, and wouldn't always shut down correctly. So not especially usefull.

I reinstalled the operating system 10.4 (twice) it seemed to run better on a fresh install rather than a more recent update, but I think this was just a random coincidence.

On mine disk utility, disk warrior 4 and tech tool pro 4.5.3 reported no hard drive problems and all reported the smart status as ok. The only incliniation that I got on just 2 occasions when I did a hardware test with diskwarrior it told me the hard drive was running at higher than normal temeperature of 25ºC, which isn't high, was in tolerence and was actually the ambient air temeperature.

Looking at the drive with smart utility I was able to get a full smart report that showed the drive had a number of bad blocks along with other faults and said it was failing.

When I was running temperature monitor it never once found the trackpad sensor, all the other sensors seemed fine apart from the hard drive sensor which would randomly stop responding, even though the drive was set not to sleep. There were no peaks or troughs in the data it captured. I can only assume my trackpad temperature sensor has already long since died. Although temperature monitor can't find my new hard drive temp sensor, istat pro and other utilites can. So I think temp monitor perhaps is not perfect.

I can only assume that the hard drive or drive controller was starting to fail, as since its replacement I have had no issues. I did not install a fresh OS onto the new drive just used carbon copy cloner and an off the shelf sweex USB Firewire drive caddy to transfer the data to a new Toshiba drive.

On an interesing note, I had been fiddling with the PMU extension owner privilidges, with no result however only when I installed the new drive did the system detect this and complained. I reset the original prefs.

If I get any further problems then I'll remove the trackpad sensor as It's physically there, perhaps it just pops up evey now and again with a stupendous reading causing the OS to throw the toys out the pram. But for now so far so good.

This has probably been one of the hardest faults I have ever had to diagnose on any system and I'm involved in field support and repair on PC's Macs and servers of all flavours, so I get quite a lot of weird and wonderful problems. Including a very similar issue on a brand new Sony Vaio laptop running Vista, I spent ages going over that one too, I eventually tracked it down to the user wearing a magnetic rhumatisim braclet that activated the magnetic lid catches making the thing think it had been shut!!

I spent probably over a week solid running every type of test I could get my hands on without much hint of any problems, and spoke to both other independent Apple tech guys as well as Applecare support.

This is a tough one so don't be too hard on the tech guys if they can't immediately find a fault. My only hint that it wasn't a more serious hardware fault such as logic board was that when running the dignostics or installing the system the machine would run fine unhindered for hours, only when running on it's full installed operating system would it fail.

But I wouldn't suggest this is the answer to everyones problems, just that there may be more than a single issue at work here, and it's a careful process of elimination to find out sometimes what isn't causing the problem.

Before taking the machine to the shop its kind of necessary to do some of these steps, like reinstall the system (which isn't very painful) run the apple supplied diagnostics and resetting the PMU even if it doesn't work, it eliminates these from the repair process. if you take it in they will only ask if you have done this anyway....

Message was edited by: 4pack

well as if to mock me after a week of faultless operation my powerbook sleep issues returned!!

So I have now also removed the topcase and desoldered the offending trackpad sensor chip. It's all back and working as though nothing is missing and fingers crossed the sleep issue should now be at an end.

I'll post back if it returns.....

The problem just started appearing now in my mac after 2 years of normal use. Yes, keep going the "ME TOO" list!!
And it started just after I decided to leave the computer on sleep mode all the time, everyday and plugged to the ac.
This was the advice the guys at the apple store gave me.

Before I used to turn off my computer and unplug it from the ac before going to bed so it would cool down at night.
Then I would leave it in sleep during the day and I never had any kind of problem.
So I think that leaving the computer plugged and without turning it off every at least two days triggered my computer to be a narcoleptic.

I am just gonna try to use either the battery, or the ac(without batt)if I am at home, and turn it off every night or two. Also I am
not going to use too many applications at the same time. But that was not the idea when I got Mac powerbook!
The most sad thing is that I used to be a very happy user but now after barely two years of spending my $2400 for this "high end" computer
I cant use it. I am writing this from my girlfriends 8 year old dell pc that never ever stop working no matter how old the
programs are. Its Reliable.
SO C'MON MAC! dont let us down. I still think mac is awesome but to not be able to use my computer and have to put down more that $300 in order
to keep using it, is ridiculous. And I was telling her to get a Mac but now I think the next computer should be a good reliable pc.
Still as a photographer I like mac features. I hope the apple guys understaund that this IS a hardware deffect and I should get it fixed by them
otherwhise I will have to pay for the top case but only because I really need the compu and dont have money to get another one.
But I am not gonna be happy any more with apple. And the trust is gonna be gone.
We will see, I will post again telling what happens...

Yep, me too. Mine started this crap about a month ago. It goes to sleep and will not wake up. The only way to get it going is to either let the battery go flat or pull out the battery for 30 mins. I am lucky as I am in my 3rd year of Apple Care - thank god. I just have to organise my Powerbook to be sent to a service centre. I shudder to think how many PB's this is happening to!!