Windows 7 Laptop Randomly Sleeping

I'm running Windows 7 64-bit on a Lenovo laptop, and I have a problem wherein after I've put it to 'sleep' once, it will seemingly without any reason or warning go back to sleep every 10 to 15 minutes after that.

Each time it wakes back up just fine, and you can happily continue on. However, 10 or 15 minutes later, it just drops out into sleep mode.

I don't see any errors in the system logs. I don't think it's related to heat ( since it's not rebooting ).

When I check the system event log, I can see where the machine goes to sleep, but it simply says "reason: application API", and doesn't indicate which app ( brilliant ). I don't see any errors from hardware or anything relating to sleep in the application log that would point to what is going on either.

How can I find out which app is triggering this?

EDIT: I confirmed that temperature wasn't the issue. I think it's important to keep in mind that this condition only happens after the first sleep. If I reboot, the problem goes away until I put it to sleep, after which it sleeps on it's own every few minutes. Is there no way to capture which app is calling the sleep routine?

Josh Arenberg

Posted 2011-09-26T11:07:50.373

Reputation: 151

which power management setting are you on now? – Journeyman Geek – 2011-09-26T11:16:20.043

I've tried several power management plans. Currently on a setting that should never go to sleep. – Josh Arenberg – 2011-09-26T12:18:00.860

@JoshArenberg : I wouldn't necessarily rule out the possibility of temperature being the cause. There are several posts on forums regarding ThinkPads randomly going to sleep where overheating was identified as a probable cause, e.g. http://forums.lenovo.com/t5/T61-and-prior-T-series-ThinkPad/T61P-Randomly-Going-to-sleep/td-p/79038. I would use something like SpeedFan or HWMonitor to check your temperatures. If overheating is indeed the issue then a program called TPFanControl (http://www.staff.uni-marburg.de/~schmitzr/donate.html) may allow you to fix the issue.

– James P – 2011-09-26T14:40:57.930

If temperature is not the issue then I would recommend disabling non-critical third-party services a few at a time to see if it makes a difference. You could also try updating drivers, particularly the chipset drivers. As a last resort a BIOS update might worth a go. – James P – 2011-09-26T14:59:38.720

Answers

I had exactly the same problem. Lenovo, Windows 7. After the first suspend, machine goes to sleep automatically ("reason: application API" ;) ).

In my case the Lenovo PM Service was the problem.

After disabling this service (using msconfig) the problem disappeared.

The same link (http://answers.microsoft.com/en-us/ie/forum/ie8-windows_other/windows-goes-into-sleep-mode-on-its-own-while/9017bdac-9fef-4f7c-9e56-47976d30b7e3), as in previous answer, was helpful.

Addendum: I have installed the latest software from Lenovo: Lenovo Power Management Driver for Windows 7 (v.1.65.05.21), Power Manager for Windows 7 (v.6.45). I have installed the latest BIOS (v.3.25) in my T500. Unfortunately, it does not help. The only solution is - Lenovo PM Service disabled.