T400 comes out of standby randomly

Hi everyone,

I've had my T400 that I bought for school since last September, and it's always had an issue where it sometimes comes out of standby / sleep mode for no reason. This can be dangerous for the machine because it has happened when I had the notebook on sleep mode in my backpack and it was on for a good couple hours in there, just heating up everything. Happens with things plugged into USB, whether I'm on A/C or battery, whether I just close the lid or select sleep from the shut down menu.

I have a suspicion that it has something to do with the screen hinge being messed up, such as the notebook detecting that it was opened when it actually wasn't. Anyone think it could be something I can fix on my own? Or am I going to have to get it fixed by Lenovo before my warranty runs out in September? I want to have this machine for a good five years. SSD drive and 4GB of memory and this thing will be good for a long time, for me at least

Thank you

 

I'm almost 100% sure you don't have to worry about a screen/hinge problem. Thinkpads coming out of sleep is a very common problem that occurs due to the stock power settings which are set in the Windows and Lenovo Power managers. Also network adapter settings which are set to "wake on lan" can also be responsible.

What you should check is basically three or four things and you're sure to find the culprit:

1. Right click on the desktop and click Personalize -> Screen Saver -> Change power settings -> Change when the computer sleeps -> Advanced Power Settings -> change these to how you prefer them.

2. Open the Lenovo Power Manager -> Switch to Advanced -> Global Power Settings -> Disable 'Always on USB'

3. Start menu -> Right click Network -> Properties -> Manage Network Connections -> Right click your Wifi adapter -> Properties -> Configure -> Power Management -> uncheck 'Allow this device to wake the computer' (Do this for all of your network adapters.)

Also, unplug your USB devices before entering standby.


Hope that helps. If you still have the problem then let us know.

 

Thank you - 1. and 3. were already how I wanted them as you suggested, but I did your suggestion in 2. I will come back here and let you know if the problem persists, it could be a bit because it isn't easily reproduced.

Thanks again!

 

Sounds good, just be sure to disconnect your usb devices, especially the mouse since even with 'USB always on' disabled, a mouse still has the ability to wake the computer up from sleep with just one click.

 

There is a registry patch for this if I recall correctly. Doubtful it wouldn't be already installed, but then again...
check the drivers page, there are a bunch of registry patches there (yeah, I know, too many, but check the txt files and see what they do, one of them should be about waking the computer)