How does X61T determine that the lid is in closed position?

[davekung]

This problem started to creep up over the past few weeks.
I have my OS set to Hibernate when the lid is closed.
4 out 5 times, when I closed the lid, OS did not go into hibernation.
So for now, after I close the lid, I have to press along the edge of the screen lid until I see the blinking sleep LED, signalling the OS is entering hibernation mode.


Wanted to know if closed lid is determined by a simple switch, light sensor or something else.

looking for your experience and input.

Thanks,

David

[crazyfrog]

Probably something inside the hinge. Alternatively, you may press Fn+F12 to turn ThinkPad into hibernation if closing the lid does not work any longer.

[richk]

There is certainly nothing in the hinge. I don't have one of that model in front of me, but the other ones of that age (t60, r61, r61, etc) have a magnetic switch in the inverter and there is a tiny magnet under the keyboard bezel.