The lid switch of the notebook Lenovo Thinkpad X230i had worked just fine: closing the lid led to a suspend as expected. After an update of the system on the 18th of September the lid switch seems to be not recognized any more.

If I manually click on "Suspend", it works fine, so suspending is not the core of the problem.

I tried to read the "Lid" state, by entering while [ 1 ]; do cat /proc/acpi/button/lid/LID/state; sleep 1; done in the terminal and also by trying watch -n 4 'upower -d | grep lid-', but the reported lid state is always "OPEN". My strong assumption is that the lid switch did not physically break at the same time when I did the update. Also, the notebook is just three weeks old.

Is there a way that I can fix the correct reading of the lid state in Ubuntu? Thanks a lot for your help!