04-23-2019 08:20 AM
We've got one 20A7 X1 Carbon laptop that has developed a strange problem that wasn't solved by a complete format, reinstall of Windows 10, install of all Windows Updates & installing all updates & drivers from Lenovo Vantage.
The problem is reproducable every time for this laptop only by...
1. Plug laptop in to OneLink Pro Dock which has two monitors attached
2. Close Lid of laptop (the power settings are set to 'close lid whilst plugged in' = do nothing)
3. Desktop Windows Manager (dwm.exe) goes to unusually high CPU (about 10% on this i7)
4. Mouse pointer disappears and reappears on the screen, making it unusable.
5. The Display Settings screen still shows the laptop screen, whereas on working machines, the laptop screen disappears from there whilst the lid is closed.
Opening the lid again returns everything to normal. We've tried other docks. We've tried other monitors & mice. It looks to us that something in dwm.exe is trying to do something with the laptop display but not completing.
We're wondering whether there is a problem with a lid-close sensor? Or something else? Device Manager is not reporting any malfunctioning devices.
One change that we noticed was that prior to the Format/Windows-reinstall was that when the lid was closed the laptop screen was still lit and showing a display, whereas after the reinstall, the laptop screen turns off when the lid is closed but still shows in Display Settings.
Does any of this point to a fault that someone understands?
Solved! Go to Solution.
04-24-2019 07:38 AM
Have discovered that if we hold up a magnet in the centre top of the lid, the lid close function works properly. No dwm.exe CPU issue or mouse issue. So it seems the problem is with the magnet.