The following article gives information about touch screens not working after power management settings are changed.
You may encounter a situation where the touch input of the touchscreen display will not work after the power management disables the touchscreen.
EXAMPLE: If you set the screen to DIM after 2 minutes and TURN-OFF after 3 minutes. Moving the mouse, hitting any key turns the display back on, but the touch input no longer works.
Cause information is not available.
The solution is to adjust the power setting in device manager under Human interface Devices (HID) devices (Figure 1).
Figure 1
To resolve this issue, complete the following steps:
Open Device Manager.
Windows 7:
Click the arrow next to Human interface Devices. You should see 2 items that are listed as a USB device.
The touch screen should retain touch functionality after it is turned off. You can use either the mouse, keyboard, or touch screen to turn the LCD back on (Figure 2).
Figure 2
If you have further questions about this solution, please contact Dell Technical Support.
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