If you own an Huawei tablet and your screen timeout is grayed out, then don’t worry. This problem can be solved with a few simple steps.
Turn Off Power Saving Mode
First, you need to turn off the power saving mode.
Go to Settings -> Battery -> Power saving mode -> OFF
Then follow the following steps to change screen sleep time on your device:
Step 1: Go to Settings -> Display.
Step 2: Tap on Screen Timeout.
Step 3: Select 30 seconds or any interval that suites your need.
Optional Step: Turn off the tablet by pressing power button for 10 seconds until the screen turns off. After a while, turn it on again. Once it’s up and running, go into settings and check your screen timeout setting again, you should now be able to set a timeout time.
I hope this helps anyone who has been having this problem on their Huawei tablet.