This message is posted when you unlock the screen orientation (switch left):
[ 09-26 22:16:01.830 141:0xaa V/Sensors ]
enabled_sensors: 16384 dmp_started: 0
...and when you lock it (switch right):
[ 09-26 22:16:05.020 141:0xaa V/Sensors ]
enabled_sensors: 0 dmp_started: 1
If you see those messages when expected, your switch is functioning normally.
If you see the following messages in rapid sequence when the switch is set to unlocked, then you have encountered the Iconia ICS motion sensor initialization failure. Error messages print in aLogcat in red text.
[ 05-04 06:51:48.520 141:0x99 E/Sensors ] MLUpdateData error (code 26)
[ 05-04 06:51:48.570 141:0x99 E/Sensors ] MLUpdateData error (code 26)
[ 05-04 06:51:48.620 141:0x99 E/Sensors ] MLUpdateData error (code 26)
If the switch function is normal, and the code 26 errors are never being posted, then you have some other problem. Advanced Tools by SCDevs includes a good collection of sensor test tools. You may also want to check for apps that may be interfering with normal sensor operation. Apps can control and affect sensor behavior. If you are not sure which app is causing problems, you can try a Factory data reset to clear everything.