Why doesn't logcat show anything in my Android?
Dial
*#*#2846579#*#*
and you will see a hidden menu. Go to the Project Menu > Background Setting > Log setting and define the log availability (log switch) and level (log level setting).
Please note this may apply to Huawei phones only as is stated for an Ideos X3 (here) and is tested at a Honor U8860.