I've seen this and while I know what it was on that phone I can't write it will be the answer. So I'll share it just in case.
In this phone it was some app. We had to remove apps until we found which app was doing this.
Bob
My Galaxy Wonder I8150 screen keeps brighting up every now and then while being on lock screen. This seems to happen in an organized manner like after 4 mins from being locked strats brighting up then every 10 secs and stops for a while and the cycle starts again...
I tried many things: used task killers and adjusted them to kill tasks automatically every 5 mins to kill those tasks running in the background, removed several Apps which I suspected they were the cause, changed all App settings to avoid having them on at Android start up...but all in vain !!
Just to add on days it never happens as long as I have the phone under my eyes, on other days it keep on that manner..it has been like this since yesterday and it really bothers me
So does any one faced such a problem, and if so does any one has a solution for this & knows how to fix it ??
Thnx in advance..

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