Even I faced the same problem. I took the phone to LG service centre in Mumbai and as expected it had power button malfunctioning. There is a tiny button on the motherboard which needs to be replaced. It involves desoldering and soldering job so it is slightly specialized one. They charged me Rs.381/= and was told that bill will be coming to my email ID, and I am expecting the same anytime. Let me share one more experience for the benefit of all. If you take to some LG service centers, they may tell you that motherboard is needed to be replaced and will involve an expense of a tune of Rs. 10000/=. My sincere advice is that in that case try some other LG service center and insist on replacing the power button. This has happened to me that is why I thought I should share with all. Good Luck and Enjoy!!