kusam no dessicant in the world is going to work unless you totally disassemble your phone.Disassemble your phone using [https://www.youtube.com/watch?v=sd5Q7A67WqQ|this video] and clean everything after you remove all the EMI shields from your circuit board. If you do not remove those you are not cleaning most of the board.
Clean everything with +90% (no less than 90%) isopropyl alcohol. Follow [guide|5825|this guide], and even so it was written for an Apple iPhone 3G all the points are still pertinent to your phone. Pay particular attention to the SMD components, check for charred missing or broken missing. You can then dry the board in an oven or equivalent at 220deg F (not higher;-) for a few hours. Best way to clean it would of course be through an ultrasonic cleaner. Consider professional help with that When it is properly cleaned, ''' replace the battery'''. All these steps are to avoid delayed failure caused by corrosion. Once all this is done, reassemble your phone and reevaluate.
As always, if not sure what you are looking at or if you are unsure if your board shows corrosion or missing, damaged part, post some pictures with our question. For that use this guide [guide|21499]