I dropped in toilet my nexus 4.then soon I took it to service center they didn't help but clean just motherboards and other parts then told me charge it if ur lucky it will work.but it didn't for sometime I got charging icon whenever I pulled in charging pin then took phone to a local hardware guy he fixed power ic then booted up now it works just fine but the screen brightness is very low I'm mean very very low.other than that no problem.he said that's all he can do.what should I do replace my battery? Will that help get rid of low brightness..pls help!!!