Answer to: iPhone 5 microphone not working during callsHi Sumit, i assumed you only use 1 piece of spare part. try other pieces and check if it working again. sometimes spare parts do malfunction/defected.
Answer to: My touch screen doesn't workReplace the screen.do not try it yourself if you are beginner.iphone 4 screen replacement need some set of skill to replace.
Answer to: wifi is greyed not working after restoreHello, This wifi grey for iPad 95% due to malfunction of wifi port/board "''something that connect the wifi cable network"it is small board in the main PCB. change this port/board and your problem solve like forever.http://postimg.org/image/tkrzc35nr/