Stuck on apple logo screen

Hello guys!i have an iphone 4 where after a through on the wall the IC Skyworks SKY77541 GSM/GRPS Front End Module its been detached but it was working fine but without signal.i try to tached it again with a heat gun and i success but after this the only thing that i see when its turning on is the Apple logo.i cant put it on DFU mode i cant repair the start up section with a third party program where i found i try to change the battery and the dock connector i still nothing.i also try detached again the IC and nothing at all.any other ideas guys?sorry about my English.Thank you.