iTunes giving error 28
i have a iphone4 black 32 gb . it fully cracked from screen side. but i can receive calls but cannot see anything on the screen. it also recognize on the iTunes. i restored it on a 5.0.1 and activate it. i took out the logic board and put into the another phone . now it shows when ever i out the battery inside it goes to DFU . after battery fully drained putting on the wall charger it shows charging symbol and after few minutes it shows only apple logo on the screen and remained there. if we remove the charger from the phone it goes to DFU at the same time. i tried to restore with 5.0.1 but after preparing iPhone for retire it gives the error 28.
1. i changed the battery with other phone... but same.
2. change the dock connecter with other phone.. same .
3. put the logic board into the other working phone still same as before.
4. i took out the logic board for 4-5 days to fully discharged but same
5. i removed the shield from the board. i saw the one ic is automatically removed from the board . now what to to?