Help no signal

[Peligro911]

Need some help here my friend has a iPhone 3G ( that I currently have to try to fix ) it is 4.2.1 bb 6.15.00 unlocked to tmobile .. Everything was working great I even got mms to work then his sister dropped it .. Nothing looks broke not shattered etc. Except now I get a no service where my signal should be .. I tried the hard reset the airplane on and off and reset network settings .. It will lock on to tmobile for a couple min or so them drop out to searching and then no service this also happens with a AT&T sim . Sometimes I can get it back sometimes not ... I opened up the phone nothing looks broke or damaged I'm kinda at a loss besides to tell him its now a iPod
And ideas ?

 

[Peligro911]

Correction to my previous post it's running 4.1 but still don't have a clue

 

[uchijo6]

While nothing make initially look damaged, I would completely reseat all wires/cables just to eliminate the possibility that it's just a loose connection! I've had times in computer repair where the entire problem was due to a half connected cable.

If that has been done, then it might be something on the logic board internally snapped so getting minimal connection.

 

[Peligro911]

I updated to 4.2.1 JB and re unlocked and it fixed the prob .. Maybe had brain damage and I had to reload lol idk