Used phone that has been refurbished Help

Hello, I have a buddy who wanted me to try and take a used samsung impression and fix it.  The body of the phone was trashe, screen was scratched terribly, and the touchscreen didn't work at all.  I bought a 25 dollar oem housing and digitizer kit off of ebay.  I went threw the pain stacking process of replacing everything.  Once i powered it back on it booted right up and the touch worked, as a matter of fact it appeared that everything worked like a new.  However, once we place the sim card in and booted it up the phone would never show any signal bars and would never go to att.  I did a factory reset using the master and still nothing.  Is it safe to say this phone is done for.  I would love any ideas and or help with diagnosing this poor poor impression.  Thanks in advance for any help.

Yeah i've tried both mine and his sim card.  You said do i still get data?  I know that before if there wasn't a sim card in the phone it would still register 3-4 bars but know it doesn't show anything.