Very Poor GSM Signal after Screen Replacement.
I have an iPhone 4S that a customer of mine left with me, didn't ask for anything and as far as he knew only the screen was broken.
Sure enough the screen was broken, so I replaced it, and also the dock connector as it was no longer charging anymore.
There was no water damage (indicators are white, not red and no corrosion seen.
After reassembling with both parts replaced and preparing for a resale, I tested with a sim card and it stayed on searching for a while, then no service.
I already know the searching...3G bug so I Power cycled and connected to wifi to obtain the correct date and time.
After a while it will search and then go no service. I checked the IMEI, still there. I went into the carrier option (it becomes available so I know the SIM is being read) turned off automatic, and all that came up was rogers wireless (I am using telus and on my other test phones I have 4 bars of LTE service in my location and 3 Bars of 3G service on another 4S)
Convinced it was a signal issue, I attempted replacing the housing, with another 4S housing currently in use with no issues, still the same issue.
I read about the blue resistor, and as far as I can see mine is in tact:
Please help if you can, I would like to get this phone working!
Also, perhaps related, the wifi clip was in the antenna here is a picture, hard to explain.
When held down under the black grounding clip, the phone has wifi signal up to par with a phone not in this condition.