iPhone 4 wont recognize my sim
Hello, I changed my screen and after putting my iPhone 4 back together it wont recognize my sim nor any other sim. I can't seem to find the problem. Please help!!!
第四代iPhone。维修过程直观易懂，但前置玻璃和LCD面板无法分开，只能作为同一零件更换。GSM版本， 8, 16, or 32 GB 容量 / 型号 A1332 / 黑色或白色
You may have damaged the sim junctor that reads the card. Have you cut your sim card to fit the micro sim? Also, try using canned air to blow any dust out of the sim card slot. Also, make sure the logic board is sitting in the phone properly. It sometimes likes to fit in wrong, but look right.
They can be some simple fixes for your iPhone not picking up the sim.
1st is your time and the date configured properly?
If not go to;
-Date and Time
-Make sure this is set properly. This normally fixes the problem.
If it doesn't you may have other more serious issues. Like a damaged SIM Card reader.
Which can most likely be damaged while putting the phone back together, if so you will have to open it up and soldered a pin back on. This can happen when you reinsert the tray and the circuit board is not seated down properly (occurring when you possibly miss a screw inside etc....) It damages the pins and damaging just one is enough.
Also as I explained it could be more serious, make sure you didn't lose the little blue inductor to the bottom left of the aerial cable.
-I suggest that if your having this issue that you take the back off with the phone still on and try to bridge the gap left where the inductor used to be by lifting up the L shaped ribbon on the bottom left hand corner. (do your best to remain ESD safe) Take a flat bladed screw driver to bridge the gap between the 2 solder points where the inductor was, this should bring back signal immediately, proving that the blue inductor was the problem. Use some solder to bridge the gap and this should restore the connection and get it to work again.
(remove the logic board to avoid damage to the dock/speaker assembly)
Over time just like most electronics solder heats up and cools down, 100s of times while your phone is in use this blue inductors solder becomes weak over time at all, and can fall off if bumped or moved.
Hope this helps!