iPhone constantly searching for carrier (no service)

"If the SIM card is properly in it's place, then you should read the following:

Since the iPhone is getting a weak signal and loses the signal within a few seconds, I would say that there is a problem with the antenna area (connectors/antenna).

If full reception is available, but the iPhone loses the signal within 5 to 10 seconds, it would normally be a defective power amplifier or a broken antenna switch (most likely the switch would die first when a phone is dropped).

The ""no service"" message in those two cases is normal: the phone receives the signal but the BTS (Base Transceiver Station) does not receive a signal from the phone (something like a handshake). So it does not ""lock"" the ""cell"" to the phone and goes on; it simply doesn't see or hear the phone, and that is the short explanation for why you get the ""no service"" message.

But what now ?

If there is nothing to see from the dropping and the phone is still under warranty, go to Apple!

If not, open the phone and check the connector between the dock connector and the logic board: it may be slightly dislocated.

You wrote that you checked the connections. This could mean that the antenna is defective, but check the connections again. Checking is better than buying a new part ;-)

Here is the guide for the dock connector."

"I had exactly the same problem with iphone 4.

This is what I did:

1. sync and backup phone on itunes

2. settings - general - reset - erase all content and settings

3. set up phone again using itunes backup

It did the trick!

Goodluck"

"iPhone no service error 100% fix in 5 minutes

I had this issue for about 1 month & i went through everything- Googling,yahoo search & apple discussion.

At last I have fixed my iPhone4 in 5 min.

First of all u need to know if it a software or hardware issue-

1. Toggle airplane mode for 4 seconds & wait for network.

2. Reboot iPhone.

3. Network reset.

4. Manually choose network.

5. Hardware repair method-

(Switch off your iPhone & take out the sim tray before continuing)

Take out the 2 screws from the bottom near the speaker mesh. Slide up the back panel & take it off.

Now take off the battery by taking off the little screw on the battery terminal.

You will find a very thin black wire near the battery terminal with a small plate on its end.

Near the terminal stand u will find a place to fit the plate. First clean the plate with a cotton cloth gently.

Connect plate on its place it & press it a little till u hear the little sound- tick.

(*Remember not to press so hard*)

Connect the battery & put the screw back. Get the back panel again & put the bottom screws.

Yippee..!!! U have fixed the annoying- NO SERVICE error on iPhone 4."

Try checking if the sim card is in right, it might be not properly in it's place, use this guide to guide you.

"There is a TEENY TINY inductor on the motherboard which is apparently very easy to knock loose of the soldering and therefore breaks the antenna circuit if is dislodged, I would look at that if a software solution is not helping. Most of us doing first time repairs were entirely unaware we'd lost it most likely when we first removed the motherboard's last screw under the ""Do not remove"" warning tape. I had no idea why my new screen worked so beautifully but I had a whole new problem of ""no service""! I tried everything and found no solution until this (thankfully someone figured out what no one else had)

Check for this component either missing or loose and/or damage to circuit traces in this area. Also check that the dock connector piece hasn't come apart at the seam and lost the spring loaded pin which is supposed to contact a small pad on the motherboard - too tight screws or the wrong screw can cause the board to bend just enough to break that contact because it lifts away from the pin also."

hi, here is what can be done to rectify the problem..iphone like any other phone is fragile....one need to be careful with it always....since your iphone dropped the possible problem that arrive from it is that..your iphone must have loose which cause no service problem..since sometimes the sevice we show up and later dissapear..look for a tech that knows well about the iphone and let them loose the iphone to the back side and tighten up any loose part....am sure this would work.