Calls and connection issues
Welcome
Check signal
Make sure Airplane Mode 
is turned off. To turn off Airplane Mode, tap Settings > Airplane Mode.
Check the top left corner of iPhone's display to make sure you have a strong signal 
. If not, try changing your location or going outside.
If you're not using Wi-Fi and you're trying to access the Internet, make sure you have a cellular data connection by checking next to the carrier name at the top of the screen for one of the following indicators:
UMTS/EV-DO
EDGE (GSM models only)
GPRS/1xRTT
or one of the cellular data network icons to the right of your carrier name if iPhone has an active network connection. If you are using Wi-Fi, you won't see a cellular data network indicator unless you turn off Wi-Fi. To turn off Wi-Fi, tap Settings > Wi-Fi.
Reset network settings
To reset your network settings, tap Settings > General > Reset, then scroll down and tap Reset Network Settings.
Note: This will clear your current cellular and Wi-Fi network settings, including saved networks, Wi-Fi passwords, and VPN settings.
Reposition SIM card
Step 1: Remove the SIM card by inserting the end of the SIM eject tool, or a small paper clip, into the hole on the SIM tray.
Step 2: Press firmly and push it straight in until the tray pops out.
Step 3: Gently remove the SIM card from the tray, then reposition the SIM card back in the tray.
Step 4: Return tray to iPhone, then push to fully reinsert.
Update preferred roaming list
Verizon, Sprint and C Spire customers only.
If you are experiencing call quality or connection issues, you can update your preferred roaming list by dialing *228 from your iPhone. Please contact your carrier for more information.
Check carrier
For questions about network status, coverage area, billing, and other related issues, get help from your carrier.
Restore iPhone
To restore your iPhone, first make sure you are using the latest version of iTunes.
Next, connect iPhone. In the left column under Devices, click on your iPhone, then click on Restore in the Summary tab.
For more information about backing up, updating, and restoring your iPhone software, see this article.
If iPhone still has call and connection issues, try the following options:
- Get tips from fellow iPhone users at our iPhone Support Communities.
- Use Express Lane to get advice from experts who know your product best. Talk to us now or later at your convenience.
- If you live near an Apple Retail Store, make an appointment with a Genius.
- Print and complete this helpful page to expedite your call or Genius Bar visit (where available).
- If you have an iPhone 4 and are experiencing antenna or reception issues after completing the troubleshooting steps, please contact an Authorized iPhone Service Provider listed in this article to request a free black iPhone 4 Bumper.
