If your iPhone 4 is suddenly showing “No Service,” it means you won’t be able to make or receive calls, texts, or use mobile data. That’s a big problem — but it doesn’t always mean your phone is broken. This issue can be caused by anything from a bad SIM card to a software glitch or network settings error.
Here’s how to troubleshoot and fix the iPhone 4 “No Service” error.
1. Make Sure You’re in a Coverage Area
Start with the basics: Is there signal in your location?
- Check other phones using the same carrier nearby. If they have service and yours doesn’t, it’s likely a phone issue.
- If everyone has no signal, there may be a carrier outage in your area. Contact your provider or check their website for service alerts.
2. Restart or Force Reboot Your iPhone
A quick restart can often fix temporary connection issues.
To force restart:
- Hold the Home button and the Sleep/Wake button at the same time.
- Keep holding until the Apple logo appears.
This resets your connection to the network without deleting any data.
3. Check the SIM Card
Sometimes it’s the SIM — not the phone.
- Power off your iPhone.
- Remove the SIM card.
- Wait a few seconds, reinsert it, and power the phone back on.
Still no service?
- Try using a different SIM (from the same or another network) in your iPhone.
- Or test your SIM in another phone.
If the issue follows the SIM, it may need replacing.
4. Disable Roaming if You’re at Home
Roaming should only be on when you’re traveling.
- Go to Settings > Cellular > Cellular Data Options.
- Tap Data Roaming and make sure it’s OFF if you’re not abroad.
5. Turn Airplane Mode Off (or Toggle It)
If Airplane Mode is on, you won’t be able to connect to a mobile network.
- Go to Settings > Airplane Mode.
- Toggle it ON, wait a few seconds, then turn it OFF.
This can help reset your wireless radios.
6. Reset Network Settings
If your iPhone’s network settings were corrupted or changed, this reset will bring them back to default.
To reset:
- Go to Settings > General > Reset.
- Tap Reset Network Settings.
- Enter your passcode and confirm.
This erases saved Wi-Fi passwords and VPN settings, but not your data.
7. Update Your Software (if possible)
Make sure your iPhone is on the latest available version of iOS for iPhone 4. You’ll need to use iTunes to check this since iOS 7.1.2 is the last supported version.
- Connect your iPhone to your computer with iTunes.
- Open iTunes and check for an update.
- Follow the prompts to install if available.
8. Perform a Factory Reset (Last Resort)
⚠️ Warning: This erases your iPhone completely. Backup first.
To reset using iTunes:
- Turn off your iPhone.
- Open iTunes on your computer.
- Connect your iPhone to the computer while holding the Home button.
- iTunes will detect a device in recovery mode.
- Click Restore > Restore and Update.
This reinstalls the software and resets the phone to factory condition.
Still No Signal? It Could Be a Hardware Problem
If none of the steps above worked, the issue may be hardware-related — possibly:
- A damaged SIM tray
- A faulty antenna
- A baseband chip issue (common in older iPhones)