Specifications

iPhone 4 Symptom Charts — Connectivity Issues 64
2012-02-21
3. Test known-good Bluetooth
accessory.
Attempt to pair device with
a known-good Bluetooth
accessory. Test for accessory
functionality.
Does the device function as
expected with a known-good
Bluetooth accessory?
Yes Issue resolved. Bluetooth accessory is
not functioning as expected. Refer user
to manufacturer for support.
No Determine if the issue is caused by
accidental damage. Refer to the Visual
Mechanical Inspection guidelines.
Cellular Call/Text Issues
Known-Good Parts & Materials Required: SIM card, SIM removal tool, Dock Connector to USB
Cable, computer running the latest version of iTunes with a known-good USB port
Also see Apple Support articles:
• HT1976: iPhone: Understanding cellular data networks
• HT3529: iPhone: About SMS and MMS messaging
• TS2755: iPhone: Troubleshooting MMS
• HT2417: iPhone: Troubleshooting voicemail issues
Quick Check
Symptoms Quick Check
• Cannot make or receive calls
• Cannot send or receive text
messages
1. On the device, go to Settings and turn Airplane
Mode on for 15 seconds, then o. This resets all
wireless connections on the device.
2. Restart the device.
3. If the device is in a case, remove it from the case.
Power o (red slider) and back on. See Apple
Support article HT2342: iPhone: Signal or other
interference while in carrying case.
4. If there is not at least one bar of cellular signal
strength, try moving to another location and
check for a better signal.
5. For text messaging, make sure that the area code
is included with phone numbers in the contacts
list.