Charging your iPhone

• If your iPhone is not turning on and flashing a red battery icon, the battery's power is critically low. When the iPhone reaches this state, it must be charged for at least 10 minutes before you can use it. Connect your iPhone to your computer using the USB cable or the USB cable with the AC plug to automatically begin the charging process. In a few seconds, the charging icon will appear on the phone's screen. If you're using a notebook, you may need to disable sleep or hibernation mode or the iPhone won't charge. It may take about four hours for the iPhone to fully charge. When the iPhone is fully charged, the "Charged" message appears on the display.
  
  

Troubleshooting

• If your iPhone isn't charging, try restarting it by pressing the "Sleep/Wake" button, sliding the red slider until it turns off and pressing the "Sleep/Wake" button again until the Apple logo appears on the screen. If the battery problem persists, press and hold the "Sleep/Wake" and the "Home" button for at least 10 seconds or until the Apple logo appears. If you're using a notebook to charge your iPhone, make sure it's connected directly to an USB port on the system and not a hub or USB port on a keyboard. If the device still won't charge, you may have to reset it with iTunes, but keep in mind that restoring the phone erases saved content, so always back your files.
  
  

Tips and Recommendations

• Operating your iPhone within reasonable temperature can improve the lithium battery's performance and possibly increase your iPhone's lifespan. According to Apple, operate your iPhone in a place where the temperature is between zero and 35 degrees Celsius (32 to 95 degrees Fahrenheit). Low or high temperatures below or above the acceptable range may shorten battery life. If a temperature warning appears on the screen, it means the internal temperature of the device exceeds normal operating temperatures, so let the iPhone cool down.
  
  

Warnings

• Apple states that rechargeable batteries have a limited number of charge cycles and may eventually need to be replaced. If your phone's battery is dead, replacing it can be a difficult task that can damage your phone, so attempting to fix it yourself may not be the best idea. You risk damaging it further it you make a mistake. Contact Apple support for additional troubleshooting and repair may be necessary. If your iPhone is still under warranty, tampering with it may violate the warranty and force you to pay out-of-pocket for repairs.