The phone will not turn on, or the phone switches itself off
Below are some helpful tips for what to do if you can't turn your phone on. Be sure to try each one to determine the nature of the problem.
First, make sure your battery is fully charged. If the battery is drained out, it may take up to 30 minutes of charging before the battery-charging icon appears on the screen.
Press the On/off key for a minimum of 10 seconds to turn the phone on.
If your phone has a memory card, remove the memory card and try to power the phone on. If the phone turns on, you might need a new memory card.
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Sometimes, you need to remove the battery to clean dust, dirt and corrosion from the connectors on both the battery and the phone. You can clean the connectors with a soft brush, cloth or q-tip moistened with any type of unflavoured, colourless alcohol. Check that the connectors of the battery and the phone are totally dry before you put the battery back in the phone.
Also, check for damage to the connectors of the phone. If you have an original Sony Ericsson battery and your phone displays an alien battery message, cleaning the battery as described above might help you correct the problem.
If possible, try your phone with another battery. If the phone turns on, you might need a new battery. Before replacing your battery, make sure your charger works properly.
Run Update Service regularly for optimal performance and to improve software stability.