TroubleshootingGeneral informationIf you experience any trouble while using the unit, refer to the information in this section for troubleshooting.If the problem persists, contact your technical support representative.Starting upThe unit does not turn on.• To turn the unit on, press and hold (power button) until the unit briefly vibrates.• The battery level may be low or completely discharged. Charge the battery.• The unit may be too hot or too cold. Leave the unit in an environment of 10 °C to 35 °C (50 °F to 95°F) for about an hour, and then try again.The unit does not wake up from sleep.• The battery may have become completely discharged while the unit was in sleep mode. In this case,any data which has not been saved will be lost. Charge the battery.• The unit may be too hot or too cold. Leave the unit in an environment of 10 °C to 35 °C (50 °F to 95°F) for about an hour, and then try again.Nothing appears on the screen.• The unit is in sleep mode. Press (power button).• Charge the battery.• Install the battery correctly.• Replace the battery with a fully-charged one.• The screen is too dark. See “The screen is too dark.” (page 45).Other startup problems• Disconnect and remove all peripheral devices.Shutting downThe unit does not turn off.• It may take one or two minutes for the unit to turn off. This is not a malfunction.• Press and hold (power button) for at least 10 seconds to force the unit to restart, and then tryagain.• Disconnect and remove all peripheral devices.ScreenThe screen is too dark.• The [Adaptive brightness] setting reduced the brightness according to the ambient brightness.Manually adjust the screen brightness.1. Swipe up the home screen, and then in the app list, tap [Settings] ® [Display].2. Tap the [Adaptive brightness] switch to turn it off.3. Tap [Brightness level] and then adjust the slider.Operating Instructions - Reference Manual 45Troubleshooting