45TroubleshootingTroubleshootingIf you experience any trouble while using the unit, refer to theinformation in this section for troubleshooting. See the ReferenceManual (tap [Online Manual] in the app list) for additionaltroubleshooting information.Starting upThe unit does not turn on.• To turn the unit on, press and hold (power button) until the unitbriefly vibrates.• The battery may have become completely discharged. Chargethe battery.• The unit may be too hot. Leave the unit in an environment of10 °C to 35 °C (50 °F to 95 °F) for about an hour, and then tryagain.• The unit may be too cold. Leave the unit in an environment of10 °C to 35 °C (50 °F to 95 °F) for about an hour, and then tryagain. After turning on the unit, you can enable the heater so thatit will turn on automatically if the unit becomes too cold. See“Enabling the internal heater” (page 50).The unit does not wake up from sleep.• The battery may have become completely discharged while theunit was in sleep mode. In this case, any data which has not beensaved will be lost, and the unit will not wake up. Charge thebattery.• The unit may be too hot. Leave the unit in an environment of10 °C to 35 °C (50 °F to 95 °F) for about an hour, and then tryagain.• The unit may be too cold. Leave the unit in an environment of10 °C to 35 °C (50 °F to 95 °F) for about an hour, and then tryagain. After turning on the unit, you can enable the heater so thatit will turn on automatically if the unit becomes too cold. See“Enabling the internal heater” (page 50).