from your device. Try entering the code onlyonce, if you forget the code. If the code youentered is not correct, contact a Nokia Care pointor your service provider for further instructions.● Personal unblocking key (PUK) code and PUK2code — These codes (8 digits) are required tochange a blocked PIN code or PIN2 code,respectively. If the codes are not supplied withthe SIM card, contact the operator whose SIMcard is in your device.● UPUK code — This code (8 digits) is required tochange a blocked UPIN code. If the code is notsupplied with the USIM card, contact the operatorwhose USIM card is in your device.Prolong battery lifeMany features in your device increase the demandon battery power and reduce the battery life time.To save battery power, note the following:● Features that use Bluetooth technology, orallowing such features to run in the backgroundwhile using other features, increase the demandon battery power. To prolong the operating timeof your device, turn the Bluetooth technology offwhen you do not need it.● Features that use wireless LAN (WLAN), orallowing such features to run in the backgroundwhile using other features, increase the demandon battery power. WLAN on your Nokia deviceswitches off when you are not trying to connect,not connected to another access point, or notscanning for available networks. To furtherreduce battery consumption, you can specify thatyour device does not scan, or scans less often, foravailable networks in the background. WLANswitches off in between background scans. See"Wireless LAN", p. 33. When Scan fornetworks is set to Never, the WLAN availabilityicon is not shown in the standby mode. However,you can still manually scan for available WLANnetworks and connect to WLAN networks asusual.● If you have set Packet data connection toWhen available in connection settings, andthere is no packet data coverage (GPRS), thedevice periodically tries to establish a packetdata connection, which causes increaseddemand on battery power. To prolong theoperating time of your device, select Packetdata connection > When needed.● The Maps application downloads new mapinformation when you scroll to new areas on themap, which increases the demand on batterypower. You can prevent the device fromautomatically downloading new maps. See"Maps", p. 93.17 Useful information
