Settings
[Menu
9]
Security settings [Menu 9-5]
PIN code request [Menu 9-5-1]
In this menu, you can set the phone to ask for the PIN code of your SIM card when the phone is switched on. If this function is activated, you’ll be requested to enter the PIN code.
1.Select PIN code request in the security settings menu, and then press 
[Select].
2.Set On/Off.
3.If you want to change the setting, you need to enter PIN code when you switch on the phone.
4.If you enter wrong PIN code more than 3 times, the phone will lock out. If the PIN is blocked, you will need to key in PUK code.
5.You can enter your PUK code up to 10 times. If you put wrong PUK code more than 10 times, you can not unlock your phone. You will need to contact your service provider.
Phone lock [Menu 9-5-2]
You can use security code to avoid unauthorized use of the phone. Whenever you switch on the phone, the phone will request security code if you set phone lock to “On”. If you set phone lock to “Automatic”, your phone will request security code only when you change your SIM card.
Automatic key lock [Menu 9-5-3]
When you enable Automatic key lock, keypad will be locked automatically on an idle screen after 30 seconds without any key requesting.
75 G1610 User Guide