LG G5400 User Manual page 115

You can use the access codes described in this section to avoid
unauthorized use of your phone. The access codes (except PUK
and PUK2 codes) can be changed by using [Menu 4-5-5].
The PIN (Personal Identification Number) code protects your SIM
card against unauthorized use. The PIN code is usually supplied
with the SIM card. When is set , your phone will
request the PIN code every time it is switched on. On the contrary,
when is set , your phone connects to the network
directly without the request PIN code.
The PIN2 code, supplied with some SIM cards, is required to
access some functions such as Advice of call charge, Fixed Dial
number. These functions are only available if supported by your SIM
card.
The PUK (PIN Unblocking Key) code is required to change a
blocked PIN code. The PUK code may be supplied with the SIM
card. If not, contact your local service provider for the code. If you
lose the code, also contact your service provider.
The PUK2 code, supplied with some SIM cards, is required to
change a blocked PIN2 code. If you lose the code, also contact your
service provider.
The security code protects the unauthorized use of your phone. It is
usually supplied with the phone. This code is required to delete all
phone entries and to activate "Reset settings" menu. The default
number is .
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