Motorola A780 Owner's Manual page 170

Problem
I pressed the
power key, but
nothing
happened.
The display
says:
Insert SIM Card or
Check SIM Card
even though I
have inserted
my SIM card in
the phone.
The display
says: SIM Blocked.
How do I
unblock my
SIM card?
The display
says: Enter Unlock
Code. How do I
unlock my
phone?
My phone
does not ring.
170 Troubleshooting
Solution
Be sure to open the flip, then press and
hold the power key P for 2 seconds,
until the display appears and you hear an
alert. If nothing happens, check that a
charged battery is installed (see
page 22).
The SIM card may be incorrectly
inserted. Check the SIM card to make
sure that it is inserted properly (see
page 20).
Call your service provider (the company
that sends you your monthly wireless
service bill) to obtain the PIN unblocking
key (PUK) code (see page 156).
Enter the factory-preset unlock code
(1234), or the last 4 digits of your phone
number. If this fails, call your service
provider (the company that sends you
your monthly wireless service bill).
Your phone may be set to a silent or
vibrate ring alert style. To change the ring
alert style, see page 146.