Toyota 2006 Prius Owner's Manual page 223

(v) Setting the security
When you set the security, you can pre-
vent people from using some functions
of the hands−free system. It is useful
when you leave your car with the hotel
or you do not want others to see the
data you registered.
When you set or unlock the security, you
have to input the security code. Be sure
to change the default code when you use
the security for the first time.
D
Changing the security code
The security code is 4 digits and the
default is "0000".
Choose a new code that is hard for other
people to know.
When you change the security code, do
not forget the code. The dealers cannot
unlock the security when you forget it.
If you forget the security code, initialize
your personal data. (See "Initializing the
security code" on page 225.)
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1. Touch the "Phone Book
switch.
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2. Touch the "Change" switch.
Lock"
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