Extension Mode - Casio Exilim W53CA Manual

The Safety Buzzer will sound through the W53CA's speaker while the
Casio round-type earphone jack conversion adapter 03 and the SONY
MDR-E0931, flat-type switched earphone microphone (option), or flat-
type stereo earphones microphone (option) is connected.
Even when Manner Mode is on, Safety Buzzer sounds.

Extension Mode

Using the Extension Mode, W53CA automatically shuts down the radio
wave after issuing the Low Battery Alert. This is quite a useful function
that you can still check outgoing/incoming records, content of e-mail,
address book, schedule and so on when necessary. In this case, you
can only use the functions which needs no radio wave.
To turn on Extension Mode
While the standby screen is displayed,
press c5321.
Display example when you switch to Extension Mode
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