Motorola ic502 User Manual page 38

When a signal is found, your phone automatically returns to
standby mode.
In Power Save mode, your phone searches for a signal
periodically without your intervention. You can also initiate a
search for Sprint service by pressing any key (when your
phone is powered on).
Note: The Power Save feature helps to conserve your battery power
when you are in an area where there is no signal.
25 Section 1B: Your Phone: The Basics