Nokia Sprint PCS Vision 6165i User Manual page 199

When is my data connection dormant?
If no data is received for 10 seconds, the connection goes
dormant. When the connection is dormant, voice calls are
allowed. (The connection may become active again quickly.)
If no data is received for an extended period of time, the
connection will terminate.
Can I sign out of data services?
You can sign out without turning off your phone; however, you
will not be able to browse the Web or use other Sprint PCS
Vision services. While signed out, you can still place or receive
phone calls, check voicemail, and use other voice services.
You may sign in again at any time. To sign out, go to Menu >
Settings > PCS Vision > Disable PCS Vision in your phone's menu.
172 Section 3B: Sprint PCS Vision