Fujitsu Ten ECLIPSE OWNER'S MANUAL / CD3200
Check that the power of the main unit is in standby.
While pressing button [4], press the [SCREEN/TEXT] button, and hold
both for more than one second.
After the "ESN" message appears on the display, an 8 digit number will appear. This number is the Electronic Serial Number (ESN) of the device. You may use this number to identify your Eclipse CD3200 in the event of theft recovery.