Master Reset
Set the watch to factory defaults settings and delete changes you have made.
To reset the watch
1) Enter pairing mode
2) Press and hold the right top and bottom key until the display lights up. After a few seconds the display dims again and you watch is reset.
User Guide:
http://www.sonyericsson.com/cws/support/accessories/detailed/userguide/mbw-150classic edition?lc=en&cc=gb
