thisi is what you should do
To get to the service menu hold Power and Reset for 5 sec.
Passcode is MAP,MAP,MENU,Enter (center of joystick),MENU,Enter
Once in Service Menu the reset button is the only way of navigating. Short push move through options. Push and hold for 1/2 sec selects option.
got it from this thread
viewtopic.php?f=34&t=25838&p=175895&hilit=service+menu#p175895