| I've got a similar thing with my wife's Hornet. Her switch is on the seat so as to protect the alarm unit, which sits under there. If I want to remove her seat, which would normally activate the alarm, I disarm the alarm as usual, and before it rearms, I remove the seat. The alarm then doesn't go off. I then either let the alarm rearm automatically, or rearm it myself, then press the large button. This puts it into ferry mode which means it's armed, but the motion sensor is disabled. Now I can fiddle under the seat or move the bike around. I use ferry mode whenever I clean it too as you can move the bike without the alarm going off, and you don't get the annoying service beep.
When I removed the battery the alarm did sound but I just pressed the disable button and it shut up.
Hope that helps. | 
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