I am trying to replace the battery on my 986. When I disconnect the negative lead, after about 5 seconds, the alarm sounds for 30 seconds (hell, that thing's loud!). It continues to sound even if I disconnect the positive. I can't find any reference to this anywhere. Is it possible to do something to prevent the alarm activating when changing the battery, or am I just going to have to deafen myself and annoy the neighbours?