I've tried it a few times too with no luck,the alarm wont respond to the fob,even with new battery so i just unplugged it all. Couldn't get the box out.
From my own observations, it seems my 1999 Coupe 20VT will ignore the fob, if you lock the car with a key, but responds again after unlocking with the key. An unusual anomaly that I've yet to get the details about, although my latest acquistion came with a full set of physical workshop manuals.
Tee hee (or fnar, fnar, if you prefer).