Whops, sorry about my late reply, but Chris already beat me to it...
Mine was just flashing super fast - almost looked like it stayed on...
To fix mine, I had to hold the vallet button put the key in the ignition, push the door button (So it thought the door was closed) and turn the key to -on- (not ignition) then back off and fixed
I was shit scared to that I f'd the alarm but a quick read of the manual resolved my issue