My alarm sounded off for the first time last weekend, yep memorial day weekend of all times.
I read through all of the posts, thought maybe the battery. I checked the battery to find that it was the original on a 2004 coupe. I went on memorial day and had a new battery put in. Everything was peaceful until today when I was heading out to my XF to hear that anoyance of an alarm screaming. I had to wait for it to run it's full cycle as the key fob couldn't shut it up. I wrapped the key fob, that I normally carry with me, in aluminum foil to block any odd rf signals that may be transmitted from the fob to find that the alarm sounded off again. This time the backup fob did turn off the alarm. I've only had the car for a little over a month. Love the car but hate the alarm acting like it is. Any suggestions for possible fixes, short of tearing the car apart, would be greatly appreciated.