1999 Mercury Cougar alarm system malfunction? The alarm is going off irradically and it wont go off using the key fob. When you start it and drive some, it goes off, but when you turn the off, it goes off, again. Now it seems it goes off when the drivers door is opened.
With a WDS or IDS(scanners) the dealer could check what the door ajar switch is doing. Most likely the drivers door ajar switch is stuck. there is a recall for the door latch(NHTSA CAMPAIGN ID Number: 99V226000), I would call the dealer and check if it is on your car and as they replace the latch it should correct the issue.