Alarm System

I recently (August 2014) purchased a 2010 Ford Escape, with only 16,500 miles. I was told the previous owner had only had the car for 6 months, she had purchased it from their dealership but wanted to trade it in on another (Chevy) car because the alarm kept going off for no reason. (She was a nurse and while at work, at the hospital, the alarm would just go off and disturb everyone - and especially her! – So the dealer said they had taken it to a Ford dealer and they couldn’t make it go off, so they thought it might be the keys. So my salesman said they had new keys made for the vehicle and it hadn’t had the trouble anymore. We bought the SUV. The first night home, the horn starts blowing at 3 in the morning - while the car is sitting in our garage!! and it has gone off several times while I’ve been at work. I’ve had it to my local Ford dealer and they thought it might be a back door latch, but can’t tell which one.
What should I do? Have all the door latches changed? Or could it be something else??? Help me with this honker!!!

Cats?

Do the interior lights go on and off as you drive? If not, I don’t think the problem is with the door switches. The problem may be with an inertia switch active only when the alarm is on.

Is tere an after market anything on the car? PS I think there may be a fuse for that.

On one of my Ford forums, low battery voltage can cause the alarm to go crazy. Has the battery been load-tested?

Some newer cars have two separate circuits, one for keyless entry another for courtesy lights. With the doors locked try to open each one, also cycle the door locks and look to see that they all move lock to unlock completely. Door lock actuators do fail on occasion.

Thanks for all the comments. I have called Ford and they called my dealership and told them to get it fixed. I made an appointment on Saturday, they run a diagnostic and it just gave an update. They tried bypassing the back door latch. The alarm went off at 7:20AM Sunday morning! So I went back Monday morning and they gave me a loaner to drive, hoping it will “sound off” while they have it. We’ll see…

I’ve said this many times before but I will say it again: “Most alarm systems are nothing more than a way to disrupt sleep in the neighborhood at 3 in the morning.” No one pays any attention to a vehicle with it’s alarm blaring and lights flashing other than to be annoyed.