Doors lock themselves and honk in the middle of the night
 

Hi
I know nothing about cars and I need you to help me with your knowledge.

During the night, my car started to lock its doors itself and, like when I click twice on my fob key to lock it, to honk. It would happen a few times and then stop. It would start over again later. I also noticed that my trunk was opened every time.

At the dealership, they said that it couldn't be an electric problem since no indicators were light up in the dashboard. They said that it might be a neighbour who has a fob key using same wavelength and that would look my car at the same time as his. This doesn't make sense: who would lock their car 50 times between 1:30AM and 9:00Am?

Is there anyone who has any idea of what could cause my car to lock itself up and honk?

Thank you ahead.

Hows your battery and/or battery cables? I had a similar issue with my Mazdaspeed Protege, but it didn't lock and unlock, the alarm would just go off for no reason.
It ended up being the battery cables. they were so corroded from the salt air (I live a block from the pounding surf) that they were almost gone completely. I couldn't even see the problem until I peeled off the rubber...um..end protector things.
I swapped out the terminals and solved my problem. The car has shut up at night, plus it starts up better and it may even be running a little better too.