My '04 S40 (second model) Security Alarm is going off, without being triggered by a break in.

I had this issue a few years ago, and the dealer/service said they didn't see anything wrong with it, and the computer didn't give them any clues.

Lately it's started doing it again, including twice last night, once around midnight, and once around 3AM. It's parked at night on a quiet residential street, and I'm sure my neighbors were thrilled with me.

After the second event, I just left it unlocked.

My dealer/service is an hour away. I wouldn't mind the trip if I were confident they can take care of it.

Is this a common Volvo issue?

Can the thing just be disabled?

Any clues as to what causes this, and what the cost of fixing it might be?

Is this likely to be one of those gremlins with a number of possible causes, that will result in me making multiple trips to the dealer?

thanks,

Dan