Driving the Roomster in light rain last night and the anti theft alarm horn started going off, this went on for around 6 miles, sometimes it would stop for a few seconds and restart. It was just the sounders and not hazard lights flashing.As quick as if started it stopped. Ond of my kids reckon my alarm went off this morning but had stopped before I heard it.

Does the door open warning light on the dashboard also come on at the same time?

No, no warning lights at all and the car still drove fine. Been out in it a couple of times since and it's fine. Just wandering if there was some rain water got in where it should not have.

Maybe wet in the push button that disables the interior alarm sensors, or is it the movement sensor?