Good day Brendan, Thank you for your quick reply. I am from QLD - Bundaberg. I am sure when I lock door, they are actually locked. Alarm goes off within 5-10 minutes initially but can happen at midnight too. Interior lights go out when I close doors. I think battery is 12v and I replaced the battery about 3 months ago because previous one was flat. This issues started about 6 weeks ago - it is bit cold in here Local toyota dealer said bring the vehicle back to remove internal door cover to see whether there is any loose connection - but I am worried to allow them to do it as I can not trust them fully. Kind regards