Does it look like this
http://abacuscaralarms.co.uk/alarmsh...d&productId=97 If so it's a Meta Alarm
http://www.metasystem.co.uk/index.ph...g-Instructions I don't think they have a service mode. They do have a ferry mode which disables the movement sensor. Press and hold the button down and you will get some extra lights and beeps to say it's activated