Skytec Astra alarm system just quit working unexpectedly

you will need to get a new remote most astra alarms 2 ways controls can be progam

Needs to be reprogrammed, system lost the match codes that go with the handheld. Two days was two days to long without power, system and the key fobs are not matched up.

Your Astra must have a backup battery, have to find the unit and disconnect the backup battery to stop siren

I would google your alarm system - include the model number. I googled just Astra car alarm system, and in the first page got this: http://www.commandocaralarms.com/manuals/a4000RSmanual.pdf But I don't know if this is your system or not.

I would google the Astra system - include the model number. I did a simple google and came up with
http://www.commandocaralarms.com/manuals/a4000RSmanual.pdf

but I have no idea if this is your system or not.

The batteries take a lot of power to send and receive data so you should get around 3 to 4 weeks per battery. If this is what you get it is normal.

Check the battery in your remote first. Then check all fuses for the Astra. Sounds like the main one at the battery.

may be a loose wire on the remote locking system, cheers

Hope this helps.
http://scytek.net/manuals/astra/a600.pdf

not sure about the astra but my mondeo had fault with alarm going off at random and it was the bonnet switch.

alarms check to see if any of the doors or boot ect.. are closed before setting and if it detects a fault then strange things happen like going off at random.