Check the alarm switch under the bonnet. Tape it down or put a piece of cardboard on it to make sure it's pushed right in when the bonnet's closed.
Has the alarm been giving little 'beeps' over the past few weeks? If so it could be the battery in the power-sounder failing. It's not practical to replace the battery, you need a new unit.
It might be easiest to get the alarm activation history codes read. You dont have to go to the Vauxhall dealer, lots of garages, auto electricians and alarm fitters can do it cheaper.
victor
April 2009
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