Clio Alarm Problem

MY ALARM ON MY CLIO MK1 16V KEEPS GOING OFF ABOUT 3 TO 4AM, MAYBE 6AM AND IN THE MORNING FOR NO APARANT REASON.FED UP OF GOIN OUT IN NIGHT AND TURNING IT OFF. THE FUSE BLEW A FEW WKS AGO AND I REPLACED A NEW ONE. WENT OFF 5 TIMES LAST NITE IN AN HR,BETWEEN 12 AND 1AM.
IT IS A FACTORY FITTED ALARM WITH IMMOBILISOR.
DON'T THINK ITS THE BONNET SENSOR AND COLDNESS GETTING IN TO EFFECT THE SENSOR SO NOT SURE?
DOES THE ALARM NEED RESETTING MAYBE AND HOW DO I DO IT? :banghead:
ITS DRIVIN ME N NEIGHBOURS ABSOLUTLY MAD!
ANY IDEAS ATALL WILL HELP..
THANX