I have a 04 streetka and have problems with the alarm. It started when i unlock the car and open the door the alarm would go of for about 5 minutes then stop, As soon as i open the door it would go off again so in the end i would lock the car and leave it till the next day and it would sort itself out. now i can get into the car no problem but when i start it up the alarm goes off, when i switch the engine off it stops HELP any ideas ( had to drive back from the shops with alarm sounding)