Alarm on car goes off for no apparnt reason night and day. I have tried closing air vents. I also cannot turn alarm off by locking car with turning key twice as vw handbook says. Is there anyone who can help.VW passat 1.9tdi (2003(53) Many thanks in advance paul mail

Hi, passats of your cars year suffer from water leaking into the car from the heater inlet ducting mounted forward of the windscreen on the N/S. This contaminates a number of multiplug wiring connections mounted inside the car to the left of the passenger side footwell (behind the plastic kickpanel). Remove the panel and inspect each of the multiplugs by pulling them apart. Any connections affected buy water ingress and corrosion should be cleaned with contact cleaner and treated with water repellant spray (WD40 etc). To affect a permanent repair the heater ducting/inlet box will need to be removed and sealed - probably a garage job.
Hope that helps Matt...