A3 Cabriolet 2008 alarm keeps going off & boot open on dash

[cade]

Hi guys, apologies if this isn't the right forum. I recently got an A3 cabriolet a few months back and around 2 months ago the alarm started going off randomly in the night and it drained my battery and so I booked it in for a service and they installed a new boot lock and that was the end of it for a few weeks until now when it's started happening again. The general gist of it is that the car seems to think that the boot is open and that triggers the alarm every so often which drains the battery, and it seems to coincide with wet weather so I believe water must be leaking through (my boot is always a bit damp on the interior despite me drying it with a towel every so often) and triggering the alarm. For now I have bought a waterproof cover to keep on my car when I'm not using it to stop water getting through to it, but I was wondering if any others have had a similar issue and how they might have fixed it? I saw a thread here where someone had a similar problem but it was caused by their rear wipers leaking something to the locking mechanism, but since mine is a cabriolet that's not the issue for me.

[Steve Q]

Water in the boot I'd say could be coming from rear light seals, or bot seals where it meets the roof. Could it be the solenoid in the boot lock mechanism causing it to pop open I wonder? 

Has it had a further diagnostic check to see if any fault codes flag up since the initial repair? 

[cliffcoggin]

Rain is undoubtedly getting into the boot, and until that leak is found and cured no amount of new locks will resolve the recurring alarm problem. Finding the leak is not going to be easy and I am not familiar enough with the cabriolet to know of specific weak points, so all I can do is give general pointers.

Look at:

-boot lid seal,

-side/stop light seals,

-holes in the boot floor (rain can be thrown up from the wheels).