2000 8L Alarm Problem (Neighbours and Parents going Ballistic)

[j4ck100]

Hi all,

I know there is a lot on this forum already about this very problem but I have spent hours researching and troubleshooting and really want to know the most likely problem . Car is a 2000 reg Audi A3 8L 1.6 Standard Trim .

So basically it all started when I realised my car wasn't beeping after I locked it . About a month ago, I used vag-com to code in the car to beep when i locked it as i thought this was pretty cool. But just about a week ago it stopped beeping upon locking. A few nights later after this started, I realised at night the alarm would go off sporadically, even if I didn't lock the car. It has got to the stage now where the neighbours have complained to us. Today, I took the boot trim off the back and looked to see if the microswitch was wet as i hear this can be the problem. In addition , the rear washer doesn't work, but i beleive that it's now the joint under the subwoofer or around that location as the front and rear joints are fine. The micro-switch wasn't wet.

The alarm goes off in the day and night, but the indicators don't flash. To be sure it wasn't the microswitch, I unplugged it completeley to be safe. Nothing happened until around 10 minutes ago ( 12.30 am ) , the alarm just went off again ( car unlocked ) and I had to de-arm it.

I am now led to beleive that it is the siren or something causing the issue?

Can someone confirm that it is most likley this, and how I go about fixing (quick if possible).

In addition will disconnecting the battery stop the siren going off or is there a blade fuse i can pull out ?

Thanks in advance and sorry for the essay!

Jack

 

[Ste_Nova]

unplug the siren for now

then stick it on vcds and see what the last activations were

 

[j4ck100]

How do I view what activated the alarm ? I use vag-com and not vcds , and the car is x reg built 1999 pre-facelift . Also forgot to say i scanned the central locking module for faults and got something like alarm terminal 30 missing and central locking pump likely leak.

Thanks

 

[Tooks]

If you've checked all the switches etc, then it might be worth having a look at the siren itself, you'll need to get to it to disconnect it anyway?

It's most likely that the rechargeable batteries in the siren have gone, and started leaking over the circuit board in the siren. It will cause all kinds of weird issues/ghost activations etc.

Both my previous A3 and A4 had similar issues.

The repair for me both times was to remove the siren, open it up with a hacksaw blade, clean up the circuit board with contact cleaner etc, then replace the batteries with new rechargeable AA's in a suitable cage which I then fixed to the outside of the siren. There is a thread with pics over in the A4 B6 forum somewhere.

If the board is badly damaged, no spares are available, so it will be a new siren job.

 

[AndyMac]

Yes do a search this happens to all 8L's eventually (not sure where you spent your hours of research, but obviously not on here!), the backup batteries don't last forever! You need a new siren about £90 or do the well publicised DIY battery replacement