# Alarm (siren) keeps going off and I can't stop it



## ModelCitizen (Apr 19, 2005)

Over the last three weeks my alarm (siren?) has gone off a number of times for no reason whatsoever whilst my car is sat in my (very quiet and entirely vibration free) drive. The beeping noise emits from the boot and the lights do not flash. I am not able to stop it and after a variable amount of time it seems to stops by itself. Today it went off whilst I was driving to work and it just would not stop. I have now left it in the multi-storey with it's battery disconnected.

Does anyone have any idea what's going on? My TT is 52 reg.

I've searched the threads here but not found anyone with exactly the same problem (although I have found out how to disconnect the alarm, which I may have to do this evening when I get the thing home).

Associated (and possibly misleading and not relevant info):

1) Yesterday I had the stereo on quite loud whilst the car was parked in my drive (whilst working on the house) and the battery went flat within an hour. I charged it up on fast charge overnight but am not sure that the lights on the battery charger registered as they should (i.e. it did not look as if it has become charged). However, the car started this morning with no problems. The battery is about 3 years old and looks fine (electrolyte levels are perfect).

2) A few days ago the key just started going right round in the ignition (barrel turning) without doing anything. Taking the key out and sticking it back in seemed to cure the problem

3) The little central switch that disables the interior alarm does not seem to do anything (certainly its light does not come on)

4) Using the key in the drivers door to disable the alarm (lock twice within a second) does not stop the sound

Any help very appreciated.

Simon


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## conlechi (May 6, 2006)

Hi Simon,
i had the same problem recently . It turned out to be the alarm siren itself . Quite an easy swap over but not a cheap part from Audi

Mark


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## __Dom__ (Jun 25, 2009)

Perhaps your battery needs replacing as I had the same problem ~ alarm just decided to go off one evening and I couldn't stop it. The internal sensor button didn't seem to work. Took it out for a short spin, which then cured the sensor button not working :? 
Anyway, shortly after this when there was a hard frost the battery ( it's a 53 ) died and was replaced. The problem has not reoccurred since...


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## Bikerz (Aug 23, 2008)

I place money its as Mark said. Rear light passenger side your find teh alarm box, unclip plug and 10mm bolt take out and I bet u it s a mess inside.


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## barton TT (Nov 13, 2004)

Just had a price from Northampton Audi for a Alarm Siren as mine is dead £79 +vat.


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## Mondo (Feb 20, 2009)

Yep, £72+VAT, or about £92 new from a dealer. Or maybe get one 2nd hand from eBay (possibly eBay Germany; they seem to have a few more) or from a wreckers like Nirro, like I did. £55 delivered; not bad except they sent an old-style one not the newer one they said they had and that I asked for... 

In the short term you could just unplug the fecker. Reach inside the boot panel on the left and just unclip the cable from it. Obviously won't go off if you're broken into but at least you'll get some [smiley=zzz.gif]


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## L13BUG (Dec 8, 2008)

i have the same problem at the minute and found this how to fix it
viewtopic.php?f=2&t=73315&hilit=alarm+siren


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## ModelCitizen (Apr 19, 2005)

Returning to my TT after work I reconnected the battery and the alarm started sounding straight away. Eventually I managed to disconnect the power to the siren and remove it.

The siren case looks fine. No corrosion.

I'm not sure what's best to do now. I don't want to splash out £80 on a new siren (or battery) only to find the problem continue.

Any suggestions or pointers would be much appreciated.

Cheers.

Simon


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## Wak (May 6, 2002)

Its almost a given that a new siren will fix this problem, however you could try to find someone willing to swap their siren into your car so that you can test it first.


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## Gone (May 5, 2009)

You might as well open it up, if you need a new one anyway you only stand to win. You'll have to cut along the seam around the outside of the case with a junior hacksaw, it's pretty soft plastic so quite easy. Just be careful when you strike through that you don't cut anything internally. Might be possible to fix a component or two.


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## ModelCitizen (Apr 19, 2005)

I've cut the siren apart and can see that one of the batteries is corroded. The acid had leaked a little onto the contacts and board but I've cleaned it off and all seems fine. The batteries are N3H 170 and appear to be for sale in the UK here: http://www.univercell-batteries.co.uk/c ... ue=N3H+170 ([email protected]).
I guess I'll find out on Monday.

Thanks all

Simon


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## Hoggy (May 8, 2002)

Hi Simon, Enquired before for those batteries from Universal, but told not avail any more.
Use these from Maplins as per John H "How To".
http://www.maplin.co.uk/Module.aspx?ModuleNo=30958
PCB NiMH 3/V150H..BN24B £6.49
Hoggy.


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## Bikerz (Aug 23, 2008)

L13BUG said:


> i have the same problem at the minute and found this how to fix it
> viewtopic.php?f=2&t=73315&hilit=alarm+siren


Normaly its destroyed the board. Mine had [smiley=argue.gif]


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## GilesRamsden (Nov 4, 2008)

All I can find to replace my batteries are N3H 170's instead of 160's.

Any ideas on direct replacements...?


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## GilesRamsden (Nov 4, 2008)

It's okay... the batteries I have found are the same, just a slightly higher capacity. Excellent.

Going to place an order from here tomorrow... http://www.univercell-batteries.co.uk/c ... value=nimh


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## Hoggy (May 8, 2002)

GilesRamsden said:


> It's okay... the batteries I have found are the same, just a slightly higher capacity. Excellent.
> 
> Going to place an order from here tomorrow... http://www.univercell-batteries.co.uk/c ... value=nimh


Hi, I contacted this Co. ages ago & those batteries were not avail anymore, so used the ones from Maplins. So let us know if things have changed.
Hoggy.


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## GilesRamsden (Nov 4, 2008)

How many of these Maplin batteries do I need to buy? Just the one...?


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## Hoggy (May 8, 2002)

Hi Giles, 2 of them, Maplin code is/was BN24. 3.6 volts 160MAH
Hoggy.


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## GilesRamsden (Nov 4, 2008)

Cheers bud.

Grimsby Maplins only has one in stock. Rubbish! :roll:


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