# *beeping* alarm



## sightlesseyes (Jul 23, 2010)

Hi everybody, I've been reading these pages for a little while now and I'm now contributing through necessity!

Today the alarm sounder (near the boot) has started beeping at seemingly random times. What makes it all the more worrying is that it's not stopped by the remote, or the engine starting.

I have replaced the battery in the key fob but this hasn't worked and it took to only starting beeping after the engine had started tonight. Is there any light anyone can shed on this before I have to shell out some major money and send it to audi?

Many thanks peoples

John


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## SteviedTT (Apr 10, 2009)

Sounds like it's the batteries in the alarm unit itself mate. There's a post on the forum somewhere about how to change them. I'll have a search and see if I can find a link for you.


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## Hoggy (May 8, 2002)

Hi John, Welcome to the TTF. It may be the batteries in the alarm have failed, leaked & shorting out the PCB. Remove passenger side rear light & disconnect the plug. Here is a "How To" repair from John-H.
viewtopic.php?p=792942#792942
Hoggy.


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## BlackBlur (Mar 29, 2010)

Hoggy is right but as they are just starting to sound its likely they are just flat and not at the stage of leaking... a new unit is around £90 if you want a new one


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## peter-ss (Sep 3, 2008)

It's common for the rechargeable batteries inside the alarm siren to leak and damage the curcuit board.

As a result of the leaking batteries my siren packed up completely so I replaced it with a new one from Audi costing about £70.

It may be possible to crack the siren open and replace the batteries but if they've caused further damage inside then replacing it is probably the easiest option.

I seem to remember that I had to drill out the bracket that it mounts to when I changed mine as the updated version of the siren has a slightly larger mounting bolt, you'll also need a larger nut to suit.


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## SteviedTT (Apr 10, 2009)

Beat me to it guys, I'll get the hang of this search engine one of these days


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## BlackBlur (Mar 29, 2010)

peter-ss said:


> It's common for the rechargeable batteries inside the alarm siren to leak and damage the curcuit board.
> 
> As a result of the leaking batteries my siren packed up completely so I replaced it with a new one from Audi costing about £70.
> 
> ...


Correct... forgot about that


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## Hoggy (May 8, 2002)

Hi, 12 mm bolt on new one can just be prised/slid out & a 10 mm bolt slid in. That's what I did easier than drilling out bracket.
Hoggy.


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## steve180bhp (Dec 26, 2007)

try this ,its not as hard as it may appear. Its a lot cheaper than replacing the whole thing, did mine about 2years ago and still works great. viewtopic.php?p=792942#792942


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## sightlesseyes (Jul 23, 2010)

Thanks for all the responses people, I knew there'd be a solution but I didn't expect it this quick! I'll get a new sounder and fit it, I think. The repair doesn't look to complicated but I've not held a soldering ironm since school and I wouldn't like my first time back out to end up costing more than it has to. Is it just Audi garages I can get the sounder from or is there a VAG stockist that may be cheaper?

Thanks again for all your help!


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## BlackBlur (Mar 29, 2010)

Audi will probably be your best bet, i havent seen / heard of anywhere else that will or do stock them


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## sightlesseyes (Jul 23, 2010)

Curiously, the alarm beeping has ceased. When it originally happened on the Friday I intended to buy a new unit on the Monday but it had no relapses after the following Saturday.

Still beeping fre but I've got that fix to fall back on if it does start again.

Thanks again for all the help people.


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## T3RBO (Dec 9, 2003)

If the siren has stopped beeping then the batteries inside have probably died. Try testing the alarm by leaving a window open and activating it, then wave your hand inside the car to see if it goes off :wink:


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## techfreak (Aug 13, 2010)

T3RBO said:


> If the siren has stopped beeping then the batteries inside have probably died. Try testing the alarm by leaving a window open and activating it, then wave your hand inside the car to see if it goes off :wink:


thanks for this little test, as id just realised theres no alarm beeping when locking/unlocking ...

tried this, and hey presto, alarm goes off but no siren.....gonna try johns fix and check if the battery hasnt knackered everything in its path, or just replace it myself.


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## T3RBO (Dec 9, 2003)

The alarm only beeps on lock/unlock if you have that featured activated via vagcom :wink:

Good luck with the repair mate.


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## techfreak (Aug 13, 2010)

T3RBO said:


> The alarm only beeps on lock/unlock if you have that featured activated via vagcom :wink:
> 
> Good luck with the repair mate.


ahh, good idea, do you knw the code to do this? may as well whilst im at it!
_ok - just found a list of recodes on waks site, but this states they're for north america? do they work here? nice touch to get the windows going up too..._

also, before i go checking the alarm, could it be a fuse? if so how can i test this? voltage test?


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## SOFTTY (Aug 9, 2007)

quickest fix get new one went through the trouble off spliting old one but to far gone


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## techfreak (Aug 13, 2010)

yea think thats what im gonna do....just get a replacement unit, can pick em up for about £40.00 so its not too bad...gonna try a scrappy see if i can get em cheaper....


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## hooley (Dec 30, 2008)

techfreak said:


> yea think thats what im gonna do....*just get a replacement unit, can pick em up for about £40.00 so its not too bad*...gonna try a scrappy see if i can get em cheaper....


Where can you get one for 40 notes?
TPS?

Cheers
Jason


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## techfreak (Aug 13, 2010)

hooley said:


> techfreak said:
> 
> 
> > yea think thats what im gonna do....*just get a replacement unit, can pick em up for about £40.00 so its not too bad*...gonna try a scrappy see if i can get em cheaper....
> ...


german ebay, theres a guy who's got a buy it now for £26.00 pounds odd + 13.90 euro shipping...so thats about there or there abouts...also trying some parts places/breakers


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## hooley (Dec 30, 2008)

techfreak said:


> german ebay, theres a guy who's got a buy it now for £26.00 pounds odd + 13.90 euro shipping...so thats about there or there abouts...also trying some parts places/breakers


I feel a Group Buy coming on
Anyone?

J


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## hooley (Dec 30, 2008)

Hmmmm

Will the Mk2 siren match the plug of the Mk1??

Anyone?

J


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## Mr Grinch (Mar 20, 2021)

Bring this to the top out of desperation !

If you look at my other threads i took the TT in for the siren unit to be changed as it wasnt working a causing a battery drain. So far so good. The siren changed with a genuine audi part that is new. The good news, the siren works BUT during testing when the car was locked and left and even when open, the siren unit continuously beeps. Not loud but beeps. The garage hooked it up snd the fault reader said it was a communication error with the part. Obviously cant be left on as it really would drain my battery so the old one put back in but not connected. 
Has anyone any experience of this and wondered fix wise its not going to cost a fortune. The garage warned that it could be easy to find or it could take hours. At £80 an hour it could be very expensive. Trying to decide whether to cut my losses and leave it although i have a brand new Siren to get rid of as Audi wont take returns on used items. 
HELP !!!


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## silverbug (Jan 1, 2020)

As I may have posted on one of your previous posts (can't remember :lol: ) make sure the wiring going to and from the siren is 100% electrically conductive.
I had to replace all 3 wires well into the boot space (I had all the boot trim panels out tracing the route of the wires) and I had to keep on cutting into the loom until I didn't find that the copper wires were blackened inside the pvc outer covering .
When the wires were blackened because of the creeping corrosion caused by the leaking siren batteries they were impossible to solder.
I had to replace about 2 feet or so of loom .
Only when I had spliced nice new wire into the loom did I have communication with the siren and it worked the minute I plugged a second hand working siren into it.
Even if you fit a brand new (working) Audi siren , it's likely to have sat around for quite a long time so I'd say that you should let it sit for a few days to fully charge up from the car battery.......so I wouldn't necessarily be too concerned about it beeping initially .


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## PlasticMac (Apr 25, 2017)

Look at the date code on the new siren. Since battery life is around 8 years less if left uncharged, on the shelf, I'd ask the dealer to reconsider the price they charged you, unless it is under a year or so old. Sale of goods act etc.
Mac.


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## Mr Grinch (Mar 20, 2021)

Will look into it. Could it just be the battery not charged to capacity ?


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## PlasticMac (Apr 25, 2017)

Mr Grinch said:


> Will look into it. Could it just be the battery not charged to capacity ?


Quite possibly, yes. My point is, if I bought a new part, with an integral battery, in 2021, it should last around 8 years or so. If the date code on yours is, say, 2010, then it's knackered already. An NiMh battery, left connected to a circuit, for 10 years, will not last long, and will, probably, never charge fully.
It's also very important to check the condition of the wires from the connector, as others have said. 
Mac.


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## Mr Grinch (Mar 20, 2021)

Ive spoken to them and they saw no corrosion. I do not know the part date so cant comment but i do understand. Would be good to know though if the beeping was because it was charging. Doesnt explain the hook up saying communication error though.


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## davebowk (Aug 16, 2019)

They normally beep to let you know the battery is knackered


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## PlasticMac (Apr 25, 2017)

The siren is self powered, solely from the battery. Although the car charges the battery, it does not power the siren itself. If the battery is not charged, the siren circuit will not communicate with the ecu (hence comms failure), and it beeps to tell you that it is not functional.
So, unless the beep stops and comms is restored soon (the battery is not high capacity, and, if in good nick, will charge quickly), your new siren is duff.
Mac.


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## Mr Grinch (Mar 20, 2021)

I managed to return the part to Audi thanks to the chap who had contacts there. The old one put back in but not connected. The drain is now down from 40ma to 20ma. Think i will just leave it. I dont really need it and may open up a can of worms


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## Mr Grinch (Mar 20, 2021)

Interesting thanks. Instead of the new siren being naff, could it not be a wiring issue? The battery not being charged because of that instead of the battery ? Coroded plug in or broken or loose wire ?


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## davebowk (Aug 16, 2019)

It could be.
You have 12v a ground and com/signal wire.
You should have 12v when the cars off. Mine did as i blew the fuse when i cut the plug off to replace it.
Check the 12v and the ground wire. Don't know where the coms wire connects to, can't find it on the diagrams.
But if the drain has reduced it does sound like you have 12v to the unit and the unit battery was goosed.


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## PlasticMac (Apr 25, 2017)

davebowk said:


> It could be.
> You have 12v a ground and com/signal wire.
> You should have 12v when the cars off. Mine did as i blew the fuse when i cut the plug off to replace it.
> Check the 12v and the ground wire. Don't know where the coms wire connects to, can't find it on the diagrams.
> But if the drain has reduced it does sound like you have 12v to the unit and the unit battery was goosed.


I reckon there was 12 volts to the siren, because there was enough in the battery to sound the beep.
So, yes the drain was, as Dave says, the car trying to charge a dead battery.
Mac.


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## Mr Grinch (Mar 20, 2021)

Im getting lost.
The drain was when the old knackered unit siren was on. When the old was disconnected, the drain reduced by 20ma. The car now drains at around 15ma which is tiny, so im now not concerned about that.
My question was when the new Siren unit was fitted which was bought direct from Audi. The thing beeped continuously although when tested to see if the siren would be set off (window open wave arms inside and bang seats) the siren activated as it should. But when the car was reset, the thing beeped even when in use and even when locked up. 
So a few questions:
1. Could it be a faulty new siren ?
2. Could it be a software issue ?
3. Could it be a faulty wire some where in the car ?
4. Could it be making the noise because its being charged and the garage has not left it long enough to see if it will stop?
As it stands, luckily Audi have taken the siren back with a bit of blagging so im only out of pocket for the work and investigation done which was not massive. The old siren has not been connected back up but is in place. To be honest, if the answer is a wiring issue or software problem then its not worth the money thats going to be spent on investigations. The car as it is, is perfectly fine, just no alarm siren and thanks to it being disconnected now has less of a battery drain.


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## silverbug (Jan 1, 2020)

When I repaired my corroded wiring and replaced my alarm siren with a secondhand unit last year it worked when testing the alarm straight away.
I seem to remember though that with the car at rest and with it locked and alarmed there was a muted beeping for a few hours which then went away.
I put this down to the siren internal batteries possibly being in a state of discharge when the siren had been fitted to the car and after a few hours the siren batteries had been charged by the car....
If I'm right or not , I don't know but it hasn't beeped since and still works fine 15 months later.


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## Stustt (Jul 3, 2020)

Sounds right what silverbug says. An audi alarm siren out of the box battery would be dead flat.
Would take quite a few hours to charge up so likely to make muffled noises till then.
When you activated alarm it would run off the main battery. The siren battery is for if a thief disconnects main battery ie it's a back up system.


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## PlasticMac (Apr 25, 2017)

Mr Grinch said:


> Im getting lost.
> The drain was when the old knackered unit siren was on. When the old was disconnected, the drain reduced by 20ma. The car now drains at around 15ma which is tiny, so im now not concerned about that.
> My question was when the new Siren unit was fitted which was bought direct from Audi. The thing beeped continuously although when tested to see if the siren would be set off (window open wave arms inside and bang seats) the siren activated as it should. But when the car was reset, the thing beeped even when in use and even when locked up ...


The initial drain, was as you say, down to a failed battery in the siren itself. The 20 - 25mA drain was going into trying to charge the dead battery, The charging current is limited to around that figure, to prevent damage to a good battery. The constant beep is an indication that the battery voltage has dropped too far for the unit to function. The beep will continue, until the battery dies completely. The current drain will continue though, and the battery will overheat, leak, and damage the pcb, making battery replacement impractical.
A diagnostic scan would have shown a comms error to the siren.

When the new siren was fitted, you had the warning beep, and comms error, so the battery was flat. The current drain would have been as before, as the battery was on charge. (If the battery was charged fully, the current drain via the siren would drop to almost zero).

Later, you activated the alarm, and the siren worked, so, despite the constant beep, the battery was charged just enough for the unit to function, as without working comms, (that error would have cleared), the siren would not sound.

It may be, that if left longer, the battery in the new siren would have charged fully, and the constant beep would have stopped. This would depend on how old the battery (and the new siren) was.

I'd really recommend replacing the battery in your original unit, and refitting it. Any alarm is surely better than no alarm?

The replacement battery mentioned on a similar thread recently, comes with wires attached, and once the old battery has been shipped off the pcb, the two wires can be soldered to the old battery tabs. I'm sure someone could help with that. You'd (well, the car anyway) be good for another 5 - 8 years.

Mac.


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## LesRSV (Jul 5, 2017)

Just to confuse things a bit more :roll: I would have thought the no comms error is down to the wiring or plug being dodgy as there is a separate code for siren battery low voltage, but the module (siren) can still be reached. I could be wrong of course. [smiley=help.gif]


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## PlasticMac (Apr 25, 2017)

LesRSV said:


> Just to confuse things a bit more :roll: I would have thought the no comms error is down to the wiring or plug being dodgy as there is a separate code for siren battery low voltage, but the module (siren) can still be reached. I could be wrong of course. [smiley=help.gif]


... but, it cleared between fitting the new siren, and triggering the alarm and siren, with no wire wiggling (I'm assuming you need comms to trigger the siren...). I didn't know there was a low voltage error code though.
Maybe beep = low voltage, and no beep = no comms? 
Mac.


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## silverbug (Jan 1, 2020)

LesRSV said:


> Just to confuse things a bit more :roll: I would have thought the no comms error is down to the wiring or plug being dodgy as there is a separate code for siren battery low voltage, but the module (siren) can still be reached. I could be wrong of course. [smiley=help.gif]


I think you are correct.
The only error code my car currently has is the siren battery low voltage one , I can clear it but it comes back instantly.
I have one of those new batteries which I'm going to try and install in the hope of curing it permanently.


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## PlasticMac (Apr 25, 2017)

Hi Silverbug, apart from the error "low voltage" the siren works (when alarm triggered, or beep on lock), and you have no constant warning beep?
If so, wonder if you could measure the battery voltage, when you open the siren up, both plugged into the car, and unplugged?
It would help us understand the unit a bit better.
Good luck. 
Mac.


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## silverbug (Jan 1, 2020)

PlasticMac said:


> Hi Silverbug, apart from the error "low voltage" the siren works (when alarm triggered, or beep on lock), and you have no constant warning beep?
> If so, wonder if you could measure the battery voltage, when you open the siren up, both plugged into the car, and unplugged?
> It would help us understand the unit a bit better.
> Good luck.
> Mac.


That's correct , it was a secondhand siren and I only repaired the system because I wanted to have the horn beep confirmation on locking, the siren is too feeble to work as a burglar alarm although it does work perfectly when alarm is activated and it doesn't beep unnecessarily when the car is at rest or locked & alarmed.
When I scan the car with VCDS the only fault code I get is one mentioning low voltage at the alarm siren (thought I'd taken a pic of the code but I haven't ) so I've been aware for a while now that the internal batteries must be failing slowly.
As long as it beeps each time that I lock the car I figured that it's working as intended which would buy me a bit more time .
Now that I have a new battery pack , I will have a go at replacing it before too long , I'll try and measure the voltage as requested.
Electrics are not my forté though so am not sure how well I will do :lol: .


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## PlasticMac (Apr 25, 2017)

I reckon that if you snip the battery leads about 5mm above the pcb, you can wrap the new battery wires around the pin, then just get the iron hot, apply solder to the iron's tip, to wet it, then iron to joint, feed a bit of solder into where they meet, a few seconds, solder will flow, and you're done.
Otherwise, put it in a box, and I'll do it.
Mac.


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## silverbug (Jan 1, 2020)

PlasticMac said:


> I reckon that if you snip the battery leads about 5mm above the pcb, you can wrap the new battery wires around the pin, then just get the iron hot, apply solder to the iron's tip, to wet it, then iron to joint, feed a bit of solder into where they meet, a few seconds, solder will flow, and you're done.
> Otherwise, put it in a box, and I'll do it.
> Mac.


Thanks, I think that's within my capabilities, am just a bit apprehensive about taking a Dremel to a working siren :lol: .
As long as the PCB isn't corroded hopefully it'll repair OK.
Cheers 
I'll update here when it's done .


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## PlasticMac (Apr 25, 2017)

silverbug said:


> PlasticMac said:
> 
> 
> > I reckon that if you snip the battery leads about 5mm above the pcb, you can wrap the new battery wires around the pin, then just get the iron hot, apply solder to the iron's tip, to wet it, then iron to joint, feed a bit of solder into where they meet, a few seconds, solder will flow, and you're done.
> ...


I used a junior hacksaw to split mine. Held it in a vice, worked around till I broke through, then finished with a Stanley knife. There's nothing too close to the join.
Mac.


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## silverbug (Jan 1, 2020)

Thanks for the tips , good to know  .


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## Mr Grinch (Mar 20, 2021)

So the fact that a couple of members had beeps on change over and it stopped after 24 hours, you guys think its a wire problem rather than the battery being charged ?


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## PlasticMac (Apr 25, 2017)

Mr Grinch said:


> So the fact that a couple of members had beeps on change over and it stopped after 24 hours, you guys think its a wire problem rather than the battery being charged ?


If it's charging, and communicating (which it was with the new siren), then the wire/connector is OK, imo.
Duff battery in your original unit.
Mac.


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## Mr Grinch (Mar 20, 2021)

Im talking about the new unit. I know the old one was dead. The beep was with the new unit with comm error when hooked up. So is the new unit battery knackered or was the beep because it was charging ?


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## davebowk (Aug 16, 2019)

Could be either, could have been sat on a shelf for 10 year


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## PlasticMac (Apr 25, 2017)

I think it was charging. Depending on the manufacturing date, it may have been fine, just flat battery (very recent date), or knackered battery, may work for a while (old date).
The manufacture date is all important, because the battery chemistry doesn't like being connected to a load (the circuit) uncharged long term.
If you can fit a new battery to an "old" unit, I reckon you have a very good chance of 8 - 10 years of use. 
Mac.


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## LongsanTT (Jul 27, 2021)

PlasticMac said:


> I think it was charging. Depending on the manufacturing date, it may have been fine, just flat battery (very recent date), or knackered battery, may work for a while (old date).
> The manufacture date is all important, because the battery chemistry doesn't like being connected to a load (the circuit) uncharged long term.
> If you can fit a new battery to an "old" unit, I reckon you have a very good chance of 8 - 10 years of use.
> Mac.


Been reading this and now a bit paranoid that my alarm battery is maybe 'on it's last legs'. Can anyone tell me what the alarm sound should be like if working correctly? Is it a beep or a proper horn siren?
I have done a test, locking with fob then unlocking with key and opening the door and i just get a beeping like a smoke alarm once a second for 30sec then repeats till i press the fob.
Mick


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## davebowk (Aug 16, 2019)

Yeah thats all they do, bit of a waste of time really


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## David C (Apr 15, 2013)

Mine is loud enough to hear inside my house.

It is the later "A" version though, so don't know if that is louder than the original square version.

It is also possible that the loudness can be changed. I've not looked into it, but I know my old Alfa 156 you could change it via country settings and there was one country that was noticeably louder.


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## LongsanTT (Jul 27, 2021)

Thanks guys,
But to be clear should it be a loud beeping (smokealarm?) or a siren (police car, air raid?)
No problem to change the batteries,but rather spend the time doing other stuff
Mick


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## David C (Apr 15, 2013)

Don’t think changing the internal alarm batteries will change the sound or volume.
They are just a backup incase anyone cuts the main car battery supply.


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## LongsanTT (Jul 27, 2021)

I'm not looking for any improvement, i don't know what normal should be. I've read about alarm batteries corroding and causing damage which would maybe make the siren fail. 
WHAT is normal sound from a correctly functioning siren? as original question. 
Ps. I don't get any audible sound when locking using the key fob
Mick


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## davebowk (Aug 16, 2019)

It's just a beeping sound, you can set it to beep once on locking with VCDS (and the free version will do it)


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## PlasticMac (Apr 25, 2017)

techfreak said:


> german ebay, theres a guy who's got a buy it now for £26.00 pounds odd + 13.90 euro shipping...so thats about there or there abouts...also trying some parts places/breakers


Give fixing it a go, nothing to loose. An ex breaker will soon fail, if it works. 
Mac.


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## LongsanTT (Jul 27, 2021)

davebowk said:


> It's just a beeping sound, you can set it to beep once on locking with VCDS (and the free version will do it)


Great, that's all i was looking for, so mine is fine at the moment. Not had it long and doing big refurb so checking everything.
Cheers


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## Telbert (May 13, 2021)

Is it not possible to fit an aftermarket alarm system? Mine works (now disconnected) but was going off due to a faulty door switch. Although the car is parked outside my living room window, I couldn't hear that it was activated unless I went outside. I don't want to go back to single glazed windows! Mostly knew it was going off when seeing the indicators flashing when I made a cuppa. At least it didn't disturb the neighbours. 🤣


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