'00 A6 Alarm System odd behavior

Hi all,

Sometimes after I park the car in the garage the alarm horn will emit a low
sound like the alarm is going off even though the car is not locked.

It's noticeable only because the garage is a relatively quiet place. The
sound level is 1% of the normal alarm level. Loud enough to hear in the
house/garage, but not loud enough to hear when the car is parked outside in
the driveway.

If I lock the car, the sound stops and it starts again after I unlock the
car.

It occurs mostly when the car and the garage are warm say 80 degrees F or
more.

I've scanned using VAG-COM which turns up nothing.

By morning, the sound has stopped. It doesn't run the battery down.

The alarm does work at full volume when activated (i.e. 'unlock door with
alarm on' or 'dog barking in car with alarm on' or hit 'panic button').

Any ideas?

Thanks, Glenn

In message >
"Glenn Spence" > wrote:

> Sometimes after I park the car in the garage the alarm horn will emit
> a low sound like the alarm is going off even though the car is not
> locked.

Are you sure that what you're hearing isn't the fuel tank vent
'breathing'?

--
Peter Bell (Note Spamtrap - To reply, replace 'invalid' with 'bellfamily')

Hmm. Not sure.
How would I know the difference? Perhaps by taking the gas cap off when the
noise is occurring?

Glenn Spence

"Peter Bell" > wrote in message
...
> In message >
> "Glenn Spence" > wrote:
>
> > Sometimes after I park the car in the garage the alarm horn will emit
> > a low sound like the alarm is going off even though the car is not
> > locked.
>
> Are you sure that what you're hearing isn't the fuel tank vent
> 'breathing'?
>
> --
> Peter Bell (Note Spamtrap - To reply, replace 'invalid' with
'bellfamily')

On Thu, 29 Jul 2004 19:04:20 GMT, "Glenn Spence" >
wrote:

>"Peter Bell" > wrote in message
.. .
>> In message >
>> "Glenn Spence" > wrote:
>>
>> > Sometimes after I park the car in the garage the alarm horn will emit
>> > a low sound like the alarm is going off even though the car is not
>> > locked.
>>
>> Are you sure that what you're hearing isn't the fuel tank vent
>> 'breathing'?

>Hmm. Not sure.
>How would I know the difference? Perhaps by taking the gas cap off when the
>noise is occurring?

That'd be a good place to start - though that would leave one wondering why
the sound stops when you unlock the car...

It's supposed to warm up here in the next couple of days so I'll see if it
makes the noise and then try the lock-unlock sequence to be certain that
they are or are not related. Seems like they are but it has been a week or
so since the last event and memories being what they are... Would be a good
time to try the gas cap removal to see if that has an effect (engine off of
course).

"daytripper" > wrote in message
...
> On Thu, 29 Jul 2004 19:04:20 GMT, "Glenn Spence" >
> wrote:
>
> >"Peter Bell" > wrote in message
> .. .
> >> In message >
> >> "Glenn Spence" > wrote:
> >>
> >> > Sometimes after I park the car in the garage the alarm horn will emit
> >> > a low sound like the alarm is going off even though the car is not
> >> > locked.
> >>
> >> Are you sure that what you're hearing isn't the fuel tank vent
> >> 'breathing'?
>
> >Hmm. Not sure.
> >How would I know the difference? Perhaps by taking the gas cap off when
the
> >noise is occurring?
>
> That'd be a good place to start - though that would leave one wondering
why
> the sound stops when you unlock the car...

Follow-up:

Well, it's 94 degrees here and a couple of minutes after I pulled the car
into the garage and turned it off the car was making the noise. I tried the
lock/unlock sequence which had no effect. I then opened the gas cap and the
noise stopped! I can't figure out why I thought it was related to the alarm
system but.......

Thanks for the correct analysis.

Glenn

"Peter Bell" > wrote in message
...
> In message >
> "Glenn Spence" > wrote:
>
> > Sometimes after I park the car in the garage the alarm horn will emit
> > a low sound like the alarm is going off even though the car is not
> > locked.
>
> Are you sure that what you're hearing isn't the fuel tank vent
> 'breathing'?
>
> --
> Peter Bell (Note Spamtrap - To reply, replace 'invalid' with
'bellfamily')