Parasitic Drain BUT not found using normal methods

[sheffieldyorky]

Hi Guys & Gals
I say "Parasitic Drain" because i can't think of any other terminology to describe the problem
I am now on my second new battery, both are correct for the vehicle i.e. 77Ah
If the vehicle is left for two days it will fail to start.
I have tried all of the Forums that I belong to including this one and nobody has come up with an alternative solution, i.e. a wire from the negative terminal post and another wire to the negative lead both to finish at my multimeter set to mA's and i have going through all the fuses.
I have also searched on YouTube
I have even left the vehicle for two hours for it to go to sleep
There is no light in the glove box i.e. I have taken the festoon bulb out the same with the interior light.
When I start the car the ignition light goes out immediately
When I leave the vehicle the ONLY thing that is illuminated is the triangle for the hazard warning lights.
Has anybody had this or similar where all the fuses where normal but still losing a charge after two days
My vehicle is a A3 1.9Tdi 3 door hatchback P1 2009

[dudleybloke]

Any aftermarket alarm or immobiliser fitted?

[sheffieldyorky]

Hi there
Many thanks for the contribution to my thread.
In answer to your question the answer is NO to both
Thanks

[shtu]

Nothing specific to add, but have a look at South Main Auto on Youtube, he has a few excellent demonstrations of finding parasitic drains. He's also entertaining viewing generally.

[DarkMatter]

dudleybloke said:

Any aftermarket alarm or immobiliser fitted?

Or possibly a tracker that’s been there from before you bought the car?

[51mes]

The alarm doesn't have to be aftermarket:

https://www.ttforum.co.uk/threads/knackered-alarm-...

I've had the siren battery go on an old car of mine and it would flatten the battery much as in the above situation (mine was not a TT) - the only indication anything was wrong was the number of beeps the alarm would give on locking the car.

The other battery flattening situation I had was a stereo wired such that the switched supply was fed continuously rather than the continuous supply.

[Dark Star]

Have you checked the Body Control Module?
A bad one will cause the battery drain.

[ninjag]

Have you tried a code reader to see if there are any Audi specific codes coming up? Maybe a sporadically failing module is causing it.

[sheffieldyorky]

shtu said:

Nothing specific to add, but have a look at South Main Auto on Youtube, he has a few excellent demonstrations of finding parasitic drains. He's also entertaining viewing generally.

Hi there
Many thanks for your contribution to my thread.
I took your advice and watched "Battery Dies Everyday: Testing For Parasitic Draw" all 26.16 of it and it address's what I already know.
I am now moving on to the next reply.
Thanks once again
Tony

[sheffieldyorky]

DarkMatter said:

Or possibly a tracker that’s been there from before you bought the car?

Hi there
Many thanks for the contribution to my thread.
In answer to your question the answer I have searched all parts of the vehicle for anything that might be connected I did whilst installing my dash cam front and rear but it is not connected as yet, besides when I connect it I will be using a "hard wire kit" so there will not be any drain while the engine is off.
The only thing that I have connected is a cd changer BUT I used the existing supplied VW-Audi harness plug.
Thanks
Tony

[sheffieldyorky]

Dark Star said:

Have you checked the Body Control Module?
A bad one will cause the battery drain.

Hi there
Many thanks for the contribution to my thread.
In answer to your question the answer is "no"
Two reasons
1) Every item on the car works without a problem
2) When I undertook my test i.e. negative lead in series with my multi-meter etc. ALL the readings where either 0.01 OR 0.00 all these were in mA's
Thanks
Tony

[fbwinston]

It's not unknown for alternators to fail intermittently and short out, causing rapid discharge.

[magpie215]

fbwinston said:

It's not unknown for alternators to fail intermittently and short out, causing rapid discharge.

Just about to post the very same iirc its a diode that fails allowing it to drain the battery

[sheffieldyorky]

51mes said:

The alarm doesn't have to be aftermarket:

https://www.ttforum.co.uk/threads/knackered-alarm-...

I've had the siren battery go on an old car of mine and it would flatten the battery much as in the above situation (mine was not a TT) - the only indication anything was wrong was the number of beeps the alarm would give on locking the car.

The other battery flattening situation I had was a stereo wired such that the switched supply was fed continuously rather than the continuous supply.

Hi there
Many thanks for the contribution to my thread.
In answer to your question this is very interesting.
I will tell you why.
I live in a very quiet suburb, in as much if there is a strange vehicle parked on the street for any length of time then the curtains start twitching I'm sure you know what I mean.
Since I purchased the car in January 2020 I have never heard the alarm well it is a quiet street etc. etc.
So the questions are as follows
1) Where is the location for the unit ?
2) Where is the location for the sounder / siren ?
3) How can I test the alarm ?

BUT what puzzles me IF this is connected into the electrical system somehow why wouldn't I see a drain above 0.01 mA's
>
So can anybody tell me the location of unit & the siren /sounder on an A3 1.9Tdi 2009 8P1

[Tye Green]

sheffieldyorky said:

Dark Star said:

Have you checked the Body Control Module?
A bad one will cause the battery drain.

Hi there
Many thanks for the contribution to my thread.
In answer to your question the answer is "no"
Two reasons
1) Every item on the car works without a problem
2) When I undertook my test i.e. negative lead in series with my multi-meter etc. ALL the readings where either 0.01 OR 0.00 all these were in mA's
Thanks
Tony

are you sure you mean mA rather than AMPS?

even the lowest consumption of any device on the car (maybe an alarm) etc in good working order would draw more than 0.00mA.

also, if you have the multimeter range set to read mA, how did you change from "engine running with negative lead to battery" to "engine OFF with negative lead to battery VIA MULTIMETER" ?

a more detailed explanation of how and when you are measuring current is required

[sheffieldyorky]

ninjag said:

Have you tried a code reader to see if there are any Audi specific codes coming up? Maybe a sporadically failing module is causing it.

Hi there
Many thanks for the contribution to my thread.
In answer to your question the answer is NO
I have a Maxiecu dongle as seen
This woks via Bluetooth to my tower
Depending on the answer received will be my next task.
Thanks
Tony

[sheffieldyorky]

fbwinston said:

It's not unknown for alternators to fail intermittently and short out, causing rapid discharge.

Hi there
Many thanks for the contribution to my thread.
In answer to your question funny you should say that because I have purchased a new "Alternator Voltage Regulator for my Audi".
I have also seriously considered purchasing a slip ring for the alternator as well.
BUT I am not going to swap these parts because the ignition light always goes out.
Does anybody know what the following various readings should be ;
1) Engine running normal tick over
2) Engine running @2,000 rpm
3) Engine running under load i.e. head lights on & main beam and heated rear screen and stereo play just for good measure.
4) Reading taken from the positive post on the alternator, on items 1,2 & 3
5) Reading taken from the positive & negative post's on the battery 1,2 & 3.

I have a digital multi-meter, a digital clamp meter.

Thanks
Tony

[sheffieldyorky]

Tye Green said:

are you sure you mean mA rather than AMPS?

even the lowest consumption of any device on the car (maybe an alarm) etc in good working order would draw more than 0.00mA.

also, if you have the multimeter range set to read mA, how did you change from "engine running with negative lead to battery" to "engine OFF with negative lead to battery VIA MULTIMETER" ?

a more detailed explanation of how and when you are measuring current is required

Hi there
Many thanks for the contribution to my thread.
In answer to your question yes I do mean mA's and as said previously the mA readings were 0.01 & 0.00
If I had anything above that I would tracked it down and removed and or replaced the item.
See my reply about the alarm etc.
Sorry I may be a bit dumb here but I really don't understand your quote of the following :-
>
also, if you have the multimeter range set to read mA, how did you change from "engine running with negative lead to battery" to "engine OFF with negative lead to battery VIA MULTIMETER" ?
>
I have checked my original start of the thread and it does not mention that had the car running with the negative lead off !
Please copy & past or quote where I have written that
I proof check every reply
Thanks
Tony

[sheffieldyorky]

I will be away from my computer as I am now going for my lunch BUT all replies will receive an answer

[paralla]

If you can’t find the drain you are not doing it correctly.