Parasitic drain ongoing problem help needed please

[Sheffieldyorky]

Hi, there peeps,

I have an A3 1.9Tdi 3-door hatchback from March 2009 making it a 8P1.

>

As the title states I have had this drain for some time now and have been unable to find the source despite the usual testing methods, i.e. digital meter on the mA range with the leads in the correct orientation, any way to cut a long story, I took out all the under dashboard cover's, steering column, glovebox etc. in a search for an obvious short etc.

At this time I was disconnecting the positive lead from the battery and I manually locked the car.

At the same time as this was happening, I purchased a new Junsun multi-media entertainment system ( I was awaiting arrival from China) to replace my Audi Chorus which I took out, it then started raining due to various other circumstances including the weather I was not able to get back to the car.

Finally, I then started looking for any signs of a fault using my HEX-V2 dongle, there were several fault codes but NONE that related to what I was experiencing.

I don't know what made me do it but I checked the multiplug for the Audi Chorus (the radio is in the house) for any signs of a supply and I found it in the multiplug, at this stage, there was no key in the ignition and both doors were shut, while sat in the car I pressed the remote to lock the car and waited and waited and I still had a supply from the multiplug.

So after a bit of research etc. I found the fuses are located in the engine bay # 8 and 9 I proved this by removing them and checking the multiplug supply it has now gone, so reinstated said fuses now back to square one.

First thing if I go out to the car in the morning take off the positive lead and then tap the positive battery post I get a very small spark which tells me something is energized but take out the fuse and there is no spark, I forgot to mention the door and the bonnet catch have been put into the lock position and I have to wait about an hour to start this procedure (sorry cart before the horse).

 What is really puzzling me is why is the multiplug still live even when the car has gone to sleep etc.

[cliffcoggin]

Tony.

How large is this drain from the battery? A few dozen miiliamps is normal for the alarm system. If it is significantly larger look for non-standard pieces of electrical equipment such as satnavs, radios, dashcams etc. and ensure they have been connected to an ignition switched power supply. It is too easy to connect such devices to a permanently live supply.

[Stevey Y]

9 hours ago, Sheffieldyorky said:

Hi, there peeps,

I have an A3 1.9Tdi 3-door hatchback from March 2009 making it a 8P1.

>

As the title states I have had this drain for some time now and have been unable to find the source despite the usual testing methods, i.e. digital meter on the mA range with the leads in the correct orientation, any way to cut a long story, I took out all the under dashboard cover's, steering column, glovebox etc. in a search for an obvious short etc.

At this time I was disconnecting the positive lead from the battery and I manually locked the car.

At the same time as this was happening, I purchased a new Junsun multi-media entertainment system ( I was awaiting arrival from China) to replace my Audi Chorus which I took out, it then started raining due to various other circumstances including the weather I was not able to get back to the car.

Finally, I then started looking for any signs of a fault using my HEX-V2 dongle, there were several fault codes but NONE that related to what I was experiencing.

I don't know what made me do it but I checked the multiplug for the Audi Chorus (the radio is in the house) for any signs of a supply and I found it in the multiplug, at this stage, there was no key in the ignition and both doors were shut, while sat in the car I pressed the remote to lock the car and waited and waited and I still had a supply from the multiplug.

So after a bit of research etc. I found the fuses are located in the engine bay # 8 and 9 I proved this by removing them and checking the multiplug supply it has now gone, so reinstated said fuses now back to square one.

First thing if I go out to the car in the morning take off the positive lead and then tap the positive battery post I get a very small spark which tells me something is energized but take out the fuse and there is no spark, I forgot to mention the door and the bonnet catch have been put into the lock position and I have to wait about an hour to start this procedure (sorry cart before the horse).

 What is really puzzling me is why is the multiplug still live even when the car has gone to sleep etc.

Hi the multi plug for the head unit always has a supply normally about 2amps this maintains the memory functions within the unit otherwise when you power it up the settings need to be altered.

Steve.

[cliffcoggin]

22 minutes ago, Stevey Y said:

Hi the multi plug for the head unit always has a supply normally about 2amps this maintains the memory functions within the unit otherwise when you power it up the settings need to be altered.

Steve.

2 amps when switched off? Perhaps you mean 2 milliamps?

[Stevey Y]

1 minute ago, cliffcoggin said:

2 amps when switched off? Perhaps you mean 2 milliamps?

Hi sorry Cliff I stand corrected.

[Sheffieldyorky]

On 5/15/2024 at 6:05 PM, cliffcoggin said:

Tony.

How large is this drain from the battery? A few dozen miiliamps is normal for the alarm system. If it is significantly larger look for non-standard pieces of electrical equipment such as satnavs, radios, dashcams etc. and ensure they have been connected to an ignition switched power supply. It is too easy to connect such devices to a permanently live supply.

Hi there Cliff

At long last, I was able to get around to the car (stacked up with laptop repairs) and started to test.

First thing I latched the driver's door and did the same to the bonnet catch.

Waited about 30-40 minutes, and sleep time varies from Forum to Forum, so I took an average, some people say 2 hours some say 4 or 5 minutes, go figure.

I used the Red lead on my DVM on the 10a scale connected to the battery NEG post & the Black DVM lead to the Negative lead from the vehicle, as seen in the image.

What I found was 0.06mA see image, I removed the 50a fuse and it disappeared see image.

I have tried to find out what this 50a fuse is protecting but failed miserably.

Oh by the way my radio is not fitted.

So I look to you guys & gals to come up with a solution.

As a final note when I connected the Negative lead from the vehicle there was a slight crackle similar to what I get on re-attaching the positive lead from the vehicle.

 

[Magnet]

Hello Tony, 

I think you are getting your amps and milli-amps in a twist. 
If you genuinely have a ‘parasitic drain’ of 0.06mA, you don’t have a parasitic drain! 
Interpreting your meter reading:- your meter is reading 0.06 of an amp, which equals 60mA. 
Does a drain of 60mA point to an issue? No - there or there abouts normal in my book. 
If you have say a 60Ah capacity battery, and left the car unattended, it would theoretically take around 42 days to drain the battery. 
Apologies, but what I’m missing here is what are you considering is wrong, and what are the symptoms? 

[cliffcoggin]

Tony.

As Gareth pointed out, what you wrote and what you show are not the same. Your meter shows 60 mA drain which is perfectly normal.

To mind there is no problem, so a solution is not required.

[Sheffieldyorky]

On 5/15/2024 at 6:05 PM, cliffcoggin said:

 

Hi there Clifford  & Gareth

Many thanks for contributing to my thread.

I think that the best solution is for me to show you the battery etc.

12v 72Ah 650CCA

I have also located the website

The battery website

I will now let you ask questions and I will do my best to answer them.

 

Edited May 18 by Sheffieldyorky

[cliffcoggin]

Tony.

What's the point of showing us pictures of a battery? I'm sure we all know what batteries look like.

The only thing I ask is what you perceive to be a problem with your car? It has already been explained that you do not have any excessive drain on the battery, so why do you continue this topic? Is there something else that either you have not explained or we have missed in your introduction?

[Magnet]

Hello Tony,

Saying it as I see it, I don’t have any interest in the battery at the moment - and certainly no intention of clicking on the link - other than to say it looks like a spurious brand to me. 
What I am interested in, and I’m not sure why you aren’t telling us! :- what symptoms is the car is suffering from? 
 

Typed while Cliff was responding. Sorry Cliff, I’ll leave this one to you to try to get to the bottom of. Bit odd? 

[Sheffieldyorky]

12 minutes ago, cliffcoggin said:

Tony.

What's the point of showing us pictures of a battery? I'm sure we all know what batteries look like.

The only thing I ask is what you perceive to be a problem with your car? It has already been explained that you do not have any excessive drain on the battery, so why do you continue this topic? Is there something else that either you have not explained or we have missed in your introduction?

Sorry Cliff

The problem with the car is that it is left not used for 5 - 6 days If fails to start OR is very sluggish and refuses to start.

I have not had my Audi Chorus plugged in since then.

Previously I was disconnecting the positive lead and then in the morning I would reconnect it and get a slight crackle between the positive lead and the battery.

If I know that I am not going to be using the car for a while, i.e. early February I went to Turkey for surgery so I knew I would be away for a while, so it was disconnected, I came home and reconnected the battery obviously started fine.

[cliffcoggin]

1 hour ago, Sheffieldyorky said:

The problem with the car is that it is left not used for 5 - 6 days If fails to start OR is very sluggish and refuses to start.

 

Thank you Tony. At last we have a symptom!

The battery is clapped out and needs to be renewed.

[cliffcoggin]

PS. Don't forget to have the new battery coded to the car or it won't work, and do please let us know the outcome.

[Magnet]

Hello Tony,

With any persisting electrical issue, it’s always worth getting the battery efficiency measured to establish whether it’s a contributory cause or not. 
Perhaps you could let us know whether you acquired the car with that battery, or if you bought it during your (how long?) ownership. 
Way forward:- take the car to an Halfords store and ask them to check the battery’s efficiency for you. Get the alternator output checked at the same time. 
If the battery is found to be sub standard, you may want to come back to us, before you buy a replacement from Halfords. 
My take on it, for what it’s worth:- It wouldn’t surprise me that the battery you have is ‘reconditioned reject’ bought because it was cheap. 
Please come back with the outcome - as Cliff says. 
 

[Sheffieldyorky]

5 hours ago, Magnet said:

Hello Tony,

With any persisting electrical issue, it’s always worth getting the battery efficiency measured to establish whether it’s a contributory cause or not. 
Perhaps you could let us know whether you acquired the car with that battery, or if you bought it during your (how long?) ownership. 
Way forward:- take the car to an Halfords store and ask them to check the battery’s efficiency for you. Get the alternator output checked at the same time. 
If the battery is found to be sub standard, you may want to come back to us, before you buy a replacement from Halfords. 
My take on it, for what it’s worth:- It wouldn’t surprise me that the battery you have is ‘reconditioned reject’ bought because it was cheap. 
Please come back with the outcome - as Cliff says. 
 

Right I am going try and write this again, the first session disappeared when I tried to “copy and paste” some text, so this time I writing it all in a word document.

What I previously wrote was something like this.

My vehicle was purchased 16^th January 2020

I think it only fair I give you a full rundown of what I have done and had done to the car up to date, what will be missing are the dates, sorry.

These are not in any order but just as I remembered them

New battery (1)

New driver’s door lock

Bonnet resprayed ( I know it has nothing to do with starting or electrical problems )

Replaced the wiring harness driver’s door

New key and chip programmed at my home

Installed LED lighting all round (no capacitor’s needed)

Removed Audi Chorus

New clutch with “Dual mass flywheel”

New battery (2) which was returned due to buckled plates

New battery(3) purchased 15^th January 2024

The data for this battery is 72Ah 650CCA which is way more than advertised.

I had been removing the positive lead when new battery (2) was on the car, I don’t do it now, BUT I still get the crackle when I am  putting on either negative or positive lead.

As the text from Cliff, “PS. Don't forget to have the new battery coded to the car or it won't work,”

On the internet  [www.htsaves.com ] I find the following text

How Long Does it Take to Leave the Battery Disconnected to Reset the Car’s Computer?

To reset your car’s computer, you should disconnect the battery and allow time for the residual energy in the electrical circuits to dissipate completely. Typically, this process can take anywhere from 15 minutes to an hour. This ensures that all the stored electricity is cleared out of the system.

Old battery (2) off new battery (3) on changeover was minutes nowhere near 15 minutes, the battery ( 3) had already been charged up awaiting my arrival.

I have just had a thought with battery (2) it was left off overnight and sometimes more than a day But when I reconnected the battery I got the crackle but the engine would start and run without a problem.

With battery (3) I do not disconnect either lead, I’ll just jump in the car go to the roundabout and back total maybe 2 miles, pull it up onto the drive switch off and go inside.

I am now booked in @ Halfords for a “battery  efficiency” check 09:30 Monday morning.

I will appraise you of the results and I will upload any documentation should I get it.

Till tomorrow then

Tony

P.S I know that I have included certain items that are not electrical related

[Magnet]

Thanks Tony,

There’s an awful lot of information there that we don’t need, but….

You bought the latest battery because it was the cheapest you could get at the time-? 
Did you get it on-line or locally. 
It’s likely the battery should have been coded to the car, but not absolutely certain of that for your age car. Hopefully we will get some more experienced opinion on that.

If it does need coding, then failure to code it can ( I believe) lead to over- charging, since the car will treat it as if it’s still the old one. Over charging can result in toasting the battery. 
Pulling terminals off should be totally unnecessary and should not be done. 
Let us know how you get on Tony, and give us an answer as to why you bought the brand you have now. 
Good batteries are an investment.

[Sheffieldyorky]

On 5/19/2024 at 8:41 AM, Magnet said:

Good afternoon one & all

As promised I have been to Halfords and have attached their evidence.

The “Starter test” “Good battery”

He told me that the CCA was 12.4

13.87v no load

Then with a load ( rear screen, light’s main beam etc. fan ) 13.13v

And on the Halfords sheet at the bottom “Charging test, No problems”

His words were “I can’t understand what the problem is”

I purchased this battery locally on January this year.

I asked him about coding, his words “coding is mainly used for vehicle’s with stop start facility.”

I spent 30 minutes chatting about the test I also explained about the crackle on removing the positive, his words “I have no idea”

 

 

[cliffcoggin]

Tony.

The Halfords report is inadequate in that is performing a simple voltage test under a meagre load. What is needed is a deep discharge test which simulates the heavy load of about 200 amps imposed by the starter motor, rather than the dozen or so amps used by the lights and screen heater.

Halfords are also wrong in their comments about battery coding. To my certain knowledge A3s from at least 2007 need to have the battery coded in order for the car's electronics to work correctly. It is even possible, though I am less sure of this point, that your repeated disconnection of the battery is causing the coding to be lost. It would need somebody more knowledgable than me to clarify that.

Whatever the cause of the problem, the symptoms you presented of the battery being unable to hold a charge are classic properties of a faulty battery, hence my conclusion that you need a new one. I suggest you get the car tested by somebody more competant than the clowns at Halfords. If and when you get a new battery get a decent one, have it coded, and never disconnect it without good cause.

[Sheffieldyorky]

1 hour ago, cliffcoggin said:

Tony.

The Halfords report is inadequate in that is performing a simple voltage test under a meagre load. What is needed is a deep discharge test which simulates the heavy load of about 200 amps imposed by the starter motor, rather than the dozen or so amps used by the lights and screen heater.

Halfords are also wrong in their comments about battery coding. To my certain knowledge A3s from at least 2007 need to have the battery coded in order for the car's electronics to work correctly. It is even possible, though I am less sure of this point, that your repeated disconnection of the battery is causing the coding to be lost. It would need somebody more knowledgable than me to clarify that.

Whatever the cause of the problem, the symptoms you presented of the battery being unable to hold a charge are classic properties of a faulty battery, hence my conclusion that you need a new one. I suggest you get the car tested by somebody more competant than the clowns at Halfords. If and when you get a new battery get a decent one, have it coded, and never disconnect it without good cause.

On 5/19/2024 at 8:41 AM, Magnet said:

 

Hi Cliff

Please see this from another Forum VW Audi Forum

Thread title

Does 2011 A3 need battery coding?

31satara 
Hopefully a short one. A freind has a 2011 2l petrol A3. In Febuary his battery (original) was completely flat and he bought a new Bosch S4 (74Ah) which I fitted for him. Yesterday it wouldn't start or turn over. When I went to look today the battery was completly flat, 4V off-load. Being retired he doesn't use the car much - maybe once a week a few miles to the shops and back. Normally I would suspect that he's just not using it enough, but it seemed odd that the battery was so flat (unless he has left things on, but he says not). He then said he had been looking on the internet and some cars need new batteries coding - can anyone tell me if this model does need replacement battery coding? Thanks

31satara
I don't think it is the 2l, rather the 1.8tfsi

philipharmes 
It's usually only cars fitted with stop/start systems ( and therefore AGM or EFB batteries ) that need coding.

Fexo 
Yes, I fitted an S4 to my wife's old A4 Avant and no coding was needed. When the battery on my A3 with stop/start had to be replaced, that did need coding.

Hold on: my car is a late 2011 A3 2 litre TDI and has stop/start. Are you sure about the battery? The garage was going to fit a standard S4 on mine until they realised it had stop/start which requires a much more powerful (and expensive) one.

31satara
Thanks for the info. It doesn't have stop/start nor the multi-media display which seem to be pointers towards coding required. However, the owners manual that came with it states coding is needed when replacing the battery. I connected it to VCDS and was able to go through the coding proceedure without issue. Hopefully that will improve it a bit, but I'm still not convinced it will make much difference - I think he just needs to use it more (it's only got 35k on the clock). There must be loads of similar cars that have had replacement batteries fitted without being recoded.

Texmilb 
I have a 2011 2.0 TDI with stop/start and when my battery died 4 years ago I just fitted a replacement from Halfords and has been no problem ever since.

The spelling mistakes are not of my doing.

So I draw this conclusion, my A3 does not have a start facility, I will now leave the battery cables in situ and I will plug my Audi Chorus back in, the only thing that I will do is leave the bonnet unlatched, so if I say IF it fails to start then I will be able to jump-start it.

To be honest I can see that the alternator is charging the battery, but the first time that it fails to start then I will let you guys know, also I will update you as to how many days since the engine was running, so I will class this as 20th May DAY 1

[cliffcoggin]

Believe what you want Tony, but I can assure you that coding is a neccesity for things other than stop/start. The car's electronics are sensitive and require a stable power supply from a battery with no internal faults in order to function properly.

I wish you luck with your problem, but it seems I am wasting my time trying to convince you so I am withdrawing from this discussion.

[Stevey Y]

2 hours ago, cliffcoggin said:

Believe what you want Tony, but I can assure you that coding is a neccesity for things other than stop/start. The car's electronics are sensitive and require a stable power supply from a battery with no internal faults in order to function properly.

I wish you luck with your problem, but it seems I am wasting my time trying to convince you so I am withdrawing from this discussion.

Hi Cliff how long has this been under discussion and for the benefit of anyone who wants to know, since 2007 most of the major manufacturers installed some sort of battery energy monitor, Fords use a battery counter system as do Vauxhall, Audi and Mercedes use a monitor system which is attached to the earth lead, both systems need reseting when a new battery is installed this informs the ECU and the Alternator to learn new values about charging, what is painfully clear having studied the brand of this battery it comes from no definitive source, even the company website only mentions the batteries are developed by them and their partners who are their partners are is anyones guess, basically its a cheap range of European parts that are being flooded in from Europe a bit like the NAPA parts from America, from what I can gather EUROREPAR have been going for twenty years if you lodge that against Bosch and Yuasa who have well over a Hundred years between them you can see where your extra money goes, I have recently had to change the battery on my wife's Alfa which does about fifteen hundred miles a year the last Yuasa unit has lasted five years so I bought a new Yuasa which has a four year guarantee, so yes you are right the battery probably is defective.

Steve. 

[Magnet]

Many thanks Steve for clarifying this for the benefit of others. 

Hello Tony,

I’m not sure what you now want to believe, but you have a battery of dubious origins, and I believe until you replace it with a reputable branded one, and get it coded to the car, you stand little chance of getting anywhere with this, but it must be your choice. From my side, and apologies if this appears critical, but you seem to be bombarding us with unnecessary detail. 
Anyway, back to your battery and charging check:- 

A couple of observations - the charging voltage measured at 13.8v at best, is below par, and I would be expecting around 14.5 volts. 
I’m not sure what he told you about CCA measurements, but surely Cold Cranking Current would be measured in what it is - amps. not volts.

If you are going to decide on fitting a reputable branded battery, you won’t go far wrong with a correct-for-car Exide from Tayna Batteries. Give them your reg. no., and they will advise on the correct one.
You will need to further investigate the alternator output.