Lets talk battery chargers
 

My D3 does not get much use for weeks on end, and then I'll do a 400 mile return journey.

For example in the last 5 weeks my D3 has been used almost daily, yet it has covered just 55 miles.

As a result I think that the car is consuming more power than I am putting back in, that coupled with the slight battery drain issue is leading to less power.

After 5 weeks I am getting up in the morning to find that the BCM has turned a lot of stuff off, so keyless entry is disabled and the light in the door is not flashing so I need to use the unlock button on the key to open the car. Once inside I can start the car with the start button, and the battery monitor is down at 15% or so. After driving to work, its up at about 80%, but I switch off at that point. Same at the end of the day, except I usually leave the engine running for a bit to get the battery meter to 100%

We all know the battery meter is just measuring voltage, and I confirmed that with the meter on 100% the battery is still receiving current from the alternator, which once charged the BCM stops.

So looking for a charger really, not to expensive but something I could use say weekly to topup the battery. I've tried a big solar one directly on the battery but I don't think it was doing much as they tend to be to help maintain a well charged battery.

Battery is fine, its 20 months old and never been run fully flat and always starts the car without issue. The car will be fine for several weeks after the long run, before getting back to where I am now.

C-Tek chargers...

+1

CTEK MXS 5.0 can maintain 110Ah like ours.
Not much change from £60 notes though.

Check out this one available at Lidl from tomorrow. http://www.lidl.co.uk/en/our-offers-...&id=27134&ar=3

I have LCD version of the same charger https://www.youtube.com/watch?v=NO9MWevR1yk (not me in the video ) and it's been great to top up or keep charged battery but being 3.8A it takes long time to charge from flat. It takes probably around 20 hrs to go from 20% to 80%. At 80% it cuts current to 0.8A just like C-Tek chargers so it takes another 24 or so hours to get to 98% so you are looking at 2 days or more to go from flat to fully charged.

manny this could also be caused by a faulty BCM as that is exactly the behaviour exhibited when they start to go a bit funny. Suggest you plug vagcom in and recode the battery by adding 1 to the previous coding and digits and then the BCM thinks you have fitted a new battery and you don't seem to get the same issue again for ages if that's what it is. Worth a try anyway. +++

I am now more than sure the reason for the overnight battery issue is the boot electrics. Last night I needed to access the boot after driving home from work, and this morning the battery was fine and just under 100% charged on the meter. Same this evening, 100% charged after sitting in the car park all day.

So what on earth can cause issues with the boot electrics. I know that if I close it manually I can sometimes press down on the supposedly locked boot and here another click like something was not engaged properly. My electric boot is missing the little spring so it does not close itself without opening up again. I dont think its the boot light as that goes off after a short while if you leave the boot open anyway.

I've still decided to get a charger, and may go for the ctek one mentioned, at 11 years old she is developing electrical gremlins.

Well the car did it again, so I've followed Neil's advise and recoded the battery module by incrementing the serial number one.

Lets see what happens now.

At least next weekend I'll be doing 400 miles and putting plenty of charge back in.

My understanding is you need to fully charge the battery then recode the BCM or does it not matter?

Well coding the battery made no difference, after 24 hours battery back down at 15% and this is despite leaving the engine running outside for 1/2 hour and then going on a 15 minute drive as well. The tell tale sign is that the alarm light is no longer flashing in the door and the keyless is dead.

I've been all round the car and opened/closed everything that can be, that has been known to sort it before. it used to happen once in a blue moon, but its a bit of an issue these last two weeks.

I must have one heck of a current draw, but everything is working and nothing seems untoward. For now I've left the car on the level outside, with the parking brake off just in case I need to push it out of the way due to flat battery to get the tired old A6 out.

Try taking the battery off and charging it over night or as long as possible, once fully charged then try to recode the BCM, iirc it gets its new parameters from the new battery itself, either that or invest in a DC ammeter and let the car go to sleep with access to the fuses without disturbing anything and start pulling them till you find what circuit it's on.

That's not going to put much energy in battery. In the best case scenario if there is say 20A going in the battery with 90% efficiency 45 minutes it will only put 13.5Ah which will be 13.5% on the 100Ah battery.

To charge battery from totally flat you are looking at 10hrs with powerful 10A+ charger to get it to 80% or 20hrs with 5A charger. Last 20 % need to be charged at lower rate with 2A or less and most smart chargers limit current to 0.8A and efficiency is lower when battery gets fuller so to go from 80% to full will be another 25-30 hrs but you can leave it 80%, no need to get it to 100%

Battery might have suffered as well if it has run nearly empty several times or remained nearly empty for long periods of time.

Yes, I think you're right. Its been 6 weeks now since the car did any meaningful mileage, on Friday I am doing a 4 hour drive in the D3 and even that may not be enough, and the following weekend I am driving from Stevenage to Boston, Lincs and from Lincolnshire back to Dorset.

I'll stick VCDS on it when I get to work, assuming it starts as its been sat all night with the battery low, I did check yesterday and according to the BCM the charging current was around 10A and alternator output was 15V.

I have always had a battery drain problem anyway, where from fully charged it would go down to 15% if left for a week without being touched possibly due to faulty keyless door handles which show an intermittent fault.

I'll try and get a charger today, but being in a rural town options are limited, the local Homebase has one but thats about all I can get locally today. I really want to get the battery into a good state ASAP so what about this one.

http://www.homebase.co.uk/en/homebas...charger-141975

This is a scan from the car this morning, after I reset the codes yesterday morning.

Car started fine this morning, keyless entry was dead as was the alarm. The door light had stopped flashing by 10PM last night. Battery meter had 2 bars showing

This morning I checked the measuring blocks, and when the engine is switched off and everything else off but the car still "Awake" it was taking 8A from the battery, so it obviously does this until it goes to sleep. At some point I'll need to check the sleep current.

Address 61: Battery Regul. Labels: 4E0-910-181.lbl
Control Module Part Number: 4E0 910 181 A HW: 4E0 915 181
Component and/or Version: ENERGIEMANAGER H02 0230
Software Coding:
Work Shop Code: WSC 00217 217 52026
Additional Info: 000915105AK von VA0 1308220489
Additional Info: Geraet 52026
VCID: 1E37DA4BB027
4 Faults Found:

02273 - Quiescent Current Stage 2
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 7
Fault Frequency: 2
Mileage: 235641 km
Time Indication: 0
Date: 2015.10.04
Time: 12:36:55

02276 - Quiescent Current Stage 5
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 7
Fault Frequency: 2
Mileage: 235641 km
Time Indication: 0
Date: 2015.10.04
Time: 12:37:05

02274 - Quiescent Current Stage 3
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 7
Fault Frequency: 2
Mileage: 235641 km
Time Indication: 0
Date: 2015.10.04
Time: 12:37:15

02277 - Quiescent Current Stage 6
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 7
Fault Frequency: 2
Mileage: 235641 km
Time Indication: 0
Date: 2015.10.04
Time: 12:37:25

Here is mine, hope this helps.

Address 61: Battery Regul. Labels: 4E0-910-181.lbl
Part No SW: 4E0 910 181 HW: 4E0 915 181
Component: ENERGIEMANAGER H02 0160
Revision: 00000000 Serial number: 00000000010676
Shop #: WSC 00000 000 00000
VCID: 5DB1B54184D4E3D61D-8008

Subsystem 1 - Part No: 000 915 105 AK
Component: von VA0 301008802E
Coding: 303030393135313035414B56413033303130303838303245
Shop #: WSC 73430 210 01865

No fault code found.

It's better than nothing but I would not be prepared to pay £50 for it. It's older design transformer type so bigger, heavier, less efficient and not fully automatic like new SMPS smart chargers. On the plus side it has fairly high current at 8A so will charge battery quicker but I would not leave it unattended to the battery for long periods of time as it may be charging battery with too much current when it gets near full state and causing it to loose water.

You can do a search on ebay by putting in your postcode and selecting distance, you might find one nearby. Or if you have Lidl not far away you can check if they still have the one I linked before, it's excellent value for £13.99 but will be a bit slow at 3.8A

That's a lot of current with everything off.

It takes between 20-30 minutes for the system to 'go to sleep' after everything is switched off. Opening a door awakens the system again, turning on certain switches awakens the system again, opening the boot awakens the system again if you see where I'm coming from. If you require the door to be open to check the drainage then you need to open it and leave it open for half an hour before checking... Hope this helps

I've just popped into Lidl next to the Halfords I intended to visit some 25mins from work, so I've got the one linked to earlier in the thread. Its a 4.8A charger, but its intelligent unlike the RAC one. So as another plus the car had a 1 hour run, so lets see how long that lasts.

Poor car is currently sitting outside with no power and the battery is hooked up to the Lidl charger in situ but with the cables disconnected.

Could not work out how to lock the drivers door with no power, and there is a mains cable protected by RCD running into the boot where the charger is located. its raining but the socket and charger are right in the back of the boot and the boot itself is closed as much as I can.

The weather forecast overnight is not good, so just before going to bed I'll disconnect the charger and give the car some well earned power so I can lock it and I don't fancy leaving the power lead through an open kitchen window either.

So it would have had 6 hours on the charger this evening, in addition to the longish run earlier.

I also discovered earlier, you can connect to the BCM with VCDS even with the ignition fully off.

Put the battery back onto the car lock all the doors then open just the boot with the fob, disconnect the battery again then get the battery charger on something solid like a piece of wood or a molded plastic tool box put the extension lead in the boot as well, hold the cable at the join between the rear lights, it should fully close then and be water tight, that's how I did mine when it was parked up for near 3 months and had to keep the battery charged +++

Ps, extension leads will differ in diameter so don't slam it **** but if it's just a DIY extension then it should go gently, opening the boot you will have to do by the lock in the trim above the number plate light, it can be stiff but it should unlock the boot without power :)

PPS sorry didn't read the kitchen window bit, but some windows have the slightly ajar latch that still keeps the window closed but with an air gap and probably enough to leave the cable coming through.

I disconnected the charger at 11.30pm, and reconnected the battery. After setting the clock and one touch windows all is good. Left the car until 9am this morning and nothing powered down overnight.

I'll see what the weather is like later and perhaps hook the car up again in trickle charge mode directly on the battery post (-) and battery(+) and leaving the car connected to the battery,

I found the BCM messes with the charging of the battery and the only way to fully charge the battery is to disconnect from the car and charge on its own, I left it connected to the car and on charge for 3 days and it still hadn't fully charged, it took 18ish hours iirc to charge fully when disconnected from the car with my 6A RING charger, I was leaving it plugged in and it was still reading low on the battery meter on MMI before hand.

Not sure whats going on now.

Checked battery with a DMM last night at 9.30pm, reading 12.6V with the car connected and awake. Went to go to work this morning and back to square one, battery meter on 15% and all convenience functions disabled.

Either the battery is ***** or I have suddenly developed a worrying persistent current drain. Thing is once the car is in this state the battery stops discharging.

I sat in the car yesterday early yesterday evening and watched the BCM with VCDS as the car went to sleep. After switching off ignition car was drawing 7 amps, which over the next 15 mins dropped to 4.5amps and then lots of relays clicked and the car went to sleep. Sadly VCDS also lost connection to the BCM at exactly the same time.

Tomorrow lunchtime I'll visit the place where I purchased the battery and get them to test it and see what it reveals.

Right, I've just got back home and stuck the DMM across the battery, it was reading 12.54 volts after driving the mile back from work. Battery indicator was again at about 15% when leaving.

I've attached a VCDS scan of the car as it was tonight, but I had not cleared the codes since disconnecting the battery. Some of the listed faults were clearly present before I did that anyway.

I've also attached a measuring block log of controller 61, the engine and everything else was off but the car still awake. Column 3 shows the current draw recorded by the BCM of 8 Amps.

Something I am wondering, although the alarm siren is not reporting any faults is, can it be causing an issue since the alarm is one of the last things to be shut down by the BCM as the main battery discharges and once the battery gets to a certain point it stops discharging. I have read of drain issues caused by the siren on here, so as long as its not raining tomorrow I might get time to access the siren and disconnect the wiring.

When I got the car the siren was dead, so I got a used from A8parts. That one also failed 3 months later, so the one currently fitted has been in the car for 18 months but was also secondhand from a8parts when it was installed.

I still have the two older ones, and I know the car is not happy with it just disconnected so if the current draw drops after pulling the connector I could refit one of the other dead ones perhaps?

If you need any current draw values from my D3 for comparison let me know +++

Hope you manage to fix this problem without too much further grief.

Something to compare against would be handy.

With VCDS connect to controller 61 and look at the measuring blocks one of them (channel 2 I think) has current flow in amps. With the engine running it reports a positive value since you are putting charge back into the battery. Switch off the engine and press/hold stop on the keyless until the steering lock engages, wait until the interior lights go out and that is where I get the 8 amps from (A negative number since I am now taking power from the battery)

My car has AMI and the full phone kit and TV which appear to be powered until the car goes to sleep, but a rough idea would help.

My car goes to sleep after 15mins but I loose the BCM through VCDS because the CAN gateway goes to sleep as well.

I don't have phone or bluetooth, shouldn't matter too much. Leave that with me and I'll get my values to compare. If you don't mind waiting 36 hours as I'll do it Friday +++

8 amps with everything off even if it's not completely off but in standby seems a lot. What about that fan control module you mention in another post? I think it's getting power as you can have residual heater on with car switched off and locked. Since you are having problems with it may it's draining your battery. Try pulling the fuse for the fan and see if current draw reduces.

I pulled the alarm siren this evening, there was a drop in current draw on the BCM from 8.2 to 7.9 amps with everything off and the car awake. Question is supposing those 300ma are the siren batteries charging how long would it take for the BCM to shut everything off if that 300ma drop does not stop. Poole Audi have quoted £139inc. VAT for a brand new alarm siren, they sent me the ETKA screen shot. Question is do I spend that on something that may or may not fix it.

Although I have issues with the heater blower controller, I have the solar sunroof, so when you switch off the ignition the supply switches to be powered by the solar panels on the roof. That switch does happen because when the sun is out you can hear the heater blower running, and in the dark all is silent.

I've used the car a number of times today, first thing to drive to work and it was the usual 15% and keyless entry off. Same again at lunch time and this evening. Everytime its always started well without any hesitation.

I am doing a long drive this weekend, so will keep an eye on it.

Have you tried putting the car in transport mode?

No, not tried that. However all was fine this morning, got in the car using keyless entry and started the car, checked battery meter and its on 100% despite being parked for 13hours, its not done that overnight at all this week. Who knows what\s going on.

Tested mine with VCDS. In the same state (everything off) mine was drawing 7.2A. However, before it went totally to sleep, it drew 8.2A for about a minute twice.

What is your Qv value? It's in block 3. My old battery was showing as 55Ah. My new battery is 0Ah.

Update time.

I did the long drive Friday night, engine was running for about 3.5 hours and I got to Hertfordshire at 9.30pm. Car was fine the following morning when I drove from Stevenage to Watford and back again, then did a run to the council dump Saturday evening.

The car has been parked up since 5.30pm Saturday, and this evening the battery has returned to the same low state and the door LEDs are currently not flashing.

Debating wether to put the charger on it again for a few hours, that will be all it gets here as the car is right by a main road.

Well I decided to stick the charger on it for as long as I can this evening, measured the voltage with a DMM and it was sitting at 12.26V.

Car started fine as I needed to to reverse it onto the driveway, there she sits now with an umbilical cord (life support almost) on the charger without power again.

Any way to test how damaged the battery now is after 3 weeks of being run this low, I guess a visit to the local Halfords to determine the battery state maybe in order unless I can find someone locally to Stevenage who can be trusted.

I am wondering this is something thats just been building up as she has always had an unidentified drain issue. When the battery was new it would go from 100% on the meter to 40% in about 5 days, however because the car is used daily its never really been an issue.

Manny have you ever replaced the Battery Management module? They can fail often with similar results to what you seem to be experiencing ?

Nope, not replaced that Neil, still the cars original one from what I can tell based on its very early firmware version.

Have you read the Qv (battery ageing) value yet?

I'll do that this morning,

Despite being on the charger until 11pm last night at which point I reconnected the car, the battery was at 11.7V this morning. Car still started ok though, but I had to use the key in the ignition, and after a 1/2 hour drive this morning it was at 12.31V but with the DMM connected you can see the voltage dropping. Current battery is a 95ah Varta blue top and 20 months old, not the 110ah I though.

I think the battery is poorly in addition to whatever the draw is. I've emailed Hatfield Audi regarding the alarm siren and sourcing a new one. I've read on vwaudiforum a thread where the alarm siren was causing constant draw due to battery failure as it is always on regardless of the BCM

Sitting in car now, QV value is zero, alternator is throwing more than 20A at the battery.