ECU and battery Problems

[PsYcHe]

Gave mine a try the other day, and it ran the MMI for quite a while before doing the auto turn off, so either the newer battery ECU, or the software update to 5570.

[limoncello]

looking good then, i can do without the cost of a new ecu, just had another baby

[limoncello]

had no trouble for last 2 weeks , been turning everything of and no issues,

Took it in to Audi, they said that indeed a software update would fix the problem.

2 hours later , it didnt fix the problem , so have had to leave the car in over the weekend with everything on to run the battery down and let them diagnose on monday.

[limoncello]

well got the car back today

they only thing they did was the software update, and diagnose each day to see if the battery had leaked, as thet believed the update woulnt have fixed it

this was based on the fact that the radio software was up to date

anyway they say the battery hasnt leaked after the update so may have fixed it

we will see, if its going to go again it will be within 2 weeks

[Architex_mA8tey]

Fingers crossed, its a real bitch to find solutions to issues like this

[Radman]

Sorry to hear you're still having problems. I have the same issues, battery drops to 10% when parked sometimes within minutes but apparently charges back to 80% on short run to work. I also have hybrid TV tuner (which works fine) I found a persistent voltage drop (35mV) across the 10A fuse to TVtuner circuit (third one down left hand side in the boot) even after car was parked and switched off for several hours and on this basis started pulling the fuse every time I parked and this has stopped the battery drain. Dave at A8 parts has been very helpful and we decided on MMI software upgrade to 5570 on the basis of the TSB which gave this as a solution to persistent drain from failure of this module to shut down. It seemed to work for a couple of nights but then recurred and battery was barely able to crank the starter. Downside of the upgrade was my bluetooth phone has disappeared!
I'm also suspicious the battery manager is not allowing a full charge of the battery when indicating the too rapid rise from the 10% level (we decided to switch the battery meter back on) and that the battery is chronically undercharged so I'm currently giving the battery a long session on the conditioner charger before looking at trying replacing the battery ECU. What do you mean when you say you manually switch off mmi and how do you know how long it is taking to shut down modules? I kind of feel I am getting closer to a solution but it is seriously frustrating as I have also suffered the broken gear tooth on the MMI display and am going to try the brass replacement repair.

[limoncello]

Theres a lot of people out there with the same or similar problem.

I shut the MMi down simply by a long press on the small volume knob, but before this i click on telephone > Setup > Switch off phone

Ive no idea how long the modules are really staying on, i was doing this "shutdown" procedure as a test to see if the TSB could be correct.

As I put a brand new battery in - and it took 2 weeks to run it down till the issue occured, i beleive thats the time im going to have to wait to see if it reoccurs or whether the 5570 actually fixed it.

from what ive been reading im not sure the TSB goes far enough, and its possible that not only the radio's failure to switch of is the problem, others have done various tests and discovered the nav or the telephone at fault (hence me switching of mine)

as architex says its a bitch to find solutions to strange issues like this

but if it reoccurs i think i may change the energie manager just to discount it

give yours a try, but first vagcom a new battery serial number, give it a run , then switch everything of, if you dont reset it first it that fault of a diminishing battery will always be there.

[snapdragon]

I too have had this recently.
My battery is only 6 months old VARTA and coded correctly.
Software is 5570.

I parked on the road and left the sidelights on for maybe 4 hours and when I returned the keyless entry had stopped working, a sign of a low battery.
When inside, I checked the meter and it said 10%.
The car started but judging by the dashlights flashing off it was a struggle.
By the time i got home 7 minutes later, it was on 60%.

The next day, it got up to 80% on the way to the shops and I left the blowers on for 45 mins and when we returned the battery was flat, so I called the green flag and they started it and said it was charging low at 12.6V.

When I got home ( a much longer journey than the night before) it said 30%. So I charged it from the mains. I also disconnected the battery and reconnected and now it charged at 13.40V.

It has been for 3 days since.

I think when the battery gets low, it scrambles or crashes some module, maybe the power manager or something and so disconnecting the battery resets everything. Then clear all the codes with VCDS.

[47p2]

What is this battery coding I keep reading?

[limoncello]

the battery meter is not a good indicator, it seems to be more battery condition than power, mine is draining without anything switched on, although only at a small constant amount. and often doesnt go up again, even on a 200 mile drive

I had 5570 too, but not every update had been done, the Audi tech who updated mine believed that the problem hadnt been resolved as my Radio was on the latest software, but i believe its not only the radio software at fault

once the fault occurs you defo need to update the battery serial with vagcom or the car beieves your battery is on its way out

touch wood the car has now been ok since the update on friday.