i would do if the car didnt keep saying "Start engine or will shut down in 3 minutes, and flashing battery symbol etc, it also stops the auto boot opening

Hmm... could be the power ECU on its way out then. has it been jump started at all?

no, no jumps

ok, now ive got the car back with apparently a good battery, i went in to the hidden menu and unticked the battery meter,

so far its working fine, for the first time in ages ive been able to keep the mmi open for more than 5 minutes without the engine running and without getting the 3 minute shutdown warning.

5 days gone, no problems at all, done quite a few short hops and used the boot quite a bit too, something that was garanteed to get the warning shutdown.

could it be that audi knew what they were doing when they turned the batt meter of in the MMI update, the only other change to the car is the new glow plugs.

after installing the headrests, playing and testing etc, the warnings came on, after a little drive it seems to have gone back to normal by itself (no longer have a meter to look at, but no warnings), so completely normal behaviour. ive done a lot of short hops lately and still seems to be holding well.

i hope this continues, but i would reccomend anyone thats having the 10% issue where the battery is definetly ok - ie no problems actually starting - to remove the battery monitor from the MMI display in the hidden menu. you may still need to reprogram the battery serial coding with vagcom, to clear the fault and start afresh, but only the once.

Battery problems and jump starts
 

Found this thread when trying to work out why my perfectly working 2006 3.0tdi sport had a suddenly dead battery the other evening. Initially unable to jump start from my wife's S-max so I borrowed some better cables from a mate with a garage and he also gave me a charged heavy duty battery in case. It took both piggy backed to give enough oomph to fire her up and the battery meter was showing only 5%. It was a messy jump start with a lot of arcing due to difficulty attaching the clips in the S-max which partially melted the clip on the negative cable. Lots of strange flashing of lights and MMI action during this. A8 owning mate helping was convinced serious electrical issues at this point. Charge increased to around 60% on the 15 mile run home where I immediately put it on my CTEK charger overnight. It wasn't showing the full green light the next morning but fired up normally so went back to work and checked the meter at lunchtime which showed a reassuring 100%. When I went to the car that evening noticed the alarm led's weren't flashing and battery again dead needing the key in the lock to get in. Luckily this time my friend with 4.0 tdi A8 was around with his and the car fired easily on jumping from his with the thinner cables which were still in the boot. After reading various posts I figured that the 6 year old battery had just suddenly lost ability to hold charge and thanks to the A8 parts team they ordered and fitted a new unit the next day. I was concerned about state of the ECU and there were a few fault codes but these were simply due to the lost battery charge and cleared after which the car has worked fine. At no time did I have any warning lights in dash or messages in MMI. This is a long way of saying that it seems to be possible to get away with messy jump starts without killing battery ECU (I may have been lucky)but definitely advisable to use the earth rod and not the negative terminal of the battery itself. I used to use the CTEK charger on my A6 2.0tdi and it was still on the original battery 9 years later but maybe the CTEK can't do its magic on the A8 when charging through the cigar lighter due to the additional circuitry of the battery ECU preventing the battery conditioning?

D3 3.0 sport 19inch alloys hybrid analogue/digital tv and radio module keyless go and start.

Connect the C-Tek directly to the battery in the boot. It will take a couple of days to fully charge and the green light to come on

So , I now have a new battery, and after 2 weeks the problem returns

Im again getting the 3 minute warning and warning in the dis

What are my options now, is it only down to alternator ( I would have thought that other warnings would appear if this was at fault )

or

the energy management control unit

anything else could cause this?

I think that may just be the D3... mine does it too :)