Given it probably wasn't any newer than the one in there, it's probably for the best in retrospect. One from a much newer car might avoid the risk of hardware/firmware issues, if indeed the existing module is up the creak.

Still puzzling.

After being fine for a few days including overnight last night, I used the car this morning to pop into town and back. Went to go out at lunchtime, central locking dead and battery low again.

Hi Mannyo

Not sure if this is of help but i'm had very much the same problem when i 1st had the car i changed the battrey for a new one which never showed more that 80% on the metter also at the same time noticed that some of the door sensors did not work. over the year the battry would go down to 30% and never got over 60%.To make a long story short it turned out to be one of the door sensor buttons being stuck down and having a drain on the battry . In the end i removed the little button and spring that had become stuck inside the door handle swich. After doing this and replacing the failling battry that i had i have not had a problem over the past 2 months, before this i would find that the car could take the battry down from 100% to 10 in a matter of hours.

I still have the drivers side back door locking button works , which is fine for me. It many be somthing to look into . Now mine is 100% all the time.

I had the same issue with mine when I first got it. Battery would read fine in volts but in reality it was shagged. MMI battery meter all over the shop. I dug out the receipt for the yuasa battery the previous owner had bought in Halfords, took it into them and they tested it and gave me a brand new one.

I updated the MMI to 5570 and didn't bring back the battery meter after it was lost, coded in the new battery and no issues now for 6 months. Car has sat for two weeks and doesn't lose the keyless and started on the first turn.

Heres the thing, mines not had any problems since either. I've not done anything, its just gone away. Because I have the A6 at the moment, I can leave the D3 for days and come back to it and everything is still working as it should.

So still none the wiser, except for the fact the issue is currently not present.