Battery Drain Returns out of the blue.

[mannyo]

This evening it appears that after 6 months the battery drain problem occurred again today, I have no idea what the cause is. Last time this happened was January, and it sorted itself out.

Car last driven Saturday, left Sunday. Drove to work this morning with no problem, left work this evening but the car did not start with its usual get up and go. Checked on MMI and saw battery sitting at 60%.

Went on a detour drive to get home, and arrived back with the battery meter on 100%.

Sitting at home this evening noticed the LED in the door had gone out. Went to car, keyless entry dead so unlocked with key remote button. Started fine, checked on MMI again and battery meter now sitting at 10%.

I've just been a 40 minute drive, battery back at 100% again so lets see what happens now. Also went round the whole car and opened and closed the boot and checked everything is closed properly. I'll pop outside soon and see if the car has gone to sleep, really weird.

The car is being taken abroad in a just over 1 week, could really be doing without the hassle at this point. I don't have the tools or even time right now to try and track down a parasitic drain. It will certainly get a good run in that time frame. Dorset > Hertfordshire > Folkstone > Calais > all the way down past Rouen and Caen to the Mt.St.Michel area.

I did do a quick scan with VCDS and the battery manager showed no issues until just before 5am today, and then during this evening it jumped quiet quickly right up to stage 6 at about 8.30pm. Stupidly I cleared the fault codes.

The car is only driven short distances for weeks on end, last time it did any meaningful distance was 150 miles just over a week ago. Since then its covered about 15 miles in 8 days with 2 starts per day except for Sunday when it was left.

Only thing I can think of is the click flap motor is back again, so this evening I once again run the output tests on the HVAC motors. They all seem to work fine except the known stuck one in the engine bay, so I attempted the basic settings which I know fails due to the stuck motor in the engine bay. All now quiet again after the rest of the motors learnt their current values.

Battery is a Varta and now 18 months old and was coded correctly when I changed it.