Electrical funnies?

[Mr Zap]

So my poor old A6 keeps going and I'd find it tricky to function without it, it's just so damned useful! Anyway, the level of electrical "funnies" is steadily increasing ....

I get the low battery one from time to time, that's always cured by pulling the connector off of the MMI unit in the back for a while so it can cold-boot again. Irritating but not time consuming to sort. Other things have started happening though, such as the temperature displayed is clearly wrong, and the clocks between centre display and dash don't agree. However, just once recently I had the all-gears-highlighted problem, i.e. "PRNDS" all in red and it wouldn't start. Corrected itself almost immediately though.

All linked? Does sound to me like a connection problem somewhere....

[Crasher]

How old is the battery?

[Mr Zap]

Oh if only it was that easy! It's only about 2yrs old, and always reads ok on the console battery monitor (unless the MMI has drained it!). Disconnecting (i.e. rebooting) the MMI is a very effective cure for that, works every time, and it is a known, er, feature of it! I do know that the built-in battery monitor is not foolproof but I've found it to be pretty good and I check it religiously.

I'm actually worried about the cabling and connectors in the floor cavities. A couple of years ago the heater matrix sprang a leak and a fair amount of the pink stuff leaked into the cab and under the carpets. I managed to replace it (what a job that was!!) and using various tubes & stuff drain out all the cavities I could get to but I wouldn't be surprised if things aren't happy under there.

[Crasher]

The 4F is horribly prone to water ingress electrical problems, sometimes the e boxes are so full of water I have to use a pella pump to empty them.

[Mr Zap]

E boxes? Sorry, I'm not familiar with that.
Anyway, now we have another "funny", where the auto setting on the light switch has stopped working. It coincided with the near-side sidelight bulb going to heaven - heaven knows how you're supposed to get in there to replace it though! Yes it could be the switch itself, I haven't tested it, but it rarely gets moved and the two manual light settings work fine. So, is there some commonality with these faults, could it be the same control unit or connector block? All fuses, left, right and at the back are fine btw.

[Crasher]

The electronics boxes in the plenum chamber below the windscreen.