I've been reading most of the technical threads here in the last month and noted happily that the power failure issues seemed to have passed me over, lucky me.

Halfway a short drive this week, suddenly the flickering iDrive screen, ABS malfunction, Dynamic Drive malfunction, alternator malfunction and finally transmission malfunction. Parked and then nothing...
Upon restarts only the cockpit display came on, displaying the icon for transmission failure.
Then tried to revive it by connecting another car and starter cables, no joy whatsoever. Starter wouldn't even turn. Only clicking sounds from the electrical system.

Finally a tow truck (flatbed->auto tranny) came and with his powerpack it started without a hiccup, no iDrive malfunction messages or anything. Just had to set the time again.
Brought her into a workshop, checked alternator and it was charging and within limits, battery was also OK at that time and IBS didn't seem to act strangely either.
Since then no problems whatsoever (150ish K and 4 days later).

Going to bring her in at the dealer tomorrow, but what should I point them towards?
I reread all the Alternator/IBS threads but could not find decisive symptoms to find the culprit in my case:
- I myself still suspect the Alternator, have seen cases of those getting back within limits for a time.
- Should I get them to replace the battery and reinstall it in the software?
- Or could it simply be the IBS that threw a fit?
Do you have any idea what is to blame, the dealer will probably want to change all three...

Any input from you all is most welcome

Thanks!

By chance had it been recently raining or did you wash your car recently?

Did you check Under your spare tire and batt areas in the back of the car?

Hello BigBadBull,

Thanks for the quick reply!

Forget to mention it: I checked the headliner and trunk under the spare tire well for moisture, hardly any if none...

Will check again to be sure though. On a sidenote: I plan to place a bunch of solid moisture eaters (sp.?) in the electronics bay. That way they would pick up some moisture if needed and if they change color I have a good indication that I need to waterproof my car again. Anyone tried this?

I've put some paper towels around my battery and around the electronics under the spare tyre, in case my sunroof leaks again (it does so only under very heavy rain). I will still have to dry it, but the water won't splash around and damage the electronics.

I also have another idea: to drill a small hole in the bottom of both the battery compartment and spare tyre well. Just to be sure that if water gets in there, it will drain out immediately. I would have to treat the hole in the metal with anti-corrosion, and I would probably also think of some rubber protection from the downside, so that no outside moisture gets in.

Has anyone tried this? Or do you have any ideas why this is a great idea, or a f****ng stupid idea, or any suggestions what to consider when I do it?

My wagon is at the dealer now waiting for parts. Corroded terminals on something under one of the covers in the pAssenger side rear of the car. Dash lit up like a xmas tree a d said heavy current drain. WTF. Have a nice X5 diesel to drive in the meantime.

The Power distribution management controller is located under the spare tire at just about the lowest point of the car. If the Sunroof seal fails or you have a clogged drain guess where the water goes?

There are some TSB's about moving all the Electrical components to higher up , less water prone areas.

X3 and X5's are also prone to the same issue if they have the panoramic sun roof.

Also have they looked at the grounds , if one "broke" loose funny Electrical gremlins tend to crop up.I've never heard of this happening with a E6X but it happens on other cars.

Well in my case there were never any previous anomalies from the electronics except a waterlogged access module last year. Replaced that one and never had problems again.

About a month ago I once got an alternator warning on my iDrive/windscreen that also never came back but that leads me to believe the alternator is at fault?

Also I can't link it to heavy rains or snow, we had quite a lot of both recently and no problems then while she died after a relatively dry period.

Any ideas?

Thanks!

I had the same problems a few weeks ago. I drive dead, nothing worked. Couldn't get my car locked. After 0,5 hour I tried again and everthing worked fine. Al the signals were dissapeard. The only reason I can think of, is that the night before it was freezing -9 C (probably my car couldn't handle the cold ??).

Hello Irshad,

It happened last monday, it wasn't that cold that day compared to the weeks before here as you probably know (had the problem just outside Amsterdam) but maybe it does have something to with it (Battery out of limits due to the cold and IBS cutoff?).
Maybe I'll just wait and see how she behaves the coming week, some freezing expected so...

Thanks!

Well picked my car up yesterday and they had seemingly traced the problem to corroded terminals on one of the 8 pin connectors on the rear power distribution box. Replaced the box but this morning when I started the car it indicated car on lift and high current drain. So here we go back to the dealer. Makes me glad we have 100% free maintenance on these things. But I'm not a happy camper. Electrical issues are always the worst problems to track down. :fcuk::(