Rudy

There is a great document in the technical gallery that explains the entire power system in the E6x. It's pretty much everything you ever wanted to know and more about all this stuff:

https://5series.net/forums/index.php?autoco...i&img=10935

I still think it's important to emphasize that walking up to the car repeatedly (over an extended period of time) and waking it up from sleep mode (for example, to get something out of the trunk or interior) will, without a doubt, eventually cause too much of a collective drain and will trigger the increased discharge warning, etc. If the warning comes up and the car was not repeatedly waken up, then either the battery really is old/bad or there is another module that is either not allowing the car to enter sleep mode or is periodically waking the car up...

fiona

Cheers guys. I understand the tailgate opening is a big issue. However, how lame is that? How am I supposed to pack the car (the big estate I bought to fill with kids stuff) without opening the boot? When I can, I just open the glass but sometimes I need to get into the whole boot space. Would love to see BMW recognise something is wrong with the battery discharge and issue a service bulletin.

Will get the battery checked out but still think my issue is a module not sleeping or waking up.

Just to confirm, Rudy, does walking past the car with the key in my pocket trigger a wake up? I keep my key on my set of keys and do walk past it everyday to get to my other car. You know, the one that actually starts....

Rudy

Although I suspect people will disagree with me, I'm confident that simply walking past a sleeping car with a CA fob in your pocket, etc., will not wake it. As far as packing the car, if you can, just leave the back open. The car will go to sleep and will not wake again as long as you don't open anything else (or close and reopen the back.)

BAK530dat

Hi. I had the same problem until they replaced it with an AGM battery. One year with no problem so far.

rubencr

I've been watching this thread (and others like it) for a couple of years now. My 06 530XiT is on its 3rd battery, about to be transplanted with its 4th. I have experienced many of the dead battery issues described by various forum members including frequent operation of the air suspension compressor, but not including liftgate issues. We'll, the dealer just reported finding what they believe to be the source of the current leak: the fusebox!! After deactivating/disconnecting all possible sources of drain, they were still seeing a current draw. They removed fuses, and still saw the draw! Disconnecting the fusebox solved the issue, so they have agreed to replace the fusebox, along with the battery.

All of this was done at just over 50,000 miles, so I was very nervous about how they would handle it. To the credit of my service writer, they gave consideration to the long-term nature of these problems, and agreed that the problem originated well within the covered term.

Now I have to wait until the part arrives (coming from Germany) and they swap it out to confirm that it resolved the issue.

I don't know if the fusebox will turn out to be the cause of everyone's battery drain problems, but hopefully my experience will help some of you.

Good luck!!

fiona

Didn't get a chance to get it looked at on Monday as auto electrician phoned in sick. Put it on trickle charge at night atm which solves the issues but will book it back in as soon as I can.

Steve J

Fiona's hubby here again.

Something is not shutting down when the car goes to sleep. It's draining 0.8amps which is huge and my trickle charger giving 300ma simply wasn't putting back what was being drained.

Checked the following:

Glovebox light goes out
Interior lights go out
Light by gearstick goes out after a while.
Tailgate light goes out when lock bodged closed (though the light in the button on the electric tailgate doesn't)

Sitting in the car waiting for the AA on Friday, everything went off but after 15 mins the light on the start button came on and something started whirring in the dash (sounded like air distribution vents moving), then went off after 10 mins only to come back on again after another 10 mins.

We don't have comfort access (I know this can cause a similar issue).

IBS is a possibility. How can I check or disconnect it?

Disconnect neg terminal from battery, attach neg from meter to battery neg , positive from meter to neg terminal and measure amps?
pull fuses till amps drop?


Trying to get back into specialist next week for them to look at as I can't use a car which won't last a day parked at work without draining the battery and not starting.

This whole "common" thing is really bad for such an expensive car, especially when dealers want to charge ?120 + vat per hour for diagnostics, and leaving plugged in overnight there they'll charge you 8 hrs labour

Steve J

Pulled the blue connector on the IBS wiring (taped to wiring going to to rear lights) so will see if that makes ay difference.

Had car battery on charge through engine bay connections most of Saturday and most of Sunday, still wouldn't start until I connectd my other car with jump leads.

Can you charge the battery direct in the boot?

JasonH

You can charge the battery directly but you are bypassing the IBS which could get confused - but in your case I'd say that's pretty irrelevant.

Here's something to consider - does you car have a built in Tracker? Is is activated and working properly? I've heard of these going bad so if it's not working it could be your power drain...

Steve J

No tracker as far as I'm aware.
Strange thing was charging from the front points read 3amps going in forthe first hour then it dropped to 0amps (i.e. no charge being accepted by the battery). Left on charge all day but still wouldn't start.

So either the battery is fully charged but something is making it act like it's flat. Or it's flat and won't charge anymore.

Pulling the blue IBS sensor connector did nothing.

In to specialist tomorrow, if I can get it started in the morning by jumping of another car.