What the heck is draining battery current...

[Helmsman]

...while doors are open?

Did som internal detailing today. Spend a couple of hours with the doors on and off open but kept turning of the inside light. Not that the tiny light should drain much current but anyway. When done the car didn't start, was only lucky to have a guy close with starter.

Never had any issues with the battery although it is 4.5 years old. Regular voltage and charge current measuring indicates its ok.

This makes me curious, anyone who have an idea about what is using that much current with the doors open?

Thanks

[M3Bimmer77]

Isn't 4.5 years enough for a battery? Check all parameters. My guess is that the battery might me showing 14.8 volts but it's weak to start the car. Mine was showing 14.8 volts but right after I turned the car off there was a message of "high discharge" then it went to "low battery". Dealer checked it and battery was "old" even though volts were ok. They replaced it and problems are gone for now. Fingers crossed.

[anom3]

Shot in the dark, but in my case battery drain was caused by my EDC module. Theoretically speaking, if the lights turn off, and you are not pressing buttons while cleaning the car, after about 30 minutes, KL30G should kick in and the car should go to sleep.

I ordered a used, but newer one, and it stopped.

Car holds 12.5-12.6 even when left untouched for 3-4 days.

Before, even after a single night I would wake up and it would be at 12.1. Others have reported the same with their EDC modules.

BTW, when I said I ordered a 'newer' one... The hardware version was newer as well as the software. I already upgraded the software on the one I had in there before and it did not help. The newer one was from a LCI vehicle (module produced in 2011+ from what I remember)... My vehicle is 07.07 production.

Worth noting, replacing the module requires that its coded to the car. Does not need to be 'programmed' (eg: flashed with different firmware)... But it does need to be reset to take your E9X M3 paramaters. NCS Expert will do this for you.

I paid about 50 dollars for the used EDC module.

Try pulling the EDC fuse and see if it helps.

[vsix]

Helmsman aren't you charging on regular basis?

It's recommended to do that, at least twice a month.
Bought a few week's a new batt. and will still check now and then it's actual charge condition.

[Helmsman]

Guys, thanks for the inputs. Yes the battery is 4.5 years old but again never seen any fault messages (not even when it refused to start other than "click") and voltage keps around healthy 12.5V+ after several days still.

This time the only difference I can think of is that the doors was closed and opened during a fairly long time. Obviously there are a billion micro's working in the car but can't think of what should cause that extra activity this time?

Anyway let's see if she want to start up again tomorrow.

Cheers

Ps. No unfortunatel I have no possibility to trickle charge as no power outlet available. Was lucky to find a garage down town, guess you can't have it all...

[Move Over]

Originally Posted by Helmsman

Guys, thanks for the inputs. Yes the battery is 4.5 years old but again never seen any fault messages (not even when it refused to start other than "click") and voltage keps around healthy 12.5V+ after several days still.

This time the only difference I can think of is that the doors was closed and opened during a fairly long time. Obviously there are a billion micro's working in the car but can't think of what should cause that extra activity this time?

Anyway let's see if she want to start up again tomorrow.

Cheers

Ps. No unfortunatel I have no possibility to trickle charge as no power outlet available. Was lucky to find a garage down town, guess you can't have it all...

I would look into getting a new battery. That was my indicator that mine was going, kept dying with the doors opening for cleaning and coding.

[Denk]

Parking lights accidentally switched on?

[Rajmun340]

There is a hell of a lot of electronics gadgets and multiple high powered computing modules in cars today, alarm, all kinds of sensors, proximity radar, wireless everything goes through an automatic boot test each time you start the car. Cars are like electronic power hogs now. 4.5 years seems not so early for the battery to go.
Trouble is, there so many electrical stuff in cars now, it increases the likelihood for this kind of issue. Also it's the worst one to diagnose and onboard diagnosis is only good at detecting functionality problem not electrical power integrity.

[Rajmun340]

sorry for hijacking the threat but can anyone tell me what is the correct procedure when manual washing / detailing the car to avoid those unnecessary lights turning on and off from the alarm ?

[hlmiii]

Originally Posted by JoeM3SSII

sorry for hijacking the threat but can anyone tell me what is the correct procedure when manual washing / detailing the car to avoid those unnecessary lights turning on and off from the alarm ?

Leave fob in car when washing.

(If you're concerned about it getting locked in - it's never happened to me in ten+ years - then stick the plastic valet key in your pocket.)

[radiantm3]

Originally Posted by JoeM3SSII

There is a hell of a lot of electronics gadgets and multiple high powered computing modules in cars today, alarm, all kinds of sensors, proximity radar, wireless everything goes through an automatic boot test each time you start the car. Cars are like electronic power hogs now. 4.5 years seems not so early for the battery to go.
Trouble is, there so many electrical stuff in cars now, it increases the likelihood for this kind of issue. Also it's the worst one to diagnose and onboard diagnosis is only good at detecting functionality problem not electrical power integrity.

Yup. I had a draining battery and replaced the battery. Was still draining. Replaced the EDC module (codes said it was faulty). Still draining. The dealership finally narrowed it down to my Lux Angel Eyes which have been fine for 5 years. Went back to the stock bulbs and the problem went away.

[vsix]

Originally Posted by Helmsman

Guys, thanks for the inputs. Yes the battery is 4.5 years old but again never seen any fault messages (not even when it refused to start other than "click") and voltage keps around healthy 12.5V+ after several days still.

This time the only difference I can think of is that the doors was closed and opened during a fairly long time. Obviously there are a billion micro's working in the car but can't think of what should cause that extra activity this time?

Anyway let's see if she want to start up again tomorrow.

Cheers

Ps. No unfortunatel I have no possibility to trickle charge as no power outlet available. Was lucky to find a garage down town, guess you can't have it all...

Oh ok, because now thst I have a new battery, it's not that bad but my old batt. needed full charge every week.
So might be your battery died on you!
After 4 years it's a little to early, so it could be it wasn't properly registered on your first swap?

[Eau Rouge]

@OP: A four and a half year old battery is well past its prime. Even if nothing was amiss, replacing the battery would be on my "do this right away" list. ymmv

Having said that, I too have had the EDC module replaced as it contained an error that reawakened it thirty minutes or so after the car was shut off. The being "awake" state drained the battery which was more than three and a half years old at the time.

So, my suggestion would be...take it to a service center. Ask them to hook it up to a computer overnight so that there's monitoring of the electronics throughout the night. Any issues with EDC or other electronic components will be identified with a review of the activity log on the following day.

[Helmsman]

Originally Posted by radiantm3

Yup. I had a draining battery and replaced the battery. Was still draining. Replaced the EDC module (codes said it was faulty). Still draining. The dealership finally narrowed it down to my Lux Angel Eyes which have been fine for 5 years. Went back to the stock bulbs and the problem went away.

Hmm, interesting input. Actually changed to Lux 160 some time ago. Are you saying they drained when off??

Mean while had no issues since, car starts in a blink, showing good voltage with engine off and well above 14V when on, with reasonable charge current. I'd expect the latter to be crazy high should the battery be completely wasted?

Agree 4.5 years is quite a bit but hate taking her to the dealer before needed...

Thanks for inputs guys.