MizzouTiger

Hello Everyone,

I called our local BMW service center yesterday late afternoon and made arrangements to take it in today. I just got back about an hour ago and am reporting their findings.

They checked the whole electrical system and could not find anything wrong at first. However they started focusing on the battery. They charged and discharged it three times but no issue was observed. On the insistence of the Service manager, the technician tried a 4th time (I think) and the battery failed the test. Their conclusion was that the battery was slowly going bad and although it could still be charged now, it would eventually die. The battery was replaced and all is well now. I tried starting and turning it off 3 times and have not seen the ?message? nor have had to deal with resetting the clock.

Just a side note: Before the battery was replaced, not only the message ?Increased battery discharge!? would appear and the clock would need resetting, the radio which was on, would also be muted. When I mentioned this, the service manager he mentioned that the smarts in the programming of the car would try to shut off all un-necessary functions because there wasn?t enough current to go around. ?

Thank you to all of you for responding.

jawjaboy

My '08 528xi displayed a similar message, in the final analysis my dealer determined that the radio was defective and causing an intermittent high drain on the battery.....even when the car was parked with all systems off. Radio replaced.....all is well, good luck.

planagan

Same problem here. The car was one week in the garage and they determined that it was dua to the bluetooth module. It works fine now. No battery discharge. The bt (pairs to my iphone) works but the iphone (by cable) doesnt. so I guess it is not the bt module but the media module.

paulsp

Just got the message on my F10 after the car sat for 5 months. However it had a high end float charger attached which indicated all was well when disconnected. I'm wondering if the float charge, fancy trickle charger, was not able to keep up with the battery draw while sitting. In any case the car started perfectly and after driving for 20 minutes or so upon restart the message was gone. Nevertheless I'm a little alarmed about the message because the car sits frequently for long periods but always with a float charger.

BimmerFan52

Not sure which charger you have but I recently bought a Deltran Battery Tender Plus and can recommend it highly.

I had to replace the radiator on my wife's SC430 and I had the doors opened occasionally before finally disconnecting the battery. It started fine but I didn't run it long enough to charge it, and several short trips to run errands ran it down enough that it had to be jumped.

The Deltran unit did a great job charging the battery quickly and has four separate computer processor controlled charging stages so it can safely be left to continue charging indefinitely. The 1.25 amp rating should easily keep up with your parasitic drain without the risk of over-charging the battery.

Very reasonably priced at Walmart.
Battery Tender Plus 021-0128 12V Battery Charger - Walmart.com

paul-g

IBS sensor on my was causing that same issue. unplugged it 4 months ago now with no issues. NOW with that said it just proves it was bad and if i was not so cheap i'd replace it for the $275.

so what happens when it goes bad is it starts to check system and keeps turning you computer on and looking for stuff to shut down cause it thinks there is a large draw...the large draw is it's self which it won't shut off lol...that is the simplest explaination of how it works and why.

paulsp

I have two Battery Tender Pluses, for the other cars (VWs) but this one was considerably more expensive and worked fine for 12 years on an A4 then E60, never a problem. Don't know the parasitic draw on the F10 but dealer said the E60 was 50ma, this charger is capable of 150ma so unless the F10 consumes more than 3x the E60 is should have handled it. A 24/7 draw of 150ma would run a battery down pretty quickly and IMO expose these cars to a serious weakness. The charger also indicated the battery was charged when I disconnected it and the Increased Battery Discharge display hasn't reappeared. I've been reading all I can find on the subject, facts are hard to find but several have posted that the dealer blamed the owner for the problem and/or battery failure "because they didn't drive it enough", short trips and/or infrequent trips. This info apparently captured by the car's nanny software and used against the driver. My latest "thinking" is there was nothing wrong with the battery charge but the software nanny saw the car wasn't being driven to its satisfaction and complained, it would have been a valid issue had it not been connected to a charger. Its also my understanding that BMW is now offering a factory installed charger for $500+ with a small external connector. Again no facts yet just speculation but the sophisticated regenerative braking/charging system seems to have created a weakness we never had. And you better drive your car with some frequency and distance or be chastised by first the car then the dealer.

BimmerFan52

Sounds like you need to find out if the car is going to sleep.

The "normal" at rest current draw for the E60 is correctly stated as approximately 50mA, but if the ECM is awake it is substantially more. You would have to measure yours but I would guess that when the ECM is awake current draw easily exceeds 150mA.

Later E60s with comfort access suffered from malfunctioning door handles which would keep the car awake. I don't know much about the F10, but this issue may be a carry-over.

I also have read that the power system will store long term issues of low battery state of charge and net current flow in and out of the battery.

tmoseley

I just starting getting this message after I replaced the battery at Autozone. The old battery had failed one cold morning to start the car after a jump it was fine the next couple days, but with only 600 CCA I didn't trust it. I purchased a battery from Autozone that has 900 CCA and not I get a "increased battery discharge" message. My car is a 2007 525 xi that I bought less than a week ago.

BimmerFan52

If the battery was fully charged at installation and didn't have a bad cell, then either the alternator is not charging the battery or you have a parasitic current draw that is running the battery down each night.

If Autozone didn't test the alternator when the battery was replaced have them do that now. If they did then you need to watch the car (led next to gear shift) which will go off when the car has gone to sleep. If it doesn't go to sleep or wakes up after going to sleep the main computers will awaken and provide a significant current draw on the battery.

If you know how to use a digital multimeter you can measure system voltage while the engine is running to see if the alternator output is good (approximately 14V), and measure the battery voltage after turning the engine off and just before starting it again.