vash68

I feel like I have read enough threads on battery discharge, including very descriptive and tech docs stuff here:
http://forums.5serie...70#entry1103470

http://forums.5serie...tarted-right-up

However, still need to ask a few questions (below)

I have been having little luck with a battery in my 2009 535xiT, which I purchased used just 6 mo ago. It came with Intersate battery, which drained about every 4 weeks or so.
Interstate dealer found nothing wrong with it and did not replace it under their warranty.

So I purchased a BMW battery AGM type and let bmw dealer happily rip me off by installing and programming it.
3 weeks later I get "High battery drain" on idrive and "Car on a lift" orange light on speedo.

Now, here is the timeline of events preceding the error message:

New BMW battery, AGM type around Thanksgiving (11-25-11) = $450 out of my pocket total.

12-10-11 - short rides in AM for 1 hour, then car unlocked with doors opened for 6 hours while working on RD rewiring and installation (radar is off 99% of time). CA remote out of car range all day (30feet)
Radar detector is disconnected over night

12-11-11 - no driving, another 6 hours with doors opened (radar is off 99% of time), CA remote out of car range all day - at the end of day I get "Car on a lift" sign in speedo, the battery drained to 10% of capacity(per charger) and 11.5V.
Fully recharged it to 100% overnight
Radar detector is disconnected over night

12-12-11 - "Car on a lift" sign during AM start.
Radar detector is OFF over night
12-13-11 - "Car on a lift" sign during AM start AND "High Battery drain" message in iDrive screen while starting engine.



Now my questions:

1. is this normal for a car to drain battery to 10% over ONLY 12 hours of being unlocked and occasionally opening and closing doors?
If so, then how do you guys prevent this while working on your cars?

2. Car on a lift light - what is a meaning of it? Read somewhere that this is maintenance or inspection reminder. My car was serviced at a dealer 2 weeks earlier.. Is it due to "High Battery drain"?

3. Why is "High Battery drain" message only appeared 2 days after the actual battery discharge?

My car has been at a dealer twice before for "Increased battery discharge" message, they found nothing, replaced CA remote battery and sold me a new car battery

4. is "Increased battery discharge" the same as "High Battery drain"?
I never saw "High Battery drain" before today...



Since 12-12-11 AM I had my Radar detector has been connected to an unused fuse socket #42 behind glove box, which is used by a CD changer, which I do not have.

What I noticed is that RD would not power off till about 5 minutes after the car is locked.
So I had to power it off manually before locking the car (just in case)
5. Could that have contributed to the car not going into a sleep mode and why?

I read here that some circuits disconnect ground instead of positive wire, like in normal cars
How to connect aftermarket accessories to BMW
After testing around cockpit of my car, I could not confirm this about auxillary power sockets or cigar lighters, but the positive bus in fuse box behind a glove box def stays ON after ignition was switched OFF, so maybe there are some modules that use switched ground as opposed to switched positive and for that reason I should not be connecting my RD DIRECTLY to that fuse box positive bus. Need to use ground switched relay instead?
I see myself reconnecting RD to a hard-switched circuit, like cigarette lighter, so I can sleep better at night.. Any better ideas on powering RD would be appreciated

6. Could anybody confirm the way aftermarket accessories should be wired in these cars?

7. Does any one know how much current this car draws when it wakes up?


What a royal pain...

Gilgorm

Are you still under original warranty? If so, the dealer should be checking every module in your car to verify it is going to sleep correctly. My Comfort Access main module was replaced due to High Battery Drain as well as my electronic gear shifter and finally an aftermarket Boomerang system (Lo-Jac) was removed. These three items were causing the problems. There are lots of modules on these cars as well as items that don't turn off properly (fuel pumps, CD changers, Nav systems etc. Your RD could be causing the problem as well.

Also, my battery was replaced free of charge by my dealer in the last week of my 4 year warranty due to it not testing well.
Maybe things are different in the US but I think the dealer ripped you off (if the car is still under warranty-otherwise disregard).
Good luck with your search for the culprit. Mine took three visits over a three week period.

vkhong

When I work on my E90 and E60 for extended periods of time, I put a smart charger on the jump start connections under the hood, and run the charger at 6A. Works well for me.

If airbags are to be disconnected, I disconnect the ground terminal on the battery in the trunk.

I believe the vehicle should go to sleep 20 minutes after engine shut-off and door closure. The light for the door lock switch should go off (and auto transmission shifter, window lockout indicator, auto-dimming mirror, etc). Either an accessory or control module is not allowing your vehicle to go to sleep,

For my RD, I use the 12VDC socket under the glovebox, with wire routed, out of view, to the headliner.

turbo_lew

it sound like something is not sleeping, this happened to me. i had unpluged the radio without disconnecting the battery which shorted a module and cause the battery discharge issue.
If you still have bmw warranty remove any accessories you may have hard wired and book it in. if you leave anything wired in they may try to blame you for the fault and not pay.
good luck anyway.

sahiljain22

Please double/triple check anything aftermarket that you might have installed.

And take them out before going to the dealer. They will blame it, even if its is just hanging there and not plugged in.