[viewdata_revolution]

I have a '17 Xdrive 35i with 16k miles that I bought as CPO. After I kept getting the "Battery Discharging While Stopped" error I took it in to the dealer and was given a new battery. The problem is that the error is still there. It seems to pop up if I don't drive the car for a day or two. I'm in Southern California, so cold is not an issue.

The service rep I talked to when I took the car in said that they need to be driven every three days to keep the battery up, but my dad's new 2019 started without problem or error even after he had been away a month. My X3 lives on the street so a trickle charger would be difficult.

Any ideas of what is going on with this? I've read numerous threads on the "Battery Discharging" error but don't feel like I've got a handle on it.

Thanks!

[Opie55]

Your car is still under factory warranty, let alone CPO. It's nonsense you need a trickle charger for a car you drive every other day or so. Even the dealer said three days. I'd go back and make them figure it out. I have a 6 series with more battery draw than a 3, and it often sits for a few days and I've never had an issue.

[marc x]

Maybe thats why it's a CPO. Its possible the previous owner did something or was having this problem. Dealer has to fix it though and be sure to hold them to it while you have your warranty! After another trip or two to the dealer, contact BMW NA Headquarters.

[Ol' Fart]

This may be a long shot, but have your dealer check both key fobs to make sure none of the buttons are sticking. I know it sounds crazy, but it happened to me. I was getting the battery discharge message and my alarm would sound during the night. Long story short, after several trips to the dealership (45 min. drive) they asked me to bring in both key fobs. Turned out the key fob my wife carried in her purse had a button stick somehow, couldn't tell by looking at it. They replaced the fob and no problems since. Like I said, a long shot, but you never know !

[tracer bullet]

When you drive, how far is it, typically? Road trip, 20 miles to work, 5 miles to work, running multiple errands at places only a mile apart? Do you do the stop / start engine thing allowing it to cut off when you're at a light?

Do you hammer on the accessories - high fan speeds, maybe A/C, heated seats, loud stereo volume?

There's a chance you simply don't drive far enough to make up for the # of times the car has to be started and / or the amount of power you pull. It's a strong as hell alternator but if it doesn't have enough time it might be a problem.

[viewdata_revolution]

That is an interesting idea although the only remedy would seem to be to drive it more often or gimmick up a trickle charger.

I drive the car about 20 minutes every two or three days.

When this started again, though, I got the error even after I'd driven it 40 minutes the previous day.

Thanks!

[oVeRdOsE.]

- dash cam always on?
- something in the 12v+ cig lighter?
- OBDII dongle plugged in?
- aftermarket headunit that keeps the amp always on?
- defect JB piggyback tuner ?
- aftermarket cheap LED that makes a short?

1- do a current drop test (some youtube video show how to find the circuit by checking all fuse. F25 might be very hard according to the location)
2- Or get yourself a current clamp, put it around the 12v from the battery pole, and see if there a reading when door are locked and ing off. I dont know what is the load when the car is stopped, but shouldn't be higher than 1A (12W load)

[kevink1]

I had this issue a few weeks ago. Turned out I forgot I had an OBDII dongle plugged in

I also had it a couple years ago in the winter (even garaged). One time the battery went completely dead (i blame a computer hickup that didn't turn the car accessories off). I've taken to "locking" the car in the garage and that has resolved the occasional issue as long as the OBDII dongle isn't plugged in.

[viewdata_revolution]

It looks like the problem is resolved. BMW said that there was a problem with the Star Link unit in the car that caused it to search for a signal so that it could call home every 15 minutes and update Big Brother with the car's location. They replaced it with a different kind of unit that would not dial home all the time.

It sounded to me as though my car was doing something to make it easy for the repo man to find, but who knows? I'm just happy that the problem was debugged and hopefully solved. In my car owning career I've had plenty of electrical gremlins that were never exorcised.

... after thinking it over.
I think that my CPO was likely a loaner before I got it. When you are given a loaner from this dealership you are told not to take it to Mexico. Part of the explanation I got from the service manager about the frequent GPS pings my car was doing was that it was to make sure the car wasn't taken someplace it wasn't supposed to go. In its previous life, it may have been set to phone home its location to verify that it hadn't gone south of the border.