[demon]

Looks like I may soon be in the same fix. So far I only get the discharge light when it is cold outside or I am sitting with ignition on and engine not running.
Some thing interesting that no one else has mentioned is the check engine light. Whenever I start in the cold and get the discharge warning I trip a P323f code. It is easy to clear but that is the only time I have seen that code. anyone else seen it?

John

[Hoooper]

Update: I've been using the desulfator for I guess about a month now, maybe more. I plug it in when I get home and unplug in the morning so it runs about 12hrs per day and also ran for a week nonstop over thanksgiving. When I started using it, I could sit in the car with music on for about five minutes before I got the low charge warning. Today I sat in the car for twenty-five minutes with music on before I got the warning. That seems to suggest that it's working nicely.

[dixy2k]

what's a desulfator?

[Hoooper]

Here is an article that talks about it. Honestly the whole category of desulfators seems like nonsense, but sulfation is definitely a real thing and people seem to have had success on various platforms using desulfators so it can't be completely nonsense. I was pretty skeptical about it when I bought mine and I still am, but it does seem to legitimately work. The next test for it will be to try to "save" an optima that wont hold enough charge to lock the doors after driving for a half hour. I'm not holding much hope for that one.

http://batteryuniversity.com/learn/a..._to_prevent_it

[blowinsmoke]

My battery quit at 72000 mi

[demon]

Originally Posted by Hoooper

Update: I've been using the desulfator for I guess about a month now, maybe more. I plug it in when I get home and unplug in the morning so it runs about 12hrs per day and also ran for a week nonstop over thanksgiving. When I started using it, I could sit in the car with music on for about five minutes before I got the low charge warning. Today I sat in the car for twenty-five minutes with music on before I got the warning. That seems to suggest that it's working nicely.

I am going to have to try one of these. I think a lot of the flakey errors on my car are related to the battery getting weak.

Doing some research there are a bunch of different options for a desulfator and the prices range all over the place. I always look at amazon reviews for a clue if a unit is any good - even those reviews are all over the place.
So how did you pick one? do you have a reco?

[Hoooper]

I have some AGM batteries as well as lead avid, so I picked one that is supposed to be compatible with both. I ended up with a batteryminder brand unit

[demon]

OK picked one up off of amazon for about $50. Plugged it in and let it charge for about 5 days. a LOT of the little weird things are gone!

With my key in my pocket the drivers door would not always open - after running the desulfator it now opens every time.

In My Harmon kardon stereo I run USB thumb drives with music, about 50% of the time the play list would start over from the beginning. After running the charger it only happens about 50% when it is cold and the glow plugs kick on.

So far a good suggestion - THANKS

[Hoooper]

Glad to hear. Mine had another week of just sitting and desulfating, seems to be holding up great now. Hopefully this trend continues for both of our sakes. If it adds just a year to the life of the battery (and every other battery I use it on) that would be about the best $50 I ever spend.

[demon]

I have been using it mostly on the D but I have 5 other batteries I plan on running it on. I will probably plug them in one at a time and just let them run as long as I can. Two are boat batteries so they won't be used for the rest of the winter.
Yup if keeps them alive - best $50 auto investment ever.

[dixy2k]

Since we got some warmer weather in SoCal my car does not bother to tell me anything about "low battery charge".
I guess the cold had something to do with an increase drain on the battery. I'm glad I haven't replaced it yet. I drove around with that notification for about two months.

Home Depot apparently has the lowest prices I've seen so far on a 94R battery, just under $150. Walmart would second in line.

[demon]

Originally Posted by dixy2k

Since we got some warmer weather in SoCal my car does not bother to tell me anything about "low battery charge".
I guess the cold had something to do with an increase drain on the battery. I'm glad I haven't replaced it yet. I drove around with that notification for about two months.

Home Depot apparently has the lowest prices I've seen so far on a 94R battery, just under $150. Walmart would second in line.

You might want to try Hoopers suggestion for a desulfator. When it was cold I would regularly get the low battery warning and it would sometime throw a code. I picked one up on amazon for ~ $50 ran it a couple of extended sessions and even in the very cold weather have not seen the low battery.

For $50 it is well worth a try!

[natefank]

I've had the battery discharge light come for like 3 months now, it comes on if I leave the doors open for too long or sit in my car with the radio on. The dealer won't replace it. I just ordered one of the desulfators hooper mentioned, I'll update and let you guys know how it works

[BB_cuda]

Originally Posted by natefank

The dealer won't replace it.

I guess its all in which dealer you use. I only mentioned the low battery discharge message and didn't ask for a new battery. This was during my yearly oil change visit. They offered to change for free. Are you still inside 48 months/4 years?

[Mark M]

The battery in my 2010 335d died the first day I got the car (CPO May of 2013). Dealer replaced it for free.

However, interestingly, the battery in my 2005 X3 is still original. Perhaps newer technology is not always better. Why go through registration if it doesn't equate to longer life for the battery?

[natefank]

I'm outside of the factory warranty, I have 80k miles but have CPO and maintenance package, but the dealership and BMW said its not covered

[natefank]

So I'd like to update everyone on my battery. So I ordered a BatteryMINDer brand charger/desulfator model #1500, so I have had my battery light come on if I have the radio on or doors open for more than like 2 minutes, also my headlights and taillights haven't been coming on when I unlock the door like it used to. Well I got the charger like 2 weeks ago, came with a clamp style hook up, well it didn't seem to be working, I contacted hoooper a few days ago asking how he connected his. His came with o-ring style that he was able to attach to the terminals, so I went to the store and made my own set, ghetto, I know, I have a real set on order. Well I hooked it up on Monday night, Tuesday I kept having the battery light even after driving, I figured I'd give it one more day. I let it charge for 15 hours last night!! This morning, the headlights came on like they used to, and I just sat in my car for over 10 minutes with the raido on and no battery warning came on!!!!
I know this was long but, it worked!! I'll update again in like a week but anyone having battery issues I would highly recommend a desulfator!!

[SSW]

Don't drive the 2008 335i (w/95k miles on it now) very much and have the battery (white) on a Battery Tender almost all of the time, which has been fine until now.

I recently "lost" the clock in my car a couple of times and got a little triangular "!" warning light next to the gear selector in the dash display. But, I was still able to start the car and after I reset the clock the triangular "!" warning light went away.

Assume this means that the battery needs replacement soon but I'm going to buy a desulfator to see if that will eliminate the problem and prolong the life of the battery further.

[Hoooper]

Your battery is already 7-8 years old and has been on a tender. Batteries become sulfated when the voltage is to low which shouldn't be an issue for a good battery on a tender. I think assuming your battery is the original one you might be better off just getting a new one. I am by no means a battery expert though so that's just my $.02

[natefank]

Mine kept having a warning come on the nav screen that said "excessive battery discharge" or something and a battery would show up where the gear selector display is, if that's not coming on I don't think it your battery