Bad battery, again...
 

So my CEL went on on Sunday, just one day after very long trip (270 miles, last 130 of which were non-stop). The battery was suppose to be charged after that long trip, right??? Well, not so !

It all started with CEL turning on, and some engine sputtering during startup. Sure enough, monday morning 7am I am at my dealer (I just showed up without an appointment)... They hooked it up, and saw a few issues:

a) Bad camshaft position censor (which I guess explains sputtering)
b) "Unfavorable driving condition" - low battery charge. The car starts up fine, but they cant re-charge battery above 40% - it just would not accept charge.

Have to admit, my wife was driving the X for the past 5 weeks, mostly very short trips (1-3 miles each), and weather was cold. So the battery went bad... They swapped the battery, also thinking that low voltage was causing some issues with the camshaft sensor... Apparently sensor was bad too, not sure if the two were related.

My SA made an interesting statement... Apparently with these batteries once they go very low, they will never re-charge to 100%... Dont know if I should buy this BS...

Anyway, this is my 2nd battery replacement...

Sounds like the SA is really trying to help. Not sure about that Battery comment though, I just had a batter down below 10% which went back to a full charge after time on a charger.

Do you lock down your car when it is parked for extended period? Just wondering.

I wonder if they charge it prior to installing it. Batteries should be fully-charged on a battery charger prior to installation to get full capacity, even the newer AGM ones that BMW is using. Many places do not bother, as the charging can be a bit time-consuming and interrupt work flow in the shop.

:iagree:

Yes I ALWAYS lock the car.

I dont know if they fully charged the battery...

Yes, SA is really trying to help, have to give him credit for that.

If you've got a battery charger, put it on it one-time to make sure it gets a full charge.

I can borrow one from my brother... How do I connect it? Can I connect it to the terminal under the hood, or should connect directly to the battery (under the floor of the luggage compartment) ?

With the BMW's electronics, you just never know what you can fry... :)

I believe the owner's manual says to use the terminals under the hood, so that's what I would do.

Terminals under the hood work fine.

Hood, hood??.....I mean bonnet....what happening to me???? I'm turning into an American :-)