[fdriller9]

I'll be replacing my battery when I get back to the states. I got a Braille 21lb lightweight battery. It seems this is the time to replace batteries on an '06. I've seen many people on here needing to do it.

Btw, AGM battieres are recommended for short distance driving. 25 minutes isn't that short of a drive so you should be fine.

But I've been getting slow cranks.

[poiney]

Originally Posted by *********

It means the battery has a low voltage reading. If you continue to leave your radio, lights, on etc while the engine is off, you risk draining it to the point where you cannot crank the engine.

So basically it's just warning you that you have just enough juice left in your battery to turn over your engine a few times.

It doesn't necessarily mean that your battery is bad. But draining your battery isn't a god thing either. As your battery drops voltage, the inside will corrode (I think it's corrode)and damage it self, decreasing the ability to hold a full charge.

Yes, but assuming I use the car under regular conditions (i.e., don't leave anything running after the car is turned off and I exit my car) and I see this warning, then it's probably good indication time to get a new one and definitely time to make sure I got jumpers in the car.

The more pressing concern is -- Will the car not start due to a bad battery before the idiot light begins to appear on my dash.

[claykin]

My wife's '08 328 with 34K miles has begun slow cranking. Batt measures 12.2V at rest and 10.1V while cranking. I compared to my 2010 335 and I can tell her battery is on its way out. Took it to dealer and they tell me it passes BMW's battery test. They cannot replace under warranty. Argh!!! I suppose BMW wants customers to wait until its so dead it won't crank the car over. Lovely!

[John 070]

Originally Posted by claykin

My wife's '08 328 with 34K miles has begun slow cranking. Batt measures 12.2V at rest and 10.1V while cranking. I compared to my 2010 335 and I can tell her battery is on its way out. Took it to dealer and they tell me it passes BMW's battery test. They cannot replace under warranty. Argh!!! I suppose BMW wants customers to wait until its so dead it won't crank the car over. Lovely!

It's just a lead acid battery so other than the fact that it costs over $300 to replace at the dealership, I'm beginning to realize that we've made such a big deal about nothing (can you imagine people on a Sonata or Accord forum acting like this over a battery? Of course not, they run over to Sears and get the top of the line for $129 and just put it in and it's done for 4 years). The SA from before XMAS told me BMW rarely (read it as never but this forum says otherwise) replaces a battery under warranty, it's designed to go 5-6 years.

My car has been sitting since the Thu. before the XMAS holiday, no battery tender. Let's see how it does to work today. It's about 30F, not too bad, we'll see.