[Shovelman]

2017 230 with 45,000 miles, garaged every night. Driven regularly, mostly hiway, so an easy life, especially for the battery.

Now we are going nowhere so it sat in the garage for 10 days. It started fine but the battery nannies popped up. Gave it a good run and all's good now. So my questions are two;

1. Is there any way to tell how low the battery is other than measuring voltage?

2. What is running the battery down?

[overcoil]

I have the same thing going on with my 2015 235 original battery...message about discharging when parked, etcetera.

My is also starting fine, nannies stopped popping up after a long drive during the day yesterday. but I think I was getting warnings last night or this morning again.

[dradernh]

What generally is the expected lifespan of our OEM batteries – anyone know?

[RvR]

Originally Posted by Shovelman

2017 230 with 45,000 miles, garaged every night. Driven regularly, mostly hiway, so an easy life, especially for the battery.

Now we are going nowhere so it sat in the garage for 10 days. It started fine but the battery nannies popped up. Gave it a good run and all's good now. So my questions are two;

1. Is there any way to tell how low the battery is other than measuring voltage?

2. What is running the battery down?

A good shop or even a parts store may have a battery load tester. Voltage alone isn't a definitive test. Have a good test done.

Modern cars have a high parasitic load, too many computers running, even when it's "off," etc. Plus some cars don't charge the battery except when coasting, in an attempt to save a tiny bit of fuel. Some BMW V8s are notorious for eating batteries.

I picked my car up at BMW Welt. When they went through the features in the cabin, my BMW rep asked if she could hook the car up to outside power? I thought this was interesting, with a brand new car, and told her sure. She used the terminals under the hood and the power came from a supply in the turntable. Later, as I was walking around the display floor there was an M4 sitting with a CTek maintainer in the passenger seat. I took a picture of it. It was a 25000 model. I bought the smaller brother (less current, slower charge) for my car:

https://www.amazon.com/CTEK-56-864-A...dp/B006G14FK8/

I don't know the expected lifespan. It'll differ depending on temp and use. I had a friend with an M235i, she lived only 2 miles from work and killed at least two batteries from not driving it enough to have it charge itself. The dealer finally gave her a maintainer and told her to use it. She asked me when to do it? I told her to set a phone reminder to do it once a week for the day she worked from home. No dead batteries after that.

Note that the 4.3 has a "recond" (recondition) mode that the CTeK manual recommends you do once a year. Scott and Shovelman may need to get a maintainer and try a recond and see if it helps. If I'm not going to drive in the next few days, I go ahead and hook the maintainer up, it won't overcharge it and can't hurt. Temperature extremes and discharge are bad for battery lifespans.

[Kemps2Fast]

I had the same issue with my 2017 230i. I park in the garage every night and the car is DD. One night about two weeks ago (car just broke 40k miles) I took the car on a road trip and had parked the car outside. It happened to be a really cold that night and when I had gotten back into the car the next morning, the same thing occurred as you were describing. It freaked me out because I had never had an issue with the car since purchasing it brand new and along with the battery warning, a coolant warning had also come up. Luckily, I was only about 30 miles from a BMW dealership. After speaking to the guys at the dealership, this is a pretty common issue. After about 15 miles of driving and restarting the car, the issue went away and has never occurred again.

[redcars]

I'm surprised that it runs down as big as the battery is. All the cars in the dealer showroom are on battery tenders. Wonder why the Connected app doesn't report low battery.

[dradernh]

Originally Posted by RvR

Note that the 4.3 has a "recond" (recondition) mode that the CTeK manual recommends you do once a year.

Thanks for the heads-up! I've got the same unit and must have skimmed over the explanation of the Recond program. My car spends most of its time on the 4.3, so using Recond will just require one or two presses of the Mode button.

[RvR]

Originally Posted by dradernh

Thanks for the heads-up! I've got the same unit and must have skimmed over the explanation of the Recond program. My car spends most of its time on the 4.3, so using Recond will just require one or two presses of the Mode button.

A couple of weeks ago. The manual says it'll take either a half hour or 4 hours. I didn't watch mine the whole time, but I think it was in-between. Same for my other car I ran recond on.

Once it finished, I switched it back to the normal car icon. I didn't want it going back through recond if we had a power blip, for example.

Recond is stage 6 on the status LEDs, it usually skips over unless you have recond selected.

[MarcoZandrini]

Battery life is dependent upon several factors such as ambient air temps. Cars living in colder climates tend to require a new battery sooner than a car living in a warmer climate. Why? The battery relies upon a chemical reaction to create electrical power. Lower temps slow down that reaction so the battery's actual capacity is lower than that of a car living in San Diego, for example. So, when you cold start the engine in a cooler climate the battery has to "dig deeper" to produce the required energy to crank the engine, run the DME and all the other computers. Basically, the battery "wears out" faster.