[493263]

We all know the dreaded problem for city drivers needing new batteries prematurely. I live in DC so it's a problem for me. I tested some behaviors with the car on how to get it to charge if you're in low speed traffic. You can tell when it's charging because the fuel economy bar underneath your tach swings to the blue side. Here's what I found.

Problem: If you drive in normal mode, it rarely charges the battery under 45mph. That's a huge problem as you don't get to go 50+ in the city.

Solution: Use Sport Mode or hold a lower gear longer. Basically, you are engine braking at a higher rpm and forcing it to engage the alternator. You burn more gas but use less brakes.

What I found: It seems like it is based on rpm rather than speed. In normal mode, it doesn't like to go past 2.5k rpm. If you hold a gear higher than that when decelerating(engine braking), it will charge your battery. I took a 2 mpg hit but I've never had to use an external charger anymore. On the highway, whatever mode doesn't matter as the rpm will be high anyways. However, if you are in sport mode, then it just engages the alternator a little quicker(nothing significant).

This has worked for me and kept the battery charge up at optimum level. Even when I left my car in the cold for 3 weeks without driving it, it still cranked up. When the temperature dropped recently to 6F, it still cranked up without a hiccup while every other car in the parking lot had problems.

I did about 4 months of testing with this on the highway and city(I drive mostly city). It was the only way to get the car to charge the battery more often in city driving.

Recommendation: Drive in sport mode in the city. It's fine to use normal or comfort on the highway.

[Bbb34]

Interesting suggestion, I'll give it a try, nothing to lose I guess.

Had a long chat with service manager on this last week as we've had few days of -20 Celsius or below in the city. His response was "well that's normal, these cars are all electronics, and any battery left overnight in this cold will drop down in charge" which, I can "buy" to a certain extent.

He's also suggesting installing trickle charger "we do this with each new car we sell in here in this dealership" and have the car plugged in every time temperatures drop below -10 (which is really 4/5 of the winter days where I live). My understanding is that "charge battery" warning comes on after battery charge drops below 80% on these cars and I can even understand that's the case due to electronics which are sensitive things are setup this way. I also "buy" that because the battery is in the trunk, the engine warmth doesn't protect it as much as it would in any other car during these cold days.

But....

I asked him to consider this explanation from a customer point of view.
You're buying luxury sedan, and having to take these steps to protect the battery seems like a major pain. I also jokingly suggested that this should've been mentioned in either vehicle brochure or manual (not sure that comment was appreciated), and that having to run cables for most of the winter in my driveway is a pain (and never had to be done with any other vehicles I owned in the past). Even if you were willing to live with "low battery" warning, the issue is that the car starts shutting off the features (like fans and heating, kinda important on a cold day - though must admit good thing is that windshield defrost works at least).

Also, I find that on those very cold days, driving the car on the highway for 20-30 minutes doesn't charge enough (does not clear the warning) but the very next day, with temperatures above -15 Celsius, the warning was gone, only to come back the following day, again below -20.

Funny thing is that they kept the car to check the battery and charge it overnight if needed, and gave me a loaner 2014 320xi with 5K km on it. By the time I arrived from dealership to work, parking the loaner and shutting it off gave me "low battery" warning. Also on a very cold day, just to disappear the very next day when the temperatures climbed a bit.

I've read quite a bit on this, and it seems to be "hit and miss" where some owners have this issue and other like me are wondering "can this really be generic BMW issue" that these cars just, to quote my service adviser manager "don't like the cold" ?

[The X Men]

Originally Posted by 493263

You can tell when it's charging because the fuel economy bar underneath your tach swings to the blue side. Here's what I found.

The only time I have seen the blue bar light is when I am coasting. I have not notice the blue bar light up while the car need to charge the battery while it is not coasting.

[Bbb34]

Originally Posted by The X Men

The only time I have seen the blue bar light is when I am coasting. I have not notice the blue bar light up while the car need to charge the battery while it is not coasting.

According to what I know, and I may very well be wrong on this one, that's not the only time your battery is getting charged. That's where it's getting additional charge capturing energy from engine and regular breaking. Otherwise battery gets charged by alternator, just like any other car.

Again, maybe I'm wrong on this one, someone else can correct if I am.

[The X Men]

Originally Posted by Bbb34

According to what I know, and I may very well be wrong on this one, that's not the only time your battery is getting charged. That's where it's getting additional charge capturing energy from engine and regular breaking. Otherwise battery gets charged by alternator, just like any other car.

Again, maybe I'm wrong on this one, someone else can correct if I am.

Yes you are correct, anytime the battery is below 80%, the alternator kicks in even if you are not coasting. I was pointing out that when the alternator kicks in when the battery is below 80%, the blue bar does not light up.

[Grover432]

Originally Posted by 493263

We all know the dreaded problem for city drivers needing new batteries prematurely. I live in DC so it's a problem for me. I tested some behaviors with the car on how to get it to charge if you're in low speed traffic. You can tell when it's charging because the fuel economy bar underneath your tach swings to the blue side. Here's what I found.

Problem: If you drive in normal mode, it rarely charges the battery under 45mph. That's a huge problem as you don't get to go 50+ in the city.

Solution: Use Sport Mode or hold a lower gear longer. Basically, you are engine braking at a higher rpm and forcing it to engage the alternator. You burn more gas but use less brakes.

What I found: It seems like it is based on rpm rather than speed. In normal mode, it doesn't like to go past 2.5k rpm. If you hold a gear higher than that when decelerating(engine braking), it will charge your battery. I took a 2 mpg hit but I've never had to use an external charger anymore. On the highway, whatever mode doesn't matter as the rpm will be high anyways. However, if you are in sport mode, then it just engages the alternator a little quicker(nothing significant).

This has worked for me and kept the battery charge up at optimum level. Even when I left my car in the cold for 3 weeks without driving it, it still cranked up. When the temperature dropped recently to 6F, it still cranked up without a hiccup while every other car in the parking lot had problems.

I did about 4 months of testing with this on the highway and city(I drive mostly city). It was the only way to get the car to charge the battery more often in city driving.

Recommendation: Drive in sport mode in the city. It's fine to use normal or comfort on the highway.

I just plug in my BMW installed trickle charger once a month in the winter. Don't plug it in in the summer. After 14 months, no warning messages yet. Driving in a lower gear just burns more gas so I'm not sure there is much saving there.

[Bbb34]

Originally Posted by Grover432

I just plug in my BMW installed trickle charger once a month in the winter. Don't plug it in in the summer. After 14 months, no warning messages yet. Driving in a lower gear just burns more gas so I'm not sure there is much saving there.

After reading a bit more I decided to listen and am having trickle charger installed in my car. It's not very expensive solution, so I thought I'd give it a try since I really love everything else about the car. Good to read that you had good experience with it. Still I'm not exactly crazy about having to charge it, as this will be the first vehicle I've ever owned that needs to be plugged in regularly.

BTW same service manager mentioned that trickle charger won't really charge the battery as much as keep it on level it currently is at with minimal to no loss of charge in very cold weather.

[The X Men]

Originally Posted by Bbb34

After reading a bit more I decided to listen and am having trickle charger installed in my car. It's not very expensive solution, so I thought I'd give it a try since I really love everything else about the car. Good to read that you had good experience with it. Still I'm not exactly crazy about having to charge it, as this will be the first vehicle I've ever owned that needs to be plugged in regularly.

BTW same service manager mentioned that trickle charger won't really charge the battery as much as keep it on level it currently is at with minimal to no loss of charge in very cold weather.

How old is your battery, if its from 2011, it might be getting weak. Cold weather certainly does not help with the electrical system but I have had temps below zero and have no problem with the battery in my 535i. Trickle charger as the name imply trickle charge your battery when it sense that it is less than 100%. Some chargers will do a quick charge and then automatically convert to the trickle charge mode.

[Bbb34]

Originally Posted by The X Men

How old is your battery, if its from 2011, it might be getting weak. Cold weather certainly does not help with the electrical system....

Right, that's a common sense advice and I'm in 100% in agreement.

I bought the car CPO this summer exactly at 3 year since "in service" date, so I'll assume battery is 3 year old. If I was told battery is old and an issue here, I would have no problem asking them to put a new battery in and move on. He did initially say that battery itself seems to be fine.

The issue I have is getting advice to, in theory, trickle charge even brand new battery every time temperatures are dropping down below -10 because "these cars don't like cold". Friend of mine who purchased brand new X3 from the same dealership was given same advice, gets "low battery" warning now and then and plugs his in from time to time. Winters here are just brutally cold and I get that doesn't help, but again, this is the only car I've ever owned where I'm told to install and use trickle charger regularly. Spoke to few MB and Audi owners I know, thinking that those cars have just as complex electronics, and might be that they are just lucky ones, but no such issue on their cars.

[cdmulders]

Bbb34 - I think we are in the same climate, and my car had the first low battery warning when it was just 3 months old. I'm convinced that my battery is still fine. As was initially proposed, I also occasionally do my commute in sport mode to keep the revs up, and this seems to cure the problem, most of the time. I learned this trick with my previous 5-Series (E39) that also had a habit of running the battery down in Winnipeg. The good news is that even with the low battery warning, my F10 has never failed to start, even when it was -25C.

Cheers.

[Bbb34]

Originally Posted by cdmulders

Bbb34 - I think we are in the same climate, and my car had the first low battery warning when it was just 3 months old. I'm convinced that my battery is still fine. As was initially proposed, I also occasionally do my commute in sport mode to keep the revs up, and this seems to cure the problem, most of the time. I learned this trick with my previous 5-Series (E39) that also had a habit of running the battery down in Winnipeg. The good news is that even with the low battery warning, my F10 has never failed to start, even when it was -25C. Cheers.

Same climate yes, except for the whole east end - west end of the city thing My car also started and worked fine all this time, even those super cold days, except that at one point, fans/heat stoped working. Not sure what would've been next thing system would've turned off to further protect the battery.

Anyway, just got a call from the dealer, car is ready, battery is fine, nothing else (beside the cold) is drawing the power away, and this seems to be just considered "normal" behavior with these cars.

"This is normal" line coming from the dealer is, as understanding as I'm trying to be, what I'm struggling with. Just the fact that I might need to plan to have an outlet handy or be prepared to go for a longer drive to charge the car during multiple day ski trips, visiting family... etc...so I can only hope your advice works. I barely drive in any but sport mode anyway (though have been leaving it in default "normal" mode recently due to slush and snow on the roads).

I'll also give trickle charger a try as well, and see how that goes, but am not exactly thrilled about having to use it.

[Gilgorm]

My battery had the low warning once in the winter of 2012-2013 when the car was about 7 months old. I already own a charger with 2, 15, and 100amp settings so just charged it. I've used it just the once. My 535xi usually only runs for 7-10 kms in the city every other day and hasn't been on a highway for a month. I often use Sport to increase the rpm as others suggested. I doubt you would need to use the trickle charger every day, even when its extra chilly, but it won't charge the battery so you may still want to use a regular charger. The three settings in mine are for trickle, regular and super start. I got it at Canadian Tire.
My F10 lives outside. If your battery is three years old it may just be wearing out.

BTW, my retired E60 had two batteries in 2.5 years and I used the same charger a lot with it. E60s had a lot of battery problems due to the car not going to sleep when it was turned off. Based on forum comments, F10s don't seem to have as many problems in this regard.
Good luck.

[cdmulders]

Originally Posted by Gilgorm

The three settings in mine are for trickle, regular and super start. I got it at Canadian Tire.
Good luck.

I think I have the same charger, and we shop at the same place. Go figure.

-23C / -9F this morning. Dang!

[HighlandPete]

The OP's suggestion of using the transmission to get more revs, simply illustrates that many users are not getting enough battery charge in their normal daily commute.

Let's not forget the electrical demand is very high in winter, so besides the temperature issue we are needing more charge than summer use, just to maintain battery condition.

Look at it this way, there will be thousands of drivers without IBS in their motors (no battery condition warnings) running low battery state/charge, driving around "blissfully ignorant" they are doing so.

HighlandPete

[Bbb34]

Originally Posted by HighlandPete

The OP's suggestion of using the transmission to get more revs, simply illustrates that many users are not getting enough battery charge in their normal daily commute.

Let's not forget the electrical demand is very high in winter, so besides the temperature issue we are needing more charge than summer use, just to maintain battery condition.

Look at it this way, there will be thousands of drivers without IBS in their motors (no battery condition warnings) running low battery state/charge, driving around "blissfully ignorant" they are doing so.

HighlandPete

All great points. I do appreciate the sophistication of this car and the warning, which as you said, many others might not have until it's too late.

But again, as reasonable as (I think) I'm trying to be, not crazy about suggestion to run cables to my car regularly. Talking to those around me with different brands and just as sophisticated electrical system and demands, so far I have not heard them dealing with similar issues, maybe they are lucky, maybe there are differences in electrical power demand, system design, speed of charge, I'm not sure .

This is just one of the threads out there on the topic.
http://www.bimmerfest.com/forums/sho...d.php?t=655109

In order not to hijack the thread, yes, I will try suggested solutions, both, slightly higher revs and trickle charger.

[HighlandPete]

Originally Posted by Bbb34

But again, as reasonable as (I think) I'm trying to be, not crazy about suggestion to run cables to my car regularly. Talking to those around me with different brands and just as sophisticated electrical system and demands, so far I have not heard them dealing with similar issues, maybe they are lucky, maybe there are differences in electrical power demand, system design, speed of charge, I'm not sure .

I wonder what the other manufacturers set their 'low battery' warning threshold at... the differences could be as simple as a lower percentage.

Don't know if that could be a valid reason, as I've not researched it.

HighlandPete

[E90Fleet]

Originally Posted by HighlandPete

I wonder what the other manufacturers set their 'low battery' warning threshold at... the differences could be as simple as a lower percentage.

Don't know if that could be a valid reason, as I've not researched it.

HighlandPete

You must also only compare other makes that have things like electric coolant pumps that run after engine shutdown to cool the turbos.

I know for a fact newer Mercedes and VW here often have low battery problems

[493263]

Hi guys, thanks for suggesting the trickle charger. That's been an old fix but it's very inconvenient. It's not even realistic for most city folks as we don't have a garage.

I don't know if the car charges the battery automatically if power is below 80% or not. That sounds like a really crazy threshold because batteries are considered bad(need replacement) if maximum capacity is only 80% of original capacity. If it does in fact automatically charge the battery if it's below 80%, then why all the dead battery problems? Even I had problems before from city driving.

Here's what I do know. The battery included in our car is made for high discharge and recharge. They also tend to not hold their charge over long periods of time. It's just physics. The higher the charge/discharge rate, the higher the self-discharge rate. So your only solution is to keep it at optimum level.