Something wrong with my car battery

[ponytuning]

My 2016 x6 50i battery has started to lose charge lately, likely from not being driven that much in the past few weeks and low temperatures in the low 10C but not below freezing (it’s garaged though), so I’ve started to charge it using my trusty charger.
One time I charged it, the voltmeter on the charger read 13v after indicating full charge. Isn’t that unusual considering fully charged batteries should be at 12.6v?
The next time the dreaded battery discharged message came up I charged it again only to find a “bat bat” message on the charger, so something is off, but what?

The car is a CPO and the original battery was replaced at 14800 miles according to the carfax report (it’s sitting at 40200 miles now).

Should I be looking at a new battery?

I should mention that I have a dual dash cam system (not hotwired) that is likely also drawing current after I lock the car for another 15 min or so and The car also came with a stargard gps system installed by the dealer which is also likely to be drawing some power.

LE: after some online reading I learned that the 13.2 voltage comes from the number of cells in my battery times the voltage of each cell, so 6 x 2.2v = 13.2

[CT335xi]

Originally Posted by ponytuning

My 2016 x6 50i battery has started to lose charge lately, likely from not being driven that much in the past few weeks and low temperatures in the low 10C but not below freezing (it’s garaged though), so I’ve started to charge it using my trusty charger.
One time I charged it, the voltmeter on the charger read 13v after indicating full charge. Isn’t that unusual considering fully charged batteries should be at 12.6v?
The next time the dreaded battery discharged message came up I charged it again only to find a “bat bat” message on the charger, so something is off, but what?

The car is a CPO and the original battery was replaced at 14800 miles according to the carfax report (it’s sitting at 40200 miles now).

Should I be looking at a new battery?

I should mention that I have a dual dash cam system (not hotwired) that is likely also drawing current after I lock the car for another 15 min or so and The car also came with a stargard gps system installed by the dealer which is also likely to be drawing some power.

Yeah I hear that the battery on the x5 and x6 have been problems and some were be changed out yearly!! Search I have seen many posting issues . Good luck.

[ComasF15]

There's a bulletin that says the battery may need replacement every two years. The voltage on my X5 is about 12.5 unless charged. An AGM likes to be held around 12.9 V in float. The short story is you likely need a battery. I had mine replaced at Batteries Plus with registration.

[ponytuning]

Thank you both, that’s helpful! Btw, should the aux battery also be replaced?

LE: Found an updated revision of the SIB but it only refers to updating the istep to a newer version which drops the threshold at which the message pops up: https://www.bimmerfest.com/forums/at...3&d=1549200222

[alphaod]

If you don't do a lot of longer trips, the battery will get drained because the fan and water pump to cool the turbos will run after the car is shut off.

Solution is replace the battery often, drive longer distances, or use a tender once a month (I drive a lot and I use a battery tender).

[ponytuning]

My commute is about 60 min / day or 24 miles round trip mostly highway miles. The thing is I only use the car every other day bc my wife and I carpool (we both work for the same employer), so one day we take my x6, the next day her x5. I find myself charging the batteries on both cars at least once per week.
Her x5 is still on the original battery and displaying the same symptoms as mine, so I’m planning on purchasing two new batteries soon.

[jch1511]

If you have any original 4/50k new car warranty left, I would push dealer to replace battery ASAP.

CPO warranty does not cover battery.

[yewlock]

His 4/50k new car warranty most likely over.

[ponytuning]

That is correct, original warranty has lapsed on both cars.

[ComasF15]

I purchased a CTEK charger and our practice is to plug the car in every night. You could charge the one you're not using.... although daily charging is likely overkill. I've been able to double the life of lawnmower size batteries by daily charging.

[scootr]

Ugh - battery problems. This is an unacceptable flaw.
How can it be okay for a new car need a boost charge every week !?
I'm starting to regret buying this car

[-c-]

Originally Posted by scootr

Ugh - battery problems. This is an unacceptable flaw.
How can it be okay for a new car need a boost charge every week !?
I'm starting to regret buying this car

Yea I was concerned also about this issue but the dealer told me the 40e never had those issues because the larger drive battery in the back feeds the smaller AGM batteries and it's always kept full and ready.

Guess I dodged that bullet.

[turboawd]

Originally Posted by ComasF15

I purchased a CTEK charger and our practice is to plug the car in every night. You could charge the one you're not using.... although daily charging is likely overkill. I've been able to double the life of lawnmower size batteries by daily charging.

You shouldn't have to do that. Unless your car sits for a very long time without being driven.

[EdgyE36]

Here's latest SIB on battery replacement: https://f15.bimmerpost.com/forums/sh...1126569&page=3

F15 is off the list for every other oil change replacement. But after much back and forth I got dealer to give me new battery for my recent CPO purchase. I noticed on work order they gave me a 90AH not a 105 but still appreciated it.

[scootr]

Originally Posted by EdgyE36

Here's latest SIB on battery replacement: https://f15.bimmerpost.com/forums/sh...1126569&page=3

F15 is off the list for every other oil change replacement. But after much back and forth I got dealer to give me new battery for my recent CPO purchase. I noticed on work order they gave me a 90AH not a 105 but still appreciated it.

I decoded the vin # and it listed dual batteries for my diesel. The service tech said some of the X cars had an extra Lithium battery assume-ably for the stuff that runs at night?
Anyway it's been very cold here so that knocks a battery down and can make an otherwise marginal (ok) battery fail.

He also warned there are about 15 dis-qualifiers like left lights on etc for the battery warranty... Also he mentioned if the dealer left the car on the lot not started for some time this could void the warranty in which case I would going back to the selling dealer for a replacement (if needed) .
Wish me luck

[ComasF15]

Originally Posted by turboawd

You shouldn't have to do that. Unless your car sits for a very long time without being driven.

What makes me uncomfortable is the voltage I read off the charging post. 12.5V is about 70% state of charge, depending on the the chart you look at. I realize that that is under a constant load. Then there is the SIB about 2 year replacements.

The car is a electrical hog. It's what is takes to do all the cool things it does. If daily charging makes the battery last it's an easy thing to do. I think BMW keeps the charge rate low to help its fuel mileage rating, leaving the owner to deal with batteries.

[scootr]

BMW replaced my battery today on 2018 35d under the original 50/4 yr warranty. I did some voltage checking prior to bringing it in. 12.75v would be fully charged. I did see 15+v running but 12.34 after sitting just 1 hour.

I agree this car must be a juice hog with all the gadgets and gizmos, some of them running all night. I will be keeping an eye on it now.

[ComasF15]

Charge levels of 70% and less hasten sulfation, I found the Battery University pages an interesting read with relevance provided by the luxury German car maker. Of course it could be the other brand....

Follow the other testing links, too.


https://batteryuniversity.com/learn/...es_in_vehicles

[ajob]

The short battery life of our V8 engine cars has one main cause and one simple solution.

The main cause is the repeated battery discharge every time we turn off a hot engine. Due to the overriding need to avoid heat build-up in the "turbo-valley", after stopping a hot engine the main fan keeps blowing some 10-15 minutes using about 10 amps. Doing this twice a day for, say, 300 days in a year adds to about 1000 - 1500 amps/hour yearly battery discharge - that's only to run the fan, add another 500 for all the rest (alarms, dashcams etc.)

A new 100 Ah battery has a service life of some 100 "full discharge cycles" = 10,000 amps/hour (real life estimates vary a lot here), meaning that just the engine stops will kill a battery in less than five to seven years - now add to the above the engine starts and our "dynamic drive" feature, where batteries are charged only when coasting or braking and you will soon get to our far "too short" battery lifes.

Now the solution, whenever possible: everytime you get back home, first thing open the bonnet and connect a charger - must be 8+ amps, such as the larger C-Teks.

In this way most of the amps needed for the cooling fan are supplied by the charger and you gain years in battery life.

[ComasF15]

Another option is to drive gently the last minute or two of driving, about a mile. When parked continue to idle about 2-3 minutes. This will allow turbo temperatures to normalize and heat soaking to disperse through the radiator. Doing this will minimize the time cooling after shut down.

[scootr]

Originally Posted by ComasF15

Another option is to drive gently the last minute or two of driving, about a mile. When parked continue to idle about 2-3 minutes. This will allow turbo temperatures to normalize and heat soaking to disperse through the radiator. Doing this will minimize the time cooling after shut down.

What... Drive gently ?
Are you crazy, man