2016 M4. Can I save my battery or am I SOL

[ALCOBENDAS]

I put the battery on the ground and connected to another vehicle it already read 14.5v .. after 5 minutes I disconnected it and it read 0v again ... I connected it to an M4 to see if your electronic system did something with the switch .. step the same .. we installed it in a ftype .. it marked 14.5v ... at 20kms the car stopped .. before all the systems were failing ... today I will try to charge it with a new lithium charger ...

[Hoppyumr]

Originally Posted by ALCOBENDAS

I put the battery on the ground and connected to another vehicle it already read 14.5v .. after 5 minutes I disconnected it and it read 0v again ... I connected it to an M4 to see if your electronic system did something with the switch .. step the same .. we installed it in a ftype .. it marked 14.5v ... at 20kms the car stopped .. before all the systems were failing ... today I will try to charge it with a new lithium charger ...

I don't know from experience, but if you have a proper lithium charger that only charges to the correct voltage, you may need to take the battery apart and bypass the contacts that open up on low voltage to charge the battery directly. Again, this isn't from personal experience, so attempt this at your own risk.

Alternatively, I've seen where may be actually two separate companies that have cheaper replacements for our cars. One of them I believe was Antigravity. I'd look into them before I go plopping 2k for a dealer. Either way, I hear they need to be coded to the car.

[Alberta]

Hi guys,

I'm coming from the F90 M5 forum and looking for help.

Did anyone face this issue when plugging-in a CTEK (rebranded BMW) Lithium charger ?

Thanks for your help!

[pgershon]

My battery died recently. I noticed in January when I was planning to have car inspected. It had not been driven for 4 months or so before it died. It took a jump, but BMW said it failed their test and recommended replacing it.

Instead I purchased a CTEK lithium Ion charger and got the battery reading full strength based on CTEK lights. I left CTEK connected. I checked it last 3 weeks or so ago and it still read fully charged. Today I noticed that the CTEK only had one light and it was flashing. I reset the CTEK but it now just gives me a solid green light at the top but all other indicator (I believe 1-7) are off.

Do I have anything else I can do or is my battery dead. If the latter, what is recommended replacement? OEM or another. And neither way, what is best way to procure. Local BMW wants an arm and a leg and my first born...

[BloomRunsDubs]

Originally Posted by pgershon

My battery died recently. I noticed in January when I was planning to have car inspected. It had not been driven for 4 months or so before it died. It took a jump, but BMW said it failed their test and recommended replacing it.

Instead I purchased a CTEK lithium Ion charger and got the battery reading full strength based on CTEK lights. I left CTEK connected. I checked it last 3 weeks or so ago and it still read fully charged. Today I noticed that the CTEK only had one light and it was flashing. I reset the CTEK but it now just gives me a solid green light at the top but all other indicator (I believe 1-7) are off.

Do I have anything else I can do or is my battery dead. If the latter, what is recommended replacement? OEM or another. And neither way, what is best way to procure. Local BMW wants an arm and a leg and my first born...

First off if your car is out of warranty don't ever go to the BMW dealer for anything, don't look at the BMW dealer or even drive near the BMW dealer unless it is to buy a car. Find a good independent shop.

I did end up replacing the battery on that car with a Lifep04 battery, which at the time which ran me about $1000 less than oem. I did a quick google search and it looks like the batteries have gotten a bit cheaper over the years. You most likely have to replace it if the ctek charger is not working.