(I thought) I completely killed my battery (but was able to restore it!)

[2016M4DVR]

Originally Posted by SD ///M4

That's the same one that I referenced and linked to in my OP.

it sure is but- you did such a good job I didn't even notice it was a link.
Glad it works well for you too.
Wasn't trying to steal your spotlight

[VCO]

The BMW one 61432358315 is worth considering, its made by CTEK for BMW and has the advantage that it also has a lead acid mode so more flexible if you also own other cars / bikes.

[Poiseuille]

Originally Posted by VCO

The BMW one 61432358315 is worth considering, its made by CTEK for BMW and has the advantage that it also has a lead acid mode so more flexible if you also own other cars / bikes.

^^^ this. i have that one, and for those reasons. price with CCA discount was the same as CTEK/Amazon,

[SD ///M4]

As several others mentioned in this thread, the LiFePO4 battery has a battery supervision circuit and a battery isolating switch which isolates the battery if the voltage drops to a specified level, so I didn't completely kill the battery, it just discharged to the point where the battery supervision logic kicked in.

I was looking through the F80/F82 Complete Vehicle Technical Training/Production Information document today and came across the paragraph that describes this, so for future reference, here it is:

"If the voltage falls below 8 V and the battery isolating switch opens, this becomes noticeable by a vehicle electrical system without voltage. Electrical functions are therefore no longer available. In this case the battery should not be replaced straight away as an initial measure. It is generally sufficient to recharge the battery. As soon as the battery supervision circuits detect a voltage over 10 V for longer than 2 seconds, the battery supervision circuits close the battery isolating switch again. The vehicle electrical system is supplied with voltage again. All electrical functions are available again. The battery is then charged again.

The battery only has to be replaced if the battery isolating switch no longer closes or the energy diagnosis specifies a replacement."

This is obviously what happened in my situation. Jumping the battery applied a voltage more than 10V so the supervision circuit closed the battery isolating switch, allowing electrical functions to be available and also allowing the battery to be charged.

[G4BR13L]

Does anyone know when the battery is replaced or when charging if some module needs to be reset? I alwas thought that cars made the last 10 years (?) had some kind of module that monitors the voltage of the battery and that you either have to reset the module of use some kind of tool connected to the OBD port. I could be wrong though.

[figure99]

Originally Posted by G4BR13L

Does anyone know when the battery is replaced or when charging if some module needs to be reset? I alwas thought that cars made the last 10 years (?) had some kind of module that monitors the voltage of the battery and that you either have to reset the module of use some kind of tool connected to the OBD port. I could be wrong though.

Perhaps you are referring to 'battery registration"... yes generally you need to tell the cars computer that the battery has been replaced. I know I did in my 09 E90 via ISTA, but obviously that was an AGM battery. Could have also done it through my Foxwell scanner. The car would still work without registering the new battery, just may not charge it optimally... at least that's how it was with standard AGM battery.

[SD ///M4]

I was notified by another member that there is a reset button on the CTEK Lithium US charger for use with batteries that have an "under voltage protection", like the LiFePO4 batteries found in the M3/M4. For reference, I found this on page 9 of my CTEK manual:

BATTERIES WITH "UNDER VOLTAGE PROTECTION"
Some Lithium-ion batteries have an on-board UVP (under voltage protection) that disconnects the battery to avoid it becoming too deeply discharged. This prohibits the CTEK charger from detecting that there’s a battery connected. To bypass this, the battery charger needs to open the UVP. By pressing the RESET-button for 10 seconds, the charger opens the UVP. During this process, the charging STEP 7 is lit. Once the UVP has been opened and the battery is ready to be charged, the charger automatically starts the charging cycle.

[The English Guy]

I've been procrastinating in getting one of these chargers. This thread has convinced me to get my finger out of my a$$ and do it.
Great info for those M's that hibernate a lot (like mine) or if your unfortunate enough to drain the battery

[dsmclark]

I had the lights on my m3 stay on all night once (I was going to be away so parked it in my parents garage, got out with the engine running to check it was clear from the door then shut it down through the window. then locked it without closing the door and this left the lights on!).

I woke up to an email from the car saying the battery was drained so the car might not start! It also suggested if I didn't need the lights on any more I should maybe turn them off! Car started with out an issue though! 13 hours they were left on. Good job it has LED's all round I guess

[maniz]

Originally Posted by SD ///M4

As several others mentioned in this thread, the LiFePO4 battery has a battery supervision circuit and a battery isolating switch which isolates the battery if the voltage drops to a specified level, so I didn't completely kill the battery, it just discharged to the point where the battery supervision logic kicked in.

I was looking through the F80/F82 Compete Vehicle Technical Training/Production Information document today and came across the paragraph that describes this, so for future reference, here it is:

"If the voltage falls below 8 V and the battery isolating switch opens, this becomes noticeable by a vehicle electrical system without voltage. Electrical functions are therefore no longer available. In this case the battery should not be replaced straight away as an initial measure. It is generally sufficient to recharge the battery. As soon as the battery supervision circuits detect a voltage over 10 V for longer than 2 seconds, the battery supervision circuits close the battery isolating switch again. The vehicle electrical system is supplied with voltage again. All electrical functions are available again. The battery is then charged again.

The battery only has to be replaced if the battery isolating switch no longer closes or the energy diagnosis specifies a replacement."

This is obviously what happened in my situation. Jumping the battery applied a voltage more than 10V so the supervision circuit closed the battery isolating switch, allowing electrical functions to be available and also allowing the battery to be charged.

This was very helpful. Thanks for sharing. Makes sense now how to 'flip the switch' should it happen to somebody else. I would have probably just left a trickle charger on and then been perplexed as to why it didn't charge the battery.

[figure99]

Originally Posted by SD ///M4

I was notified by another member that there is a reset button on the CTEK Lithium US charger for use with batteries that have an "under voltage protection", like the LiFePO4 batteries found in the M3/M4. For reference, I found this on page 9 of my CTEK manual:

BATTERIES WITH "UNDER VOLTAGE PROTECTION"
Some Lithium-ion batteries have an on-board UVP (under voltage protection) that disconnects the battery to avoid it becoming too deeply discharged. This prohibits the CTEK charger from detecting that there's a battery connected. To bypass this, the battery charger needs to open the UVP. By pressing the RESET-button for 10 seconds, the charger opens the UVP. During this process, the charging STEP 7 is lit. Once the UVP has been opened and the battery is ready to be charged, the charger automatically starts the charging cycle.

I'm guessing the charger simply applies a voltage higher than 8v for the ten seconds to open the UVP?

[Br4den]

Originally Posted by SD ///M4

I was notified by another member that there is a reset button on the CTEK Lithium US charger for use with batteries that have an "under voltage protection", like the LiFePO4 batteries found in the M3/M4. For reference, I found this on page 9 of my CTEK manual:

BATTERIES WITH "UNDER VOLTAGE PROTECTION"
Some Lithium-ion batteries have an on-board UVP (under voltage protection) that disconnects the battery to avoid it becoming too deeply discharged. This prohibits the CTEK charger from detecting that there’s a battery connected. To bypass this, the battery charger needs to open the UVP. By pressing the RESET-button for 10 seconds, the charger opens the UVP. During this process, the charging STEP 7 is lit. Once the UVP has been opened and the battery is ready to be charged, the charger automatically starts the charging cycle.

Does anybody know, does the battery have to be in the car and connected when doing this procedure?

[michaelalex17]

I'm more impressed by the fact that you have an M4 and your wife has an M3 haha

[SD ///M4]

Originally Posted by michaelalex17

I'm more impressed by the fact that you have an M4 and your wife has an M3 haha

And we both drive them on the track. Nothing like chasing down your spouse at 140 MPH on the straight in a nearly identical car!

Oh, and we have a 2006 Z4 M Roadster.

[LVI]

Originally Posted by SD ///M4

I understand the difference, but I did effectively kill it for all intents and purposes, as it didn't start the car or even allow the remote to work. I killed it as far as it could be killed before the life saving circuitry kicked in. It was flatlined but performing CPR by jump starting it brought it back to life!

FYI holding the RESET button on the charger for up to 20 seconds would have "woken up" the battery from its dormant state and allowed the charging process to begin. This may need to be done directly to the battery terminals.

[SD ///M4]

Originally Posted by lawrence1

FYI holding the RESET button on the charger for up to 20 seconds would have "woken up" the battery from its dormant state and allowed the charging process to begin. This may need to be done directly to the battery terminals.

Yes, I described this in post #29 in February last year.

[bikenbd22]

What if my car was sitting for 4 months, battery was dead. I jumped the car and started to drive and dash said don't turn car off in yellow, then went red when driving under normal conditions and said Not charging system and I began to spell bad odors of plastic in cabin. I drove home in 5 minutes and turned the car off, it was again dead. I opened the trunk and battery compartment and the smell was definitely coming from the battery! Will I be able to charge the battery???

[petar7408]

Originally Posted by bikenbd22

What if my car was sitting for 4 months, battery was dead. I jumped the car and started to drive and dash said don't turn car off in yellow, then went red when driving under normal conditions and said Not charging system and I began to spell bad odors of plastic in cabin. I drove home in 5 minutes and turned the car off, it was again dead. I opened the trunk and battery compartment and the smell was definitely coming from the battery! Will I be able to charge the battery???

wont hurt to try of course! But at 7 years it might just be time

[paulso]

Has anyone had and been able to get rid of the "Replace battery" message using this battery tender? I came home to a "dead" battery after being away for a couple of months, and although I was able to jump start it, and drive it without a problem for the last month, this message won't go away.

[figure99]

Originally Posted by paulso

Has anyone had and been able to get rid of the "Replace battery" message using this battery tender? I came home to a "dead" battery after being away for a couple of months, and although I was able to jump start it, and drive it without a problem for the last month, this message won't go away.

To my knowledge either the dealer has to do it, or you can do it yourself with ISTA. I did mine myself with ISTA, haven't had an issue since and that was years ago. I also drove it more now and I'm better at connecting the battery tender when I know the car is going to sit longer during the winter months.

[paulso]

Originally Posted by figure99

To my knowledge either the dealer has to do it, or you can do it yourself with ISTA. I did mine myself with ISTA, haven't had an issue since and that was years ago. I also drove it more now and I'm better at connecting the battery tender when I know the car is going to sit longer during the winter months.

I recently just had the car serviced, and the dealer told me I MUST replace the battery and gave me a quote for $1900.

Using bimmerlink I was able to pull the error code, with a message stating that "Error not present currently but stored", so the dealership didn't even attempt to clear de code. Registering a new battery did nothing, but as soon as I deleted the error the warning went away from the center console. I guess time will tell if the dealership was trying to pull a fast one

[figure99]

Originally Posted by paulso

I recently just had the car serviced, and the dealer told me I MUST replace the battery and gave me a quote for $1900.

Using bimmerlink I was able to pull the error code, with a message stating that "Error not present currently but stored", so the dealership didn't even attempt to clear de code. Registering a new battery did nothing, but as soon as I deleted the error the warning went away from the center console. I guess time will tell if the dealership was trying to pull a fast one

Yea my dealer told me the same thing, and quote was over $1800 if I remember correctly. I suspected it was BS, so after a few months I cleared the stored code via ISTA and it hasn't been back since… and it's been over 2 years.