intermittent charging error

[bigmike20vt]

hi.
we have had an i3 for 6 months and for the last month or so we have started getting charging errors.
my zappi tells me the car is full when it isn't OR it says that the EV rejected the charge.

when I unplug I get a flashing red error light on the charge port.
the app is not help it says all good. when I unplug and plug in again it (so far ) works ok.

when charging it charges at full speed - until it stops - it is random when it happens and there is no schedule in the car.

I am hoping it is as simple as a failing 12v battery. car is a 2018 REX with 28kwh usable battery is this likely.? I don't know if it has been changed before.

I don't believe it is my charge point as our other car has no issues.

Please help. sorry for 1st post being a begging one rather in introduction but it is 4:14 am after a failed charge and I just learned I am going away for a week on Saturday leaving my wife with a car she can't rely on. it's me who works around this stuff usually.
thanks.

 

[EvanstonI3]

The 12v battery controls the electronics which in turn controls if the car can charge or not. Normally when the car is charging, the 12v is being charged as well, but it is possible that the 12v is failed to where it will cause errors like this. If the 12v battery is original to the car, it is long past overdue for being changed. You can check to see if the battery is original by opening the Frunk and looking to the left of the Frunk tray for a stamp in the battery case next to the negative terminal of the battery. All you need is a light. See pic for reference on an original 2017:

only original batteries have the "stamp". Replacements would all have a sticker

 

[bigmike20vt]

thanks. I will check when the wife gets home. the car works absolutely fine other than this so I guess if the battery was that goosed I would have other problems too. do you have any other ideas what it could be? it is very odd. the car is working perfectly except for this random (well close to 50% of the time now either prematurely stopping charging or not starting at all.
my wife is bringing home some 100% alcohol as well I will clean the terminals in the car socket just in case.

 

[EvanstonI3]

You should probably try a different ESVE (charger) to see if your "Zappi" is going bad. My first ESVE started randomly not initiating a charge until I unplugged it from the outlet, then plugged it back in. Eventually it just failed entirely.

 

[Dutchi3]

You also may try a different charging cable, unless it is a thethered cable. In EU, we have our own seperate BMW supplied charging cable and it will last on average about 4 years.

 

[bigmike20vt]

I finally got my car to the garage and they tested the battery, and it failed.

so next job is book it in for a new 12v battery.

I hope it sorts it. unlike with an ICE car where you tend to know the battery is on its way out with slow turn over, there is no visible issue with our car. it even just sat untouched for 10 days whilst we were on holiday but it started this morning just fine.

battery test was
Health 36%
180CCA
charge 98%
12.89v
internal R 15.15 mohms
rated 300A.

so another bill to add to the credit card. I just hope i dont put a new battery in and it not make a different to the charging. i did try to look for a date on my battery but could not see one.

 

[wonjuman]

My $0.02: I experienced intermittent charging failures while charging at public chargers a couple of months ago. It happened at multiple charging stations. Then the A/C stopped blowing cold air. My thought was, The heat pump failed. Fortunately, the BMW diagnosis was a failed heat pump controller. Could have been the root cause of both errors. Repair was covered by CPO warranty. 12V battery was also the original 2021 unit and needed replacement. No issues since.

 

[MKSteve]

I finally got my car to the garage and they tested the battery, and it failed.

so next job is book it in for a new 12v battery.

I hope it sorts it. unlike with an ICE car where you tend to know the battery is on its way out with slow turn over, there is no visible issue with our car. it even just sat untouched for 10 days whilst we were on holiday but it started this morning just fine.

battery test was
Health 36%
180CCA
charge 98%
12.89v
internal R 15.15 mohms
rated 300A.

so another bill to add to the credit card. I just hope i dont put a new battery in and it not make a different to the charging. i did try to look for a date on my battery but could not see one.

Would be good to know if changing the 12v battery did resolve the charging issue.