2015 i3 model: 12V starter battery flat

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plugged in , and on the Level 1 charging device, the Charging led doesn't get on. And the charging port on the car, the usual blue light doesn't appear
so we'll see tomorrow am what happens
When the 12V battery's voltage is too low for HV battery charging to proceed, a slow charge of the 12V battery can occur via a dedicated circuit when an EVSE is plugged in. The HV battery pack isn't being charged, so that might be why the charge port LED's don't illuminate.

However, spurious diagnostic trouble codes (DTC's) are likely to have been stored due to the low 12V system voltage. These might need to be cleared with an OBD scanner (e.g., the BimmerLink app communicating via an OBD to WiFi or Bluetooth adapter) before behavior returns to normal. Fortunately, allowing the HV and 12V systems to turn off followed by booting their electronic modules when a door, the frunk, or the hatch is unlocked or opened can clear these DTC's without needing an OBD scanner. Good luck!
 
Unlocked car with fob key
Entered: those warnings i used to have before are not there.
Pressed start button
Panel shows everything at 0

It does ask me to set date and time.

Hv battery 0.0%
Mileage field with how much this hv charge can drive: empty
Mileage driven so far: 0.0 miles

Vehicle info/ onboard computer shows things as blank

After I press Stop, "Low charge . High voltage battery"

What do i do?
 

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Last edited:
Unlocked car with fob key
Entered: those warnings i used to have before are not there.
Pressed start button
Panel shows everything at 0

It does ask me to set date and time.

Hv battery 0.0%
Mileage field with how much this hv charge can drive: empty
Mileage driven so far: 0.0 miles

Vehicle info/ onboard computer shows things as blank

After I press Stop, "Low charge . High voltage battery"

What do i do?
The blanks at the trip computer and having to set date and time is normal after a 12v disconnect. Regarding the low charge, I would recommend trying to charge the car.
 
Ok all looks good now. Mileage reappeared.
How/where do I dispose of the old 12V battery?
Also, can BMW figure out that I have changed the 12V battery myself and give me problems when doing the MOT?
 
Ok all looks good now. Mileage reappeared.
How/where do I dispose of the old 12V battery?
Also, can BMW figure out that I have changed the 12V battery myself and give me problems when doing the MOT?
When I buy a new battery, the retailer charges me extra for not trading in an old battery. The lead is valuable, so don't let anyone charge you to recycle it, they're making money on each one.
 
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