Frank-Li
New member
Last Sunday, I bought my second BMW i3—a 2015 Rex with 72k miles. The price was great because the car had been parked for over three months, causing the 12V battery to die and triggering over 50 error codes.
I also own a 2015 Rex with 130k miles and previously experienced a similar situation when the fuel pump relay failed. In that case, the main battery drained to 0%, which also depleted the 12V battery. My solution was to replace the 12V battery and leave it on a charger until fully charged, which brought everything back to normal.
With this new i3, however, replacing the 12V battery didn’t resolve the issues. The malfunctions still appeared on the screen, and the car wouldn’t take a charge. The charger shows EV connected, the charge port light is solid white, and the instrument panel shows it as plugged in, but the battery level doesn’t change at all.
Here’s what I’ve done so far:
Before purchasing, I saw a post about the car and asked the owner a few questions. He wasn’t very familiar with i3s but mentioned that the car was drivable before he parked it. He had tried to jump-start it with a NOCO jump starter, but that didn’t work.
On Sunday, I brought a new TX24HL battery, replaced the 12V battery, and the car powered on. However, the main battery still showed 0%, and the cooling fan was running at maximum RPM. Since there was no extension cord available to charge it in the parking lot, I decided to take a chance and tow it home, where I could swap parts with my other i3 to troubleshoot further.
Once I got it home, I plugged it into my Level 2 charger and noticed the 12V battery had died again. When I removed the battery, I realized it was already 15 months old, even though it was brand new from Advance Auto Parts. I replaced it on Monday morning with another battery that was only three months old.
I charged this new battery to 13.11V, reinstalled it, and waited for a new Level 1 charger to arrive (I had to return the U-Haul trailer, and the car isn’t drivable, so I couldn’t unload it in my garage).
After about two hours, the new charger arrived, and I saw that the main battery level had risen to 47%, which seemed like a positive development. However, when I plugged in the charger, the same issue persisted: the charger showed EV connected, the charge port light stayed solid white, the instrument panel showed it as plugged in, but the battery level didn’t increase.
I tried clearing the error codes with BimmerLink, but over 40 codes wouldn’t clear. I also used an OBD reader, but the codes returned after clearing. I left it on the charger for 10 hours, but nothing changed.
By the end of the day, I checked the 12V battery again, and it showed 12.06V. I removed it, recharged it to 12.64V, and reinstalled it this morning before leaving. I’m hoping there might be some improvement by the time I get home tonight.
Given this situation, does anyone have any suggestions on what else I could try?
I also own a 2015 Rex with 130k miles and previously experienced a similar situation when the fuel pump relay failed. In that case, the main battery drained to 0%, which also depleted the 12V battery. My solution was to replace the 12V battery and leave it on a charger until fully charged, which brought everything back to normal.
With this new i3, however, replacing the 12V battery didn’t resolve the issues. The malfunctions still appeared on the screen, and the car wouldn’t take a charge. The charger shows EV connected, the charge port light is solid white, and the instrument panel shows it as plugged in, but the battery level doesn’t change at all.
Here’s what I’ve done so far:
Before purchasing, I saw a post about the car and asked the owner a few questions. He wasn’t very familiar with i3s but mentioned that the car was drivable before he parked it. He had tried to jump-start it with a NOCO jump starter, but that didn’t work.
On Sunday, I brought a new TX24HL battery, replaced the 12V battery, and the car powered on. However, the main battery still showed 0%, and the cooling fan was running at maximum RPM. Since there was no extension cord available to charge it in the parking lot, I decided to take a chance and tow it home, where I could swap parts with my other i3 to troubleshoot further.
Once I got it home, I plugged it into my Level 2 charger and noticed the 12V battery had died again. When I removed the battery, I realized it was already 15 months old, even though it was brand new from Advance Auto Parts. I replaced it on Monday morning with another battery that was only three months old.
I charged this new battery to 13.11V, reinstalled it, and waited for a new Level 1 charger to arrive (I had to return the U-Haul trailer, and the car isn’t drivable, so I couldn’t unload it in my garage).
After about two hours, the new charger arrived, and I saw that the main battery level had risen to 47%, which seemed like a positive development. However, when I plugged in the charger, the same issue persisted: the charger showed EV connected, the charge port light stayed solid white, the instrument panel showed it as plugged in, but the battery level didn’t increase.
I tried clearing the error codes with BimmerLink, but over 40 codes wouldn’t clear. I also used an OBD reader, but the codes returned after clearing. I left it on the charger for 10 hours, but nothing changed.
By the end of the day, I checked the 12V battery again, and it showed 12.06V. I removed it, recharged it to 12.64V, and reinstalled it this morning before leaving. I’m hoping there might be some improvement by the time I get home tonight.
Given this situation, does anyone have any suggestions on what else I could try?
