BMW i3s 2020 BEV heater issue

[Hammurabi]

Hi all, I have a fault code for the heater, dealer suggested replacing the auxiliary heater to fix the problem. I noticed that my setup has a different flow for the coolant than other cars I’ve seen in online videos or pictures. I have the heat pump option.

As you see in the pictures, my heat pump outflow goes down (A) to a compressor like device to the bottom of the car near the the connection (C) , then goes from (C) back to heater through the pipe shown in (B), etc. the typical cars I have seen don’t have that metal device at the bottom near (C)

I’m thinking of replacing the heater myself but don’t want to cause more problems if this is not a closed system for the heater only. Any idea what the other device near (C)?

Thanks in advance

 

[alohart]

Any idea what the other device near (C)?

The mystery device must be identified in one of the attached files from BMW's I01 Heating and AC Systems Techical Training manual.

 

[Hammurabi]

Thank you very much!q, Yes, I realized after some research it’s actually the heat pump exchange and it’s not connected to high voltage battery.

I managed to replace the heater this weekend, the error code is now gone! I had to follow some important safety steps, and fortunately I didn’t break anything. Now I just need to use the special coolant for i3 heater and fill it with a vacuum machine to avoid any air bubbles.

Finally, my car was not accepting high speed charging (DC), the charging cable won’t lock, even there is nothing wrong with my cable locking mechanism. Deal suggested maybe the heater was causing the charging to fail, since there was a high voltage auxiliary heater error.

I will try DC charging later today and see if the issue is now fixed since there are are no other DTC error codes.

 

[Hammurabi]

Hi All, good news, fixing the auxiliary heater fixed the the DC charging issue too! I was getting error message when charging that cable cannot lock, yet I Knox’s the lock works. The car had 3800 miles on it, and level1,2 charging works. I did have a cable error again this time, but after a second try and pushing the cable, it worked!, before it would not work at all.

Apparently, because the heater had high voltage error, the charging wasn’t resuming, and the charging machine notices the lock disengage, and it stops, as locking is required for safety (making sure you can’t pull the cable quick and cause a spark…)

The error code I was getting is: 801380 which is ‘auxiliary heater high-voltage):fault detecteD.

Bimmerlink could not explain the issue as well as as topdon from topscan using the topguru app, which is dealer quality. I was also able to use functions like turn on the pump, monitor the sensor, etc. I feel bimmerlink was a waste of money, and gimmercode was useful for few modifications to the default settings.

So if any of you have intermittent issues with heater on bmw i3 or i3s , or heater fully stops, it’s likely disabling the DC charging if it is a high voltage error. Even the dealer and BMW who was helping the dealer on the phone was not sure, but made a guess…

I hope that helps in case some of experience the same issue, I couldn’t find any resources that explain the correlation earlier…