Drivetrain Fault, loud fan and power reduction

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May 31, 2015
I did a diagnostic after a new drivetrain error appeared causing reduced power output. I have errors saying that there is a communication fault with the coolant pump and there's an internal fault in the AC compressor. Some have suggested that I need to replace the coolant pump but I think the problem is potentially more serious requiring the EDME or AC compressor to be replaced. The front fan would run full power constantly while driving or charging and the coolant pump runs constantly even for some time if the car has been locked. I can't add images as there is no way to upload attachments here so can't properly explain the problem until this feature is added.
Hi sdobbie,

Did you solve the problem?
My 2014 i3 has a problem. My front fan is turning with full power and i have a drivetrain error and error code 21E802. Can you please help me out?
Hi sdobbie/hus104

I've also got this problem:

  • Front fan running very fast
  • Drivetrain error, but able to continue with restricted power
  • Error code 21E802 from OBD2 reader

What was the cause of your problems? [I presume you've solved them]
I get this and fix ...check if front white tank is full low more than line ..check coolant line and coolant pump is working ..
Hice un diagnóstico después de que apareció un nuevo error en la transmisión que causaba una reducción de la potencia de salida. Tengo errores que dicen que hay una falla de comunicación con la bomba de refrigerante y que hay una falla interna en el compresor de CA. Algunos han sugerido que necesito reemplazar la bomba de refrigerante, pero creo que el problema es potencialmente más grave y requiere reemplazar el EDME o el compresor de CA. El ventilador delantero funciona a máxima potencia constantemente mientras se conduce o se carga y la bomba de refrigerante funciona constantemente incluso durante algún tiempo si el automóvil ha estado bloqueado. No puedo agregar imágenes porque no hay forma de cargar archivos adjuntos aquí, por lo que no puedo explicar adecuadamente el problema hasta que se agregue esta función.
This is 100% water pump we repair 5 i3 with same problem ... Check the pump is front wheel on driver side... Remove the back plastic on your will see...


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