When converting the BMW electrical system to a different speedo, the original charging indicator lamp is usually omitted or replaced by an LED.
In this case, a resistor must be mounted instead of the lamp, otherwise the battery will not be charged.
This plug and play cable set can be used with all SE wiring harnesses as well as with the original wiring harness.
Connection of the SE charging control resistor:
SE wiring harness
If the SE wiring harness is used, the SE charging control resistor is simply plugged into connector 20.
Original BMW wiring harness
When using the original BMW wiring harness, the SE charging control resistor is connected on one side to the blue cable of the plug that goes to the speedometer and on the other side to the switched plus. The switched plus in the case of the original BMW wiring harness is usually green/black.
