Fredu

I have one little problem with my car and i hope someone can help me. I put an b18c engine in my eg hach and it work good but have one ecu codes and it make the enginelight turn on. it give code 41 and it should be primary oxygen sensor heater ?. I mesure form ecus pin A6 that it should groud the oxygensensor heating when i turn ignition on? When engine is running it should be from 0-1V but it not. but when i not have ignition on it have 12-14V. The positive side of heating is working like it should. Can it be something wrong with the ecu or something alse?