I have a VZ holden V6 (2007) that has a "Check Powertrain" error coming up. I have google this and it tends to point to an O2 sensor failure.. My scanner shows the O2 for bank 2 is bouncing around so I tend to think that there is a bad sensor. The Lambda for bank 2 is also very different from bank 1. What I would like to be able to see is the actual DTC error codes in the ECM. I have opened up the DTC module but nothing shows in there. I can even clear the error light from my dash but it comes straight back the next time I start the car. I am running the base level V2.4. Is this normal. Does the Scanner actually give the true error codes from the ECM. Any assistance would be appreciated

Keith