My daughter is hoping to pass her test this year and will need a car to get to and from work. My neighbor has just got a new car and has offered my daughter her old KA for £50. Its a 2003 and it has got problems. The engine fault light comes on and I have identified the fault as a P0030 DTC. I am trying to keep the costs down because I think that it is more then likely that the car will have to be scrapped(probably due to rust) which would be a shame. I cant see a lot of rust on it, but the last MOT did give warnings on it. But it would be lovely if my daughter could get a year or two out of it.
So my plan is to see if I can fix the DTC fault or at least see how much it would cost to fix. So I unplugged the pre-cat lamda sensor.
I checked for the resistance between the white wires going to the sensor(which I assume is the heater wires) and I could not get a reading so assuming they are open circuit? So probably the lambda is faulty?
I also checked the voltages on the connector (battery side which connects to the sensor). I am assuming that the grey cable going to the sensor is the ground. And if I connected one side of my meter to that and the other side to the positive terminal on the battery I get 12 volts (what I expected)
I assume that the black cable going to the sensor is the power side, so I connected that to one side of my meter and the other side to the battery ground, but I only got 0.42 volts?
In fact the voltage across the grey and black wires from the car battery is only 0.42 volts. Should'nt this be 12 volts?

I dont know if I should see a voltage across the white wires (battery side), but I did check that and could not read any voltage).

I can for approx £20 get a new lamda sensor from ebay and try it. However when I read a few other posts regarding the replacement of this sensor it looks like there is a TSB from ford that says that the ECU limits need to be updated when a new sensor is installed.

Any ideas how much Ford charge for this? Any other options?

I just need to work out what the cost might be to get the car past an MOT.

Any help appreciated. Thank You.