Air Flow Meter (AFM) Current Load
BMW used quite some revisions on there ECUs. You might have measured condition 1 with an older or newer ECU. As an example, BMW E30 325i is used with 2 ECU ending on 153 and 173. Maybe the circuit you found doesn't suite one car. Have you tried swapping the ECUs from each to another? Then you at least know if it is ECU related or AFM related.

I would be helpful to mention which car you work on and how high the voltages on the output pin have been.