hmm there may lie your answer - it might be different for US cars - wasn't aware of this based on my reccomendation, as it was to the OP who is uk based sorry. Someone else should be able to confirm though!
Can confirm mine reads SIM section but won't read CID section and I have been able to clear that fault and I have now diagnosed and solved the issue with a faulty seat occupancy sensor.
That is very strange as the airbag fault code does appear in the SIM section and my C110 has access to it :?
Sorry
I can pretty much confirm its a difference between the US and euro cars. I've tried many tools, none of which work for the 2003 bmw z4 in the US. Only way to do it is INPA or go to indy/dealer and pay up.