This is how to use a K-Line BMW interface to read Bosch ME9.2 (E46 E53).
Reading procedure supported via OBD socket directly or on the bench (direct connect to DME)
Here are the pinout from the ecu ME9.2
You must apply two powers, ground and pin 7 from K-Line interface.
Run software, adjust COM PORT, press Read, and wait for read ISN