What about the data bus between the convertible top, the central air/ security module, and the BCM? I have been trying to trace down the convertible top issue with a meter, checking voltages & continuity, from the rear top controller connector. I know the top controller talks to the bcm on a small 3 module network. I see it appears on different pins on the obd connector. My next step was to try & learn & read some bus data to see what I could come up with. Also wondering about what parameters I would need to copy over or change if I replace the bcm with another used one. I'm just getting started w/ my CAN bus (PCAN) tool. Glad to see this new thread!