[mobitechaz]

The 'activation' procedure that I found on YT did not work. I checked all associated fuses and they were all good. I was able to communicate with the Comfort Access module (CAM) and it appeared to be working well. The door handle sensors all functioned properly when I made contact with the handle. So the issue is clearly not the CAM, even though the functions associated with CAM are all not operative. The issue I believe is with the CAS module (CAS4+) and a permanent internal hardware fault. Whats so odd is that the car will start with the fob at the steering colum, so whatever the problem with the CAS4+ module, it certianly isn't a major problem or the car would not start at all.

As a aside, I have seen situations where the DTC indicated an internal hardware fault, but there was no fault, the issue was with another component that is supposed to send a signal not working, mimicking an internal fault. I've seen that with brake pad depth sensors and trying to clear those codes out of the modules. There is both a scan tool code clearing and the iDrive system fault must be cleared.

An odd thing happened while i was scanning, the TPMS tire pressure module threw a fault, it appeared to have lost communication. hmmm. could they be related? the TPMS also functions off of antennas at the body. I cleared the code and reset the TPMS at the idrive and that resolved that.

Still very stumped on what to check next, other than contact an electronics specialist who fixes CAS units and describing the issue and fault and seeing if its something they have seen before. Hopefully yes, and hopefully not too expensive to fix. Once the CAS module is removed from vehicle for repair, vehicle will be disabled and will not start, so need to find a good electronics repair shop who is reliable. Thanks for reading.