Hey folks, I need some diagnostic help. I'm currently getting the 4BCD code related to the DEF system 'Reducing-agent passive-tank fill-level sensor plausibility'. I've read some references that mention the 'processing unit' part number 16197227394' is the culprit when this happens. The DEF tank was replaced under BMW's extended warranty about a year ago. This code isn't new, I've been chasing some others and finally got down to just his one left.
Anyhow, can anyone confirm that this 'processing unit' could be the problem? I searched the forum for a location of the part and the best I can tell is that it is here:
https://photos.app.goo.gl/rRiutX1agE8Zwmzz6
Thanks very much for your help!