Had a call this morning to my favorite unit. The new ZSM I installed last year, BAYSENS119a, had two error codes. E2 and E4. Searched through paperwork and everything I could find on the net and I just can't seem to find what these two codes are. Any ideas? By the way, I did find a bad UVM module and unit IGV were staying closed. I ordered new board and manually opened vanes 50% to get some airflow. After restart, error codes still there.