Webapr 6, 2023 · if no fault comes up, then the problem has been solved. If you see the 520363 fault code along with the spn 3223 fmi 7 code, then that means selective catalyst. Webmar 5, 2021 · when i checked the diagnosis it’s giving me a acm code 3223 and 520363 ats electrical system problem detected. What could be causing it and is it safe to drive. Websep 19, 2019 · in our experience, the following are some of the most common causes of ats failure that we…