SCR CLOSED LOOP CONTROL AT MAXIMUM LIMIT DEF quality low fix on 2017 freightliner DD15 engine

Buying a extra OUTLET Nox sensor (Grey wire) fixed my issue. Additional sensor serves as a bypass sensor.
(NOTE) there were no other known issues with aftertreatment system that contributed to fault alarms. Be sure to check you DEF concentration %.
Sensor cost a little over $500. Worked great for me and hopefully can help you too. I performed a regen after installing bypass sensor. All numbers were in spec.
Highly recommend having DDDL software to properly diagnose issues and check parameters.
This video link listed below helped me initially to troubleshoot my issues but after following steps issue returned quickly which led me to bypassing as mentioned in my video. Check it out for better insight in why you may have similar symptoms.👇🏾👇🏾
• SCR closed loop