Conditions for Setting the DTC

P11CB and P11CC

• The ECM receives a serial data message from the NOx Sensor Module that the NOx concentration disagrees with the calculated NOx concentration for greater than 5 s per drive cycle.

P11D3 and P11D4

• The NOx sensor circuit offset is the amount of NOx that the sensor measures in fresh air and is the zero point for the sensor. This means the diagnostic is enabled during a deceleration fuel cut-off event of sufficient length to remove all the exhaust gas leaving fresh air in the exhaust system. After fresh air is expected, the NOx level is sampled. IF the sample is outside of the expected range, the respective NOx sensor offset fault is stored.
• The ECM receives a serial data message from the NOx Sensor Module that the NOx sensor offset is not within to a calibrated threshold for more than 3 events.