AdBlue/SCR faults on a Citroën C4

The owner of this 2016 Citroën C4 contacted the workshop about three months after buying the car. The AdBlue/SCR system had developed faults. The engine control unit had stored errors related to the NOx sensor and the urea temperature signal.

AutoChip read the DCM control unit software and made changes to the SCR/AdBlue control strategy. The video says DPF and EGR operation was intended to be retained, but it does not show the results of a post-programming check.

This case highlights why it is important to identify which system is reporting faults before choosing a course of action. The video provides more detail about the work.