Post Selective Catalyst Reduction Soot Sensor - NAS Only
The post Selective Catalyst Reduction (SCR) soot sensor is located in the exhaust pipe downstream of the SCR catalytic converter. The sensor measures the soot particles in the exhaust gas to evaluate the Diesel Particulate Filter (DPF) functionality.
The soot sensor comprises a sensor element attached to a dedicated control module with a hardwired connection. The sensor and the control module are replaced as an assembly.
The absorbed soot particles form conductive paths between the electrode combs in the sensor element. The control module measures the resistance between the electrode combs. The control module sends a message to the Powertrain Control Module (PCM) via a private Controller Area Network (CAN) bus to evaluate the DPF functionality.
The control module regularly overheats the electrode combs to regenerate the sensor element.