Vehicle
2019 Ford Transit 2.0L Diesel
Title
P22FB00, Replaced NOx Sensor
Complaint
The customer states that the check engine light is on.
Cause
Confirmed the customer’s complaint and found that the check engine light was on. Connected a scan tool and found code P22FB00 – NOx Sensor Performance – Sensing Element Bank 1 Sensor 1. Performed a road test, used the scan tool to monitor live data and found that the NOx sensor signal parameter was erratic. Performed an inspection of the NOx sensor wiring harness and connectors, and found that there were no loose connections or signs of damage. With the key on and engine off, used a multi-meter to check for the presence of voltage and ground at the NOx sensor and found that both were present. Used the multi-meter to check for the presence of a short or open in the NOx sensor wiring harness and found that there were no shorts or opens present. At idle, backprobed the NOx sensor and monitored the sensor signal on a lab scope. The NOx sensor signal, observed on the lab scope, was erratic. These test results verified that the NOx sensor was faulty.
Correction
Replaced the NOx sensor, cleared codes, performed a road test, and verified that the vehicle operated properly. The check engine light did not illuminate and no fault codes returned.