Technical Service Bulletin 21N06 — 2016 FORD F-250 SD

Certain 2013-2016 Model Year F-Series Super Duty 6.7L Diesel and 2015-2019 Model Year Transit 3.2L Diesel Vehicles Selective Catalyst Reduction System Warranty Extension In all of the affected vehicles, the onboard diagnostic (OBD) system initially contained a software error that prevented illumination of the malfunction indicator light (MIL) if a certain fault was present in the SCR. Since the PCM was reprogrammed under Emissions Recall 21E01, the OBD system is now able to detect this SCR fault previously masked by the software error and can light the MIL if faults are found to be present