TSB 20-2270

Some 2017 F-Super Duty vehicles equipped with a 6.7L diesel engine built on or before 04-Aug-2017 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble code (DTC) P203B. This may be due to a low voltage condition during engine cranking. To correct this condition, reflash the diesel exhaust fluid (DEF) reductant level sensor/quality module using the Urea Sensor Reprogramming tool.