TSB 23-2161

Some 2018-2021 F-150 vehicles equipped with a 3.0L diesel engine, 2016-2022 F-650/F-750 vehicles equipped with a 6.7L engine, and 2017-2022 F-Super Duty vehicles equipped with a 6.7L engine and built on or before 08-Mar-2022 may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble codes (DTCs) P21DD, P20BA. P20B9, P204C, P208A, P208B, P208C, P203B, P205B, P21CD and/or U02A2 in the powertrain control module (PCM). This may be due to water intrusion within connectors C3613 and/or C4851/C3610 on the reductant harness going to the reductant pump/heater assembly and the reductant level sensor/quality module. This may also be due to movement of the wiring harness causing terminal fretting. To correct the condition, follow the Service Procedure to replace the reductant tank harness, the reductant pump/heater assembly and/or the reductant tank, as well as securing the wiring harness using a cable zip tie fastener.