P21C4

Reductant Line Heater Relay Control Circuit High

NHTSA 10168471 ↗ NHTSA 10180257 ↗ NHTSA 10221867 ↗

(Diesel Exhaust Fluid) Reductant Line Heater Control Circuit High,

NHTSA 11015599 ↗

RAM

Module, Urea Pump/Level: HD 6.7L (ETL/ETN/ETM) with Mil On P21C4-00 (Reductant Line Heater Relay Control Circuit High / U11C1-00 (Reductant Control Module Received Implausible Data From ECM/PCM), do not replace the DEF Pump. Follow TSB's released and appropriate Service Diagnostics.

RAM

"6 CONTROL UNIT, Diesel Exhaust Customer complaints with malfunction light illuminated on 2019 thru 2024 MY DJ / D2 / DD / DP vehicles with 6.7L (ETL / ETM / ETN) built on or before October 15,2024 and exhibiting DTCs P21C4-00 (Reductant Line Heater Relay Control Circuit High) and / or U11C1-00 (Reductant Control Module received…

RAM

Malfunction Indicator Lamp (MIL) Illumination, Diagnostic Trouble Codes (DTCs) P21C4 – (Diesel Exhaust Fluid) Reductant Line Heater Control Circuit High, and U11C1 – Reductant Control Module Received Implausible Data From ECM/PCM, Set

RAM

"Flash: Diesel Exhaust Fluid (DEF) Dosing Control Unit (DCU) Update Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set the following Diagnostic Trouble Code (DTC): ● P21C4-00 - Reductant Line Heater Relay Control Circuit High. ● U11C1-00 - Reductant Control Module Received …