RAM 2500 2019–2024 — technical service bulletin
Bulletin 9100508 · NHTSA communication 11016060 · issued Mar 28, 2025
Technical service bulletin
communication type
Unknown / Other
component
2019–2024
model years
24
vehicle entries
Official summary
"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 implausible Data from ECM / PCM). These DTCs will occur after installation of service DCU 68458603AB. Do not replace parts until after the TSB 25-008-24 is performed. If the DTC(s) continue to set, then follow the Service Diagnostics for the applicable DTC."
Vehicles covered
- 2019 RAM 2500
- 2020 RAM 2500
- 2021 RAM 2500
- 2022 RAM 2500
- 2023 RAM 2500
- 2024 RAM 2500
- 2019 RAM 3500
- 2020 RAM 3500
- 2021 RAM 3500
- 2022 RAM 3500
- 2023 RAM 3500
- 2024 RAM 3500
- 2019 RAM 4500
- 2020 RAM 4500
- 2021 RAM 4500
- 2022 RAM 4500
- 2023 RAM 4500
- 2024 RAM 4500
- 2019 RAM 5500
- 2020 RAM 5500
- 2021 RAM 5500
- 2022 RAM 5500
- 2023 RAM 5500
- 2024 RAM 5500
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.