RAM 2500 2019–2024 — technical service bulletin
Bulletin 9100508 · NHTSA communication 11016060 · issued Mar 28, 2025
Technical service bulletin
communication type
Unknown OR 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.