RAM 2500 2019–2021 — technical service bulletin
Bulletin S2008000186 · NHTSA communication 10224048 · issued Nov 20, 2020
Technical service bulletin
communication type
Electrical System
component
2019–2021
model years
12
vehicle entries
Official summary
Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 ? ECU Application Software Code 1 Missing Or Corrupted
Vehicles covered
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.