RAM 2500 2019–2021 — technical service bulletin
Bulletin S2121000010 · NHTSA communication 10223298 · issued May 28, 2021
Technical service bulletin
communication type
Back Over Prevention
component
2019–2021
model years
9
vehicle entries
Official summary
Service 4WD Lamp On, 4WD System Does Not Work, 4WD Service Lamp Flashing, Front Axle Disconnect Does Not Engage Or Disengage
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.