Freightliner Cascadia 2017–2022 — technical service bulletin
Bulletin SB54-342 · NHTSA communication 10185895 · issued Jan 25, 2021
Technical service bulletin
communication type
Electrical System
component
2017–2022
model years
6
vehicle entries
Official summary
Freightliner Service Bulletin for Rain/Light Sensor Removal. On New Cascadia vehicles, a delay in the timing of communication (hand shake) between the rain/light sensor (RLS) and sSAM generates fault code "33/521940/12 - rain/light sensor - general DTC timeout", which causes the sensor to stop working.
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.