Freightliner Cascadia 2017–2021 — technical service bulletin
Bulletin P4HalogenEnhance · NHTSA communication 10171977 · issued Mar 3, 2020
Technical service bulletin
communication type
Electrical System
component
2017–2021
model years
5
vehicle entries
Official summary
Customer Maintenance Enhancements for the P4 Halogen Lamp replacement procedure.
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.