{"nhtsa_id":10177693,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2020-07-31","date":"2020-07-30","document_id":"SB54-331","mfr_campaign":null,"replaces":null,"component":"ELECTRICAL SYSTEM; EXTERIOR LIGHTING; VISIBILITY","mfr_system":null,"summary":"Freightliner Service Bulletin for Updated ULB Control Unit for LED Headlamps. New Cascadia vehicles with light emitting diode (LED) headlamps built from January 1, 2017 through February 17, 2020 may experience intermittent disabled headlamps due to an issue with the universal light ballast (ULB). The LED headlamps can turn off if the supply voltage drops below approximately 9V. This low voltage commonly and momentarily occurs when cranking the engine on a vehicle with batteries that are not fully charged. The momentary low voltage may cause the electronic ULB control unit to malfunction. The ULB may not resume normal function until the power supply to the headlamp is disconnected.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2020/MC-10177693-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2020/MC-10177693-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/10177693","components":[{"id":"electrical","name":"Electrical system","parent":null},{"id":"visibility","name":"Glass, wipers and mirrors","parent":null},{"id":"lighting","name":"Lighting","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"FREIGHTLINER","model":"CASCADIA","year_from":2018,"year_to":2021,"match":"exact","vehicle_ids":["2018_freightliner_cascadia","2019_freightliner_cascadia","2020_freightliner_cascadia","2021_freightliner_cascadia"]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}