NHTSA Preliminary Evaluation PE21006

In its process for evaluating Early Warning Reporting data, the Office of Defects Investigation (ODI) found twenty-four (24) field reports involving headlight fires on Freightliner Cascadia trucks, model years 2017 and newer produced by the vehicle manufacturer, Daimler Trucks North America (DTNA). ODI contacted DTNA and learned that it was aware of halogen bulb-related thermal events. DTNA stated a belief that the issue was due to incorrect bulb replacement during maintenance. However, some vehicles experienced fires within the original equipment halogen bulb's expected life range.In July 2019, DTNA released a service bulletin and a training video covering proper headlight bulb replacement. There have been 17 fires, with 3 total vehicle losses, since DTNA released this extra training information.On February 25, 2021, ODI opened a Preliminary Evaluation (PE21-006) and sent an Information Request (IR) letter to DTNA.After the PE opening, DTNA reevaluated the data and found additional thermal events at low mileages and decided to file a recall. On May 14, 2021, DTNA submitted recall 21V-357 for 72,508 vehicles covering 2017-2022 models (exceeding the population and model years of this investigation). The planned owner and dealer notification date is July 12, 2021.For the remedy, DTNA will open up the 2-inch access into a 4-inch access hole into the inner fender to provide better access for the maintenance replacement of the bulb, and add a label that provides a visible warning to aid in the correct installation during the change. Additionally, a new foam grommet will replace the flammable rubber boots for both the high and low beam bulbs, improving access to the interface point where the bulbs install into the socket of the reflector. ODI believes that the scope of DTNA recall 21V-357 is sufficient, and accordingly, PE21-006 is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist on other models o