NHTSA Complaint #11519920 — 2018 FREIGHTLINER CASCADIA

Unsure what system or component failed. Our driver was making a delivery on the morning of 4/29/23. He was parked at the consignee location, engine off, and reported hearing a loud pop sound from the tractor while he was offloading merchandise from the trailer. A fire started under the hood, he attempted to extinguish it with the fire extinguisher and failed. The tractor burned to the ground. If the driver had been in the cab when it started, he could've been killed in the fire. Per online articles I found, it seems there were recalls on this same tractor year/model where fires were involved, but this unit shows no open recalls. Wreckage is available for inspection. CHP came to the seen, but to my knowledge there has been no inspection performed by anyone in any official capacity yet. No warning lamps or messages, or symptoms reported in advance of incident, just the loud pop sound reported by the driver.