1999 Freightliner Fl50 Fuse Box Diagram ((top))

Why? Because Freightliner, like many heavy-duty truck manufacturers, did not use a one-size-fits-all electrical system. The FL50—a popular medium-duty truck often used for dump trucks, tow trucks, and box vans—could be equipped with various cab configurations (like the Business Class or the FL-series cab) and different engine/harness packages.