PROBLEM TO BE SOLVED: To provide a working car such as a combine-harvester having a liquid crystal display part and enabled to investigate a possible cause for an electrical component error.SOLUTION: A combine-harvester 1 comprises: a liquid crystal display part 14； and a display control part 24 for controlling the display of said liquid crystal display part 14. The display control part 24 stores not only the error of an electrical component as an electrical part error history but also the error of a machine body state as machine body state error history, and displays the electrical component error history and the machine body state error history stored, time serially in a one-source display.SELECTED DRAWING: Figure 19
