In the affected buses, the positive starter cable may be incorrectly attached to the same Power Distribution Unit stud as the battery cable, exposing the smaller battery cable to a higher current draw during cranking. Exposure to high current draw may cause the battery cable to overheat, melt the wire insulation and increase the risk of a short circuit and a fire.
Blue Bird will notify owners, and dealers will repair the vehicles free of charge. The repair will include: relocating the starter cable from the Electrical Power Stud to the Chassis Power Stud, inspecting the 4 gauge battery cable from Electrical Power Stud to the battery for any damage, and replacing any damaged cable.
Source: NHTSA