An electric drive module for a motor vehicle includes an electric motor, a first input member, a first output member and a two-speed module selectively drivingly interconnecting the first input member and the first output member at one of two different drive ratios. The tread blocks include sidewalls limiting the longitudinal groove laterally and projections projecting from the sidewalls into the circumferential groove. The arc detection arrangement is communicatively coupled to the power supply circuit and adapted to assess the severity of arcing in the chamber by comparing the power-related parameter to at least one threshold. A defect on the processed object is detected by a comparison between the first and second differential signals. The two first locating elements and the two second locating elements cooperate to position the locating frame on the PCB.