The linear and nonlinear magnetotransport response of a ballistic semiconductor cross junction with an embedded, symmetry-breaking scatterer is investigated. As a result of the broken symmetry, the so-called ‘bend resistance’ is no longer symmetric in the magnetic field. The experimental curve also exhibits a pronounced peak structure. In the nonlinear transport regime, both the magnitude and the position of the magnetoresistance peaks are drastically influenced by the dc current bias. We also observe new magnetoresistance peaks evolving at high lead currents in some experimental configurations.