Impurity-induced absorption of light in quantum wires in the presence of external collinear electric and magnetic fields directed perpendicular to the nanowire axis is studied theoretically. The dopants in the quantum wire are modeled by a zero-radius potential. Expressions governing the light absorption coefficient are derived, and specificities of impurity light absorption are studied for all possible directions of polarization of the light wave. In particular, some of optical transitions that are forbidden in the absence of fields become allowed in the presence of external fields. Frequency dependences of light-absorption coefficient, along with the influence of electric and magnetic fields on the magnitude of absorption induced by impurities, are investigated. The possibility of controlling optical characteristics of nanowires by means of an electric field is demonstrated.