We study the existence of weak solutions to a nonlinear strongly coupled parabolic-elliptic PDEs arising in the heating induction-conduction process of steel hardening. In this setting, our major concern is to consider the case when the electric conductivity is nonuniformly elliptic which, together with a right hand side in L 1 in the energy balance equation, yields to a difficult theoretical situation. The existence result gives a weak solution to a similar PDEs system where the energy balance equation has been perturbed by a measure term.' D 0 on 0 .0; T /; @' @n D i !A n on 1 .0; T /; C b.c. on A, (3) M.T. González Montesinos ( )