A process and an apparatus for locating ground faults in motor armatures includes shorting a commutator of a motor armature with a shorting strap and connecting a variable voltage AC power supply and a load in series between the commutator and a core of the motor armature. The magnitude of a voltage applied by the AC power supply to the commutator is increased until current flows through a winding grounded point on the motor armature. Then a probe of a gauss meter is moved along an edge of the core adjacent the commutator to locate a core slot having a highest magnetic field reading measured by the gauss meter. The probe is moved along the core slot with the highest reading until the gauss meter measures a sudden reduction in the magnetic field indicating the grounded point.
