Gideon Analytical Labs received two failed RV4141AM ground fault interrupter controllers. The devices had far different impedance values than a new one did on several of the input pins. The RV4141A is a low power controller for AC outlet appliance leakage circuit interrupters. These devices detect hazardous current paths to ground such as an appliance falling into the water. The interrupter then opens the circuit line before a harmful or lethal shock occurs. Internally, the RV4141A has a diode bridge rectiﬁer, Zener shunt regulator, op-amp, current reference, time delay circuit, latch and SCR driver. In addition, an external sense transformer, SCR, relay, two resistors and component selection, unique applications, resigned components, etc.