A pressurized water reactor (PWR) is equipped with a magnetically coupled positioning system known as a control rod drive mechanism (CRDM). In many cases, the plant system that measures the position of the control rods in the reactor core is the digital rod position indication (DRPI) system. The DRPI system is designed to continuously sense and display the positions of each of the control and shutdown rods. Both of these systems consist of coils above the reactor head, connectors at the reactor head and at the containment penetration, instrumentation and power cabinets, and long runs of interconnecting cables in between these system components. The objective of cable testing is to evaluate the condition of the rod control and position indication coils, connections, cables and to identify any defects or anomalies that may adversely affect their normal operation. Various electrical measurements can provide insight into the health and reliability of these rod control and rod position cable circuits. Some measurements are used to identify configuration anomalies, others test the integrity of connectors and proper isolation from station ground, and some validate the health of the coil to identify resistive connections, insulation degradation, or turn-to-turn shorts. This systematic approach to rod control and rod position coil and cable testing increases system reliability, reduces the likelihood of unplanned outages from dropped rods, and reduces outage times and maintenance costs which in turn reduces costs for the electrical utility.