According to some embodiments, a method of determining a resistance of probes on a contactor device is disclosed. The contactor device can include a plurality of probes disposed to contact an electronic device to be tested. The method can include electrically connecting a pair of the probes to each other, and then forcing one of a voltage onto or a current through the pair of the probes. At a location on the contactor device, the other of a voltage across or a current through the pair of the probes can be sensed. A determination relating to a resistance of the probes can be determined from the values of the forced voltage or current and sensed other of the voltage or current.