A sensor control apparatus (100) includes a signal output section (60) which outputs an instruction signal for selecting a drive or protection mode, and a drive circuit (70) which controls the supply of electric current to the sensor. The drive circuit (70) includes detection means (77) for detecting an anomaly of the electrical connection state of the sensor, protection means (81), operable when the anomaly is detected, for forcedly switching to the protection mode, and report means (80) for outputting a report signal after the drive circuit has entered the protection mode. When the report is input, the signal output section outputs an instruction signal for switching the energization mode to the protection mode, and then outputs an instruction signal for switching to the drive mode. When the report signal is again input a predetermined number of times, the signal output section determines that an anomaly has occurred.