A telemetry system with a matrixed telemetry switch unit array and a method for determining the switch position of a telemetry switch unit. The switch units include steering diodes and parallel signal paths each with unique resistance values. The signal paths correspond to switch positions and are closed when the switch unit is in the corresponding switch position. A signal source is electrically connected to an input current path and output current path of the array with a corresponding telemetry switch unit coupled into the signal path. A plurality of sensing signals are applied through the array and the resultant signals are measured. The switch position is determined from the resultant signals indicating the resistance value of the switch signal path currently coupled into the array signal path while accounting for the voltage drop of the steering diodes.