Method for determining at least one internal parameter of an active sensor (1) in a special operating mode, wherein the sensor (1) comprises a sensor element (2), an evaluation circuit (3), at least two connection lines (4, 5), each of which comprises a connection (41, 51) in particular, and a switching module (6), wherein the sensor (1) is switched between a normal operating mode and the special operating mode by way of the switching module (6) and is switched to the special operating mode to determine the at least one internal parameter, wherein the sensor (1) comprises an electrical offset source (7) for at least partially controlling the evaluation circuit (3) in the special operating mode depending on the supply voltage (U-Sup) of the sensor present at the two connection lines (4, 5) such that the at least one internal parameter of the sensor can be determined from the sensor output signal (Out).