The invention concerns a procedure for the voltage controlled output adjustment of a sensor heater in the exhaust gas system of an internal combustion engine. In order that such a procedure, whereby the operating temperature of the sensor is achieved in the shortest amount of time, can be implemented without the sensor being damaged in the process, provision is made according to the invention, that the heating voltage in a beginning phase of the heat-up phase of the heater is brought to a high value either very quickly in respect to a subsequent phase or precipitously brought to that high value, preferably the operating voltage; and subsequently the heating voltage is continuously or virtually continuously reduced.