METHOD FOR CHECKING THE FUNCTION OF AT LEAST ONE PTC HEATING ELEMENT

摘要

The invention relates to a method for checking the function of at least one PTC heating element (1) which is used in a device (2) for providing a liquid additive (3). The at least one PTC heating element (1) is connected to a voltage source (5) via electric conductors (4). According to the method, a starting current (6) with a first value (7) is provided at a specified operating voltage (8) in a step a). Then, in a step b), a monitoring process is carried out in order to determine whether the starting current (6) with the first value (7) is provided for a minimum duration (9), said minimum duration (9) having a value of at least (5) seconds. The method is used in particular for on-board diagnoses of a device for providing a liquid additive.