Head light`s normal and abnormal operation modes detecting method for motor vehicle, involves comparing characteristic of electrical signal with two ranges of values related to mode, and deducing mode from values

摘要

The method involves comparing a characteristic of an electrical signal of an electric line (14) with two ranges of values related to a respective operation mode of an electrical unit, and deducing the mode from the values. The mode is short circuit and open circuit if the characteristic belongs to the range of values defined by values lower than a short-circuit value and values higher than an open circuit value, respectively. An independent claim is also included for a device for detecting two operation modes of an electrical component supplied by an electric line, in a motor vehicle.