An automobile lighting unit comprising a lighting device provided with one or more OLED light sources, said OLED light source comprises one or more light emitting areas, said OLED light source has a multi-pixel light emitting OLED structure comprising a plurality of said light emitting areas, each of which is associated with a pixel, or a segmented OLED light emitting structure module comprising a plurality of light emitting areas each of which is associated with an OLED segment, electronic means configured to: - control an OLED light source by means of a pilot signal, which has a trailing edge wherein the pilot signal varies between a high value (Vmax) and a low value (Vmin), - determine an electrical quantity indicative of the electrical behaviour of said OLED light source during a measurement time interval (toff) subsequent to said trailing edge of said pilot signal, - determine a failure condition of said OLED light source on the basis of said electrical quantity, wherein said pilot signal comprises a PWM signal, said measurement time interval (toff) following said trailing edge is the OFF time interval of said PWM signal, said electrical quantity comprises the voltage measured across said OLED light source during said OFF time interval (toff) of said PWM signal, said failure condition is indicative of a dead area state in at least one of said light emitting areas, in said dead area state, the OLED light emitting area of the OLED light source remains off, and it does not emit light, even when it is supplied with said pilot signal. a lighting device provided with one or more OLED light sources, said OLED light source comprises one or more light emitting areas, said OLED light source has a multi-pixel light emitting OLED structure comprising a plurality of said light emitting areas, each of which is associated with a pixel, or a segmented OLED light emitting structure module comprising a plurality of light emitting areas each of which is associated with an OLED segment, electronic means configured to: - control an OLED light source by means of a pilot signal, which has a trailing edge wherein the pilot signal varies between a high value (Vmax) and a low value (Vmin), - determine an electrical quantity indicative of the electrical behaviour of said OLED light source during a measurement time interval (toff) subsequent to said trailing edge of said pilot signal, - determine a failure condition of said OLED light source on the basis of said electrical quantity, - control an OLED light source by means of a pilot signal, which has a trailing edge wherein the pilot signal varies between a high value (Vmax) and a low value (Vmin), - determine an electrical quantity indicative of the electrical behaviour of said OLED light source during a measurement time interval (toff) subsequent to said trailing edge of said pilot signal, - determine a failure condition of said OLED light source on the basis of said electrical quantity, said failure condition is indicative of a dead area state in at least one of said light emitting areas, in said dead area state, the OLED light emitting area of the OLED light source remains off, and it does not emit light, even when it is supplied with said pilot signal.