Exterior aircraft light unit , comprising: a power input coupleable to an aircraft on-board power supply , at least one LED coupled to the power input for receiving power from the aircraft on-board power supply and configured to emit a light output, an LED circuit board , an end of life detector configured to determine an end of life condition, a fuse circuit coupled to the end of life detector, wherein the at least one LED and the fuse circuit are arranged on the LED circuit board , characterised in that the exterior aircraft light unit further comprises: an optical sensor arranged for sensing a portion of the light output to detect an intensity level of the light output and configured to output a detection signal indicative of the intensity level of the light output, wherein the end of life detector is coupled to the optical sensor for receiving the detection signal and is configured to determine an end of life condition on the basis of the sensed intensity level of the light output; a temperature sensing circuit configured to sense an operating temperature of the at least one LED , wherein the temperature sensing circuit is coupled to the end of life detector , and wherein the end of life detector is configured to determine the end of life condition only if the operating temperature of the at least one LED, sensed by the temperature sensing circuit, is below a normal operation threshold value, wherein the fuse circuit is configured to irreversibly disable power reception at the LED circuit board upon the end of life detector communicating the end of life condition to the fuse circuit. a power input coupleable to an aircraft on-board power supply , at least one LED coupled to the power input for receiving power from the aircraft on-board power supply and configured to emit a light output, an LED circuit board , an end of life detector configured to determine an end of life condition, a fuse circuit coupled to the end of life detector, wherein the at least one LED and the fuse circuit are arranged on the LED circuit board , characterised in that the exterior aircraft light unit further comprises: an optical sensor arranged for sensing a portion of the light output to detect an intensity level of the light output and configured to output a detection signal indicative of the intensity level of the light output, wherein the end of life detector is coupled to the optical sensor for receiving the detection signal and is configured to determine an end of life condition on the basis of the sensed intensity level of the light output; an optical sensor arranged for sensing a portion of the light output to detect an intensity level of the light output and configured to output a detection signal indicative of the intensity level of the light output, wherein the end of life detector is coupled to the optical sensor for receiving the detection signal and is configured to determine an end of life condition on the basis of the sensed intensity level of the light output; a temperature sensing circuit configured to sense an operating temperature of the at least one LED , wherein the temperature sensing circuit is coupled to the end of life detector , and wherein the end of life detector is configured to determine the end of life condition only if the operating temperature of the at least one LED, sensed by the temperature sensing circuit, is below a normal operation threshold value, wherein the fuse circuit is configured to irreversibly disable power reception at the LED circuit board upon the end of life detector communicating the end of life condition to the fuse circuit. <EOS>