Apparatus and systems are disclosed for detecting outages in an LED lamp assembly. An example disclosed lamp assembly includes a plurality of LED circuits serially connected together. The LED circuits include an LED, a first resistor and an optocouper. The example disclosed lamp assembly also includes a sense line electrically coupled to one of the LED circuits. The sense line has a first voltage value when all of LEDs in that plurality of LED circuits are operational and a second voltage value when at least one of the LEDs has failed.