Mine did that once and was fine the next day. I have 2 model 2009 units and just finished modifying both with Blue LEDs for chlor, and amber LEDs for sleep. At night i sometimes look out the bathroom window on the 2nd floor to see if the unit is working, from the distance I can't see the OEM green LED, and the sleep OEM red LED couldn't be diserned from the red fault lights. Now its easy to tell at any distance. I have pics of the mod and finished results. All pics are 7.1MP (limit hear 256k) so if anyone has an easy idea for sharing with the group I'm all ears.
I never saw bad soldering inside soo i don't know why my OEM green LED failed that one day then came back to life.