Out of the blue my SWG had no lights/display/nothing. Power is coming into the unit from the main line. It's a 20 yr old system that I replaced a mainboard on about 6 yrs ago and the cell again just this spring. Nothing looked burnt on the board but I ordered a new one and replaced it. No change. Then I thought maybe the display had gone bad and ordered a new one of those. No change. Looking through the Hayward troubleshooting for no lcd/led after checking voltage, fuses and replacing those 2 pieces they assume that the problem is solved. What else could it be?