I had the flickering light symptoms. These forums pointed me to the PCB assembly. I thought I would have a look at the old one first before ordering a new one. The new ones are expensive. I found a very obvious loose solder joint on one of the big blue relays. Re-soldered it and all is well. I did not even have to take the board all the way out to do it. Just removed one 1/4" hex head screw, all the connecters to that sub-board, released the four tabs and flipped it over.
Hope this helps
Todd K.